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CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Application No. 60/436,888, filed Dec. 27, 2002.
BACKGROUND OF THE INVENTION
The present invention relates to a heat activated epoxy adhesive and its use in a foam insert that is bonded to a metal body. Structural foam inserts (SFIs) have been developed to reinforce structures within motor vehicles to add strength and stiffness to the vehicle at the site of insertion. Acoustical foam inserts (AFI) have been developed to reduce the impact of noise and vibration on vehicle passages. For example, an SFI coated with an uncured expandable epoxy adhesive is secured to the B-pillar cavity of an automobile. An AFI is typically placed in a hollow part of an automobile for the purpose of preventing the transmission of noise and vibration throughout the hollow cavity. AFI may comprise a foam coated with an expandable adhesive. The automobile body is then subjected to electrodeposition coating (e-coating) and bake, whereupon the epoxy adhesive expands through heat activation to form a bond between the foam insert and the sheet metal. However, one problem associated with expandable adhesives of the prior art is their propensity to crosslink before they expand. This premature crosslinking results in ineffective wet-out of the vehicular substrate and concomitant weaker bonding. Furthermore, solving the problem of premature crosslinking—for example, by reducing or eliminating catalyst—creates another problem, namely, the formation of a cured expanded polymer with acceptable adhesion at the expense of large voids (number weighted mean diameter of >2000 μm), the formation of which decreases durability and results in reduction in mechanical properties.
It would therefore be an advance in the art of foam inserts to provide an expandable adhesive for the insert that efficiently wets out a substrate before crosslinking occurs, thereby creating optimal chemical bonding and enhanced durability, but which produces small voids, thereby resulting in enhanced mechanical properties.
The adhesive of the present invention can expand up to 350 percent. To insure the cavity is filled, expansion is limited by the available space in the cavity. The adhesive present invention creates an equalizing pressure which helps align the part in the cavity.
SUMMARY OF THE INVENTION
The present invention addresses a need in the art by providing an expandable adhesive comprising a) a cured 1-part epoxy resin; b) a viscosity increasing agent; and c) not greater than 25 parts by weight of an inorganic filler, based on 100 parts of the epoxy resin, wherein the adhesive when expanded contains voids having a number average or weighted mean diameter of less than 1000 μm.
In a second aspect, the invention is a structural foam insert comprising a) an expanded polymer, and b) an expandable adhesive contacting the expanded polymer, which expandable adhesive contains i) a 1-part epoxy resin; ii) a polymeric viscosity enhancing agent; iii) a blowing agent; iv) a catalyst; and v) a curing agent, wherein the expandable adhesive has a Young's modulus of at least 500 mPa at 100% expansion, preferably 600 mPa at 150 percent expansion.
In a third aspect, the present invention is a reinforced vehicular frame comprising a) an expanded polymer, and b) an expanded adhesive bonding the expanded polymer and the vehicular frame, which expanded adhesive contains i) 1-part cured epoxy resin; and ii) a polymeric viscosity enhancing agent; wherein the expanded adhesive has a Young's modulus of at least 500 MPa at 100% expansion.
In a fourth aspect, the present invention is a method of preparing foam insert comprising the steps of 1) contacting an expandable adhesive with an expanded polymer under conditions sufficient to gel the expandable adhesive without crosslinking; b) placing the expanded polymer with the gelled expandable adhesive within a vehicular frame; c) heat activating the expandable adhesive to create a expanded adhesive that forms a bond between the expanded polymer and the vehicular frame; d) curing the expanded adhesive; wherein the expandable adhesive contains i) a 1-part epoxy resin; ii) a polymeric viscosity enhancing agent; iii) a blowing agent; iv) a catalyst; and v) a curing agent, and wherein the expanded adhesive contains voids having a number weighted mean diameter of <1000 μm.
In a fifth aspect, the present invention is an expanded adhesive comprising a) a cured 1-part epoxy resin; b) a viscosity increasing agent; and c) not greater than 25 parts by weight of an inorganic filler, based on 100 parts of the epoxy resin, wherein the expanded adhesive contains voids having a number weighted mean diameter of <1000 μm.
The present invention addresses a problem in the art by providing an foam insert with an adhesive that efficiently wets out a substrate before crosslinking occurs, thereby creating superior chemical bonding and enhanced durability, but which produces reduced cell structure, thereby resulting in enhanced mechanical properties. The adhesive of the present invention can expand up to 350 percent. To insure the cavity is filled, expansion is limited by the available space in the cavity. The adhesiveof the present invention creates an equalizing pressure which helps align the part in the cavity.
DETAILED DESCRIPTION OF THE INVENTION
The expanded polymer (also known as a rigid foam) used to make the foam insert has a Young's modulus of preferably at least 200 MPa, more preferably at least 350 MPa; a T g of preferably at least 50° C. and more preferably at least 80° C. and a density of less 1 g/cm 3 , more preferably less than 0.7 g/cm 3 and preferably at least 0.0016 g/cm 3 and more preferably at least 0.08 g/cm 3 , even more preferably at least 0.3 g/cm 3 . The expanded polymer can be any expanded polymer with dimensional stability when expanded and which provides structural integrity or acoustical sealing properties. Preferred examples of expanded polymers include expanded polyurethane, expanded polystyrene, expanded polyolefin, and expanded 2-part epoxy. A more preferred expanded polymer is an expanded polyurethane. The dimension of the expanded polymer is designed to be 3–6 mm smaller in each dimension than the size of the cavity to which it is to be inserted.
The one part adhesive comprises any one part adhesives which expands and bonds to the expanded foam and the material from which the interior of the vehicle cavity is made. The expandable adhesive that is used to coat the expandable polymer is prepared using a 1-part epoxy resin formulation. Preferred epoxy resins include diglycidyl ethers of bisphenol A and bisphenol F, as well as oligomers of diglycidyl ethers of bisphenol A and bisphenol F, either alone or in combination. More preferably, the epoxy resin is a mixture of diglycidyl ether of bisphenol A and an oligomer of diglycidyl ether of bisphenol A. The epoxy resin preferably constitutes from about 40 weight percent to about 80 weight percent of the total materials used to make the expandable adhesive.
The polymeric viscosity increasing agent is a polymer that increases the viscosity of the blend used to make the expandable adhesive to control the release and coalescence of gases produced by the blowing agent. The viscosity increasing agent is preferably used as a fine powder (volume mean average <200 μm) and preferably has a T g of at least 70° C. more preferably at least 100° C. Examples of polymeric viscosity increasing agents include polyvinyl butyrates; phenoxy resins, polystyrene, polycarbonates and polymeric acrylates and methacrylates and polyvinyl formal. Examples of more preferred polymeric viscosity increasing agents include polymeric acrylates and methacrylates, more preferably polymethylmethacrylate (PMMA), most preferably a carboxylic acid functionalized PMMA such as the commercially available Degalan™ 4944F PMMA (available from Rohm America). The polymeric viscosity increasing agent is used in an effective amount to control release of gas from the blowing agent so as to reduce cell size in the resultant cured resin. The concentration of the polymeric viscosity increasing agent is preferably at least 2, more preferably at least 5, and most preferably at least 10 weight percent; and preferably not more than 40 weight percent, more preferably not more than 30 weight percent, and most preferably not more than 20 weight percent, based on the total materials used to make the expandable adhesive.
The polymerization of the epoxy resin is catalyzed by an effective amount of a polymerizing promoting catalyst, preferably from about 0.1 weight percent to about 2 weight percent, based on the total materials used to make the expandable adhesive. Suitable catalysts include, but are not restricted to, ureas and imidazoles. An example of a preferred catalyst is Acclerine CEL 2191 (1-(2-(2-hydroxbenzamido)ethyl)-2-(2-hydroxyphenyl-2imidazoline, which has the following chemical structure:
The preparation of this catalyst is described by Bagga in U.S. Pat. No. 4,997,951, which description is incorporated herein by reference.
The epoxy resin is expanded to a desired volume in the presence of an effective amount of a blowing agent to achieve the desired foam structure and density, preferably from about 0.5 weight percent to about 10 weight percent, more preferably from about 0.5 to about 3 weigh percent, and most preferably from about 1 to about 2 weight percent, based on the total materials used to make the expandable adhesive. Preferred blowing agents are heat activatable at least about 100° C. more preferably at least about 120° C. and preferably not greater than about 160° C. Examples of suitable blowing agents include those described by Fukui in U.S. Pat. No. 6,040,350, column 4, lines 25–30, which section is incorporated herein by reference. An example of a preferred commercially available blowing agent is Celogen AZ™ 120 azodicarbonamide (both from Crompton).
The expandable adhesive may further comprise a known rheology control agent such as fumed silica. Surfactants can also be used in the expandable adhesives, such as silane or titanate based surfactants.
The epoxy resin is cured with an effective amount of a curing agent, preferably from about 2 to about 10 weight percent, based on the total materials used to make the expandable adhesive. Examples of suitable curing agents include those described by Fukui in column 4, line 66–67 and column 5, lines 1–9, which sections are incorporated herein by reference.
Preferred curing agents include dicyandiamide such as AMICURE CG-1200 (from Air Products).
A sufficient amount of curing agent is used to form the desired foam structure and to provide dimensional stability, preferably about 2 or greater of weight percent, even more preferably about 3 weight percent or greater, and most preferably about 4 weight percent or greater, and preferably about 10 weight percent or less, even more preferably about 8 weight percent or less and most preferably about 6 weight percent or less.
The expandable adhesive may also include any filler which has a small enough particle size for mixing may be used. The filler may be organic or inorganic. Among preferred organic fillers are polyethylene, polypropylene, polyurethane, rubber and polyvinyl butyral. Among preferred inorganic fillers are calcium carbonate, talc, silica, calcium metasilicate aluminum, hollow glass spheres, and the like. More preferred organic fillers are polyolefin polymeric fillers, such as a polyethylene copolymers. More preferred inorganic fillers include calcium carbonate. The amount of filler is preferably not greater than 25 parts by weight, more preferably not greater than 15 parts by weight, and most preferably not greater than 10 parts by weight, relative to 100 parts by weight of the epoxy resin used to make the expandable adhesive.
A preferred expandable adhesive is prepared by combining and mixing the epoxy resin, the blowing agent, the catalyst, the curing agent, the viscosity increasing agent, and optionally the fillers at a temperature above ambient temperature, preferably from about 30° C. to about 50° C. for about 15 minutes to about 2 hours. Entrapped air is removed in vacuo and the expandable adhesive is then injected into a hot mold (about 100° C. to about 130° C.) that surrounds and conforms to the shape of the expanded polymer to achieve variable designed thicknesses of adhesive over the expanded polymer ranging from about 1 mm to about 4 mm. The resultant foam insert is affixed within a cavity of an automotive structure so as to create about a 1-mm to about a 4-mm gap between the foam insert and the metal substrate. The metal structure is then e-coated, with residual e-coat liquid escaping through the gaps between foam insert and the metal. Finally, the e-coat and expandable adhesive are cured at a suitable curing temperature, preferably between about 150° C. and about 200° C.
The preferred cured (expanded) adhesive has a Young's modulus of at least 500 MPa, more preferably at least 700 MPa, and most preferably of at least 1000 MPa at 100% expansion. Furthermore, the preferred cured adhesive has surprisingly small voids, preferably with a number weighted mean diameter of less than 1000 μm, more preferably less than 500 μm, and most preferably less than 100 μm. Consequently, the adhesion of the foam insert to the automotive structure is strong and durable.
The following example is for illustrative purposes only and is not intended to limit the invention in any way. All percentages are weight percent unless otherwise specified.
EXAMPLE
Preparation of a Structural Foam Insert with Controlled Adhesive Cell Size
A rigid polyurethane foam having a density of 0.64 g/cm 3 and a Young's modulus of 400 MPa is conformed to a desired shape. An expandable adhesive is prepared by adding to a vessel with mixing DER 331 epoxy resin (40%), DER 337 epoxy resin (25%), CELOGEN AZ 120 blowing agent (1.5%), CaCO 3 filler (0.45%), carbon black (0.9%), ACCELERINE CEL 2191 catalyst (1%, obtained from Celerity LLC), AMICURE CG1200 dicydiamide, DEGALAN 4944F PMMA (12.1%), MICROTHENE FE-532 polyethylene copolymer (10%), and CABOSIL TS-720 (4.1%) at 40° C. for 1 hour. Entrapped air is then removed by mixing under vacuum for 30 minutes. The blend is injected into a hot mold (120° C.) surrounding and conforming to the shape of a polyurethane foam insert so that the expandable adhesive substantially covers the insert to achieve variable designed thicknesses ranging from 2–3 mm for designed variances in final mechanical properties of the expanded adhesive. The adhesive resides in the hot mold for 4 minutes, after which the mold is cooled to about room temperature over a 10-minute period and removed. The resultant FOAM INSERT is affixed within the cavity of an automotive structure to create about a 2-mm gap between the SFI and the metal substrate. The metal structure is e-coated at ambient temperatures, with the residual liquid running through the gaps between the SFI and the metal. The structure is heated in an oven for 40 minutes at about 180° C. to cure the e-coat and to expand and cure the adhesive. The cured adhesive has a Young's modulus of about 1033 MPa at 100% expansion. | An expandable adhesive for a structural foam insert useful for vehicular reinforcement is described. The adhesive is characterized by containing a viscosity enhancing agent such as a polymethylmethacrylate, which results in a cured adhesive having unusually small voids and unusually high Young's modulus. | 2 |
FIELD OF THE INVENTION
This invention relates to novel dye-bioconjugates for use in diagnosis and therapy, particularly novel compositions of cyanine dye bioconjugates of bioactive molecules.
BACKGROUND OF THE INVENTION
Cancer will continue to be a primary cause of death for the foreseeable future, but early detection of tumors would improve patient prognosis (R. T. Greenlee et al., Cancer statistics, 2000, CA Cancer J. Clin., 2000, 50, pp. 7-33). Despite significant advances in current methods for the diagnosis of cancer, physicians still rely on the presence of a palpable tumor mass. At this, however, the many benefits of early medical intervention may have been already compromised.
Photodiagnosis and/or phototherapy has a great potential to improve management of cancer patient (D. A. Benaron and D. K. Stevenson, Optical time - of - flight and absorbance imaging of biologic media , Science, 1993, 259, pp. 1463-1466; R. F. Potter (Series Editor), Medical optical tomography: functional imaging and monitoring , SPIE Optical Engineering Press, Bellingham, 1993; G. J. Tearney et al., In vivo endoscopic optical biopsy with optical coherence tomography , Science, 1997, 276, pp. 2037-2039; B. J. Tromberg et al., Non - invasive measurements of breast tissue optical properties using frequency—domain photon migration, Phil. Trans. Royal Society London B, 1997, 352, pp. 661-668; S. Fantini et al., Assessment of the size, position, and optical properties of breast tumors in vivo by non - invasive optical methods, Appl. Opt., 1998, 37, pp. 1982-1989; A. Pelegrin et al., Photoimmunodiagnosis with antibody - fluorescein coniugates: in vitro and in vivo preclinical studies, J. Cell Pharmacol., 1992, 3, pp. 141-145). These procedures use visible or near infrared light to induce the desired effect. Both optical detection and phototherapy have been demonstrated to be safe and effective in clinical settings and biomedical research (B. C. Wilson, Optical properties of tissues, Encyclopedia of Human Biology, 1991, 5, 587-597; Y-L. He et al., Measurement of blood volume using indocyanine green measured with pulse - spectrometry: Its reproducibility and reliability, Critical Care Medicine, 1998, 26, pp. 1446-1451; J. Caesar et al., The use of Indocyanine green in the measurement of hepatic blood flow and as a test of hepatic function, Clin. Sci., 1961, 21, pp. 43-57; R. B. Mujumdar et al., Cyanine dye labeling reagents: Sulfoindocyanine succinimidyl esters, Bioconjugate Chemistry, 1993, 4, pp. 105-111; U.S. Pat. No. 5,453,505; Eric Hohenschuh, et al., Light imaging contrast agents , WO 98/48846; Jonathan Turner, et al., Optical diagnostic agents for the diagnosis of neurodegenerative diseases by means of near infrared radiation, WO 98/22146; Kai Licha, et al., In - vivo diagnostic process by near infrared radiation , WO 96/17628; Robert A. Snow, et al., Compounds , WO 98/48838].
Dyes are important to enhance signal detection and/or photosensitizing of tissues in optical imaging and phototherapy. Previous studies have shown that certain dyes can localize in tumors and serve as a powerful probe for the detection and treatment of small cancers (D. A. Bellnier et al., Murine pharmacokinetics and antitumor efficacy of the photodynamic sensitizer 2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide- a, J. Photochem. Photobiol., 1993, 20, pp. 55-61; G. A. Wagnieres et al., In vivo fluorescence spectroscopy and imaging for oncological applications, Photochem. Photobiol., 1998, 68, pp. 603-632; J. S. Reynolds et al., Imaging of spontaneous canine mammary tumors using fluorescent contrast agents, Photochem. Photobiol., 1999, 70, pp. 87-94). However, these dyes do not localize preferentially in malignant tissues.
Efforts have been made to improve the specificity of dyes to malignant tissues by conjugating dyes to large biomolecules (A. Pelegrin, et al., Photoimmunodiagnosis with antibody - fluorescein conjugates: in vitro and in vivo preclinical studies, J. Cell Pharmacol., 1992, 3, pp. 141-145; B. Ballou et al., Tumor labeling in vivo using cyanine - coniugated monoclonal antibodies, Cancer Immunol. Immunother., 1995, 41, pp. 257-263; R. Weissleder et al., In vivo imaging of tumors with protease - activated near - infrared fluorescent probes, Nature Biotech., 1999, 17, pp. 375-378; K. Licha et al., New contrast agents for optical imaging: Acid - cleavable conjugates of cyanine dyes with biomolecules, Proc. SPIE, 1999, 3600, pp. 29-35). Developing a dye that can combine the roles of tumor-seeking, diagnostic, and therapeutic functions has been very difficult for several reasons. The dyes currently in use localize in tumors by a non-specific mechanism that usually relies on the lipophilicity of the dye to penetrate the lipid membrane of the cell. These lipophilic dyes require several hours or days to clear from normal tissues, and low tumor-to-normal tissue ratios are usually encountered. Furthermore, combining photodynamic properties with fluorescence emission needed for the imaging of deep tissues requires a molecule that must compromise either the photosensitive effect of the dye or the fluorescence quantum yield. Photosensitivity of phototherapy agents relies on the transfer of energy from the excited state of the agent to surrounding molecules or tissues, while fluorescence emission demands that the excitation energy be emitted in the form of light (T. J. Dougherty et al., Photoradiation therapy II: Cure of animal tumors with hematoporphyrin and light , Journal of National Cancer Institute, 1978, 55, pp. 115-121). Therefore, compounds and compositions that have optimal tumor-targeting ability to provide a highly efficient photosensitive agent for treatment of tumors are needed. Such agents would exhibit enhanced specificity for tumors and would also have excellent photophysical properties for optical detection.
Each of the references previously disclosed is expressly incorporated by reference herein in its entirety.
SUMMARY OF THE INVENTION
The invention is directed to a composition for a carbocyanine dye bioconjugate. The bioconjugate consists of three components: 1) a tumor specific agent, 2) a photosensitizer (phototherapy) agent, and 3) a photodiagnostic agent. The inventive bioconjugates use the multiple attachment points of carbocyanine dye structures to incorporate one or more receptor targeting and/or photosensitive groups in the same molecule. The composition may be used in various biomedical applications.
The invention is also directed to a method for performing a diagnostic and therapeutic procedure by administering an effective amount of the composition of the cyanine dye bioconjugate to an individual. The method may be used in various biomedical applications, such as imaging tumors, targeting tumors with anti-cancer drugs, and performing laser guided surgery.
BRIEF DESCRIPTION OF THE DRAWINGS
The file of this patent contains at least one drawing executed in color. Copies of this patent with color drawing(s) will be provided by the Patent and Trademark Office upon request and payment of the necessary fee.
FIG. 1 . shows representative structures of the inventive compounds.
FIG. 2 shows images taken at two minutes and 30 minutes post injection of indocyanine green into rats with various tumors.
FIG. 3 shows fluorescent images of a CA20948 tumor bearing rat taken at one and 45 minutes post administration of cytate.
FIG. 4 is a fluorescent image of a CA20948 tumor bearing rat taken at 27 hours post administration of cytate.
FIG. 5 shows fluorescent images of ex-vivo tissues and organs from a CA20948 tumor bearing rat at 27 hours post administration of cytate.
FIG. 6 is a fluorescent image of an AR42-J tumor bearing rat taken at 22 hours post administration of bombesinate.
DETAILED DESCRIPTION OF THE INVENTION
The invention relates to novel compositions comprising cyanine dyes having a general formula 1
wherein W 1 and W 2 may be the same or different and are selected from the group consisting of —CR 10 R 11 , —O—, —NR 12 , —S—, and —Se; Y 1 , Y 2 , Z 1 , and Z 2 are independently selected from the group consisting of hydrogen, tumor-specific agents, phototherapy agents, —CONH-Bm, —NHCO-Bm, —(CH 2 ) a —CONH-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH-Bm, —(CH 2 ) a —NHCO-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO-Bm, (CH 2 ) a —N(R 12 )—(CH 2 ) b —CONH-Bm, —(CH 2 ) a —N(R 12 )—(CH 2 ) c —NHCO-Bm, —(CH 2 ) a —N(R 12 )—CH 2 —(CH 2 OCH 2 ) b CH 2 —CONH-Bm, —(CH 2 ) a —N(R 12 )—CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —N(R 12 )—(CH 2 ) a —CONH-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —N(R 12 )—(CH 2 ) a —NHCO-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —N(R 12 )—CH 2 —(CH 2 OCH 2 ) d —CONH-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —N(R 12 )—CH 2 —(CH 2 OCH 2 ) d —NHCO-Bm, —CONH-Dm, —NHCO-Dm, —(CH 2 ) a —CONH-Dm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH-Dm, —(CH 2 ) a —NHCO-Dm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO-Dm, —(CH 2 ) a —N(R 12 )—(CH 2 ) b —CONH-Dm, —(CH 2 ) a —N(R 12 )—(CH 2 ) c —NHCO-Dm, —(CH 2 ) a —N(R 12 )—(CH 2 )—(CH 2 OCH 2 ) b —CH 2 —CONH-Dm, —(CH 2 ) a —N(R 12 )—CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO-Dm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —N(R 12 )—(CH 2 ) a —CONH-Dm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —N(R 12 )—(CH 2) a —NHCO-Dm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —N(R 12 )—(CH 2 OCH 2 ) d —CONH-Dm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —N(R 12 )—CH 2 —(CH 2 OCH 2 ) d —NHCO-Dm —(CH 2 ) a —NR 12 R 13 , and —CH 2 (CH 2 OCH 2 ) b —CH 2 NR 12 R 13 , K 1 and K 2 are independently selected from the group consisting of C 1 -C 30 alkyl, C 5 -C 30 aryl, C 1 -C 30 alkoxyl, C 1 -C 30 polyalkoxyalkyl, C 1 -C 30 polyhydroxyalkyl, C 5 -C 30 polyhydroxyaryl, C 1 -C 30 aminoalkyl, saccharides, peptides, —CH 2 (CH 2 OCH 2 ) b —CH 2 —, —(CH 2 ) a —CO—, —(CH 2 ) a —CONH—, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH—, —(CH 2 ) a —NHCO—, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO—, —(CH 2 ) a —O—, and —CH 2 —(CH 2 OCH 2 ) b —CO—; X 1 and X 2 are single bonds, or independently selected from the group consisting of nitrogen, saccharides, —CR 14 —, —CR 14 R 15 , —NR 16 R 17 ; C 5 -C 30 aryl; Q is a single bond or is selected from the group consisting of —O—, —S—, —Se—, and —NR 18 ; a 1 and b 1 independently vary from 0 to 5; R 1 to R 13 , and R 18 are independently selected from the group consisting of hydrogen, C 1 -C 10 alkyl, C 5 -C 20 aryl, C 1 -C 10 alkoxyl, C 1 -C 10 polyalkoxyalkyl, C 1 -C 20 polyhydroxyalkyl, C 5 -C 20 polyhydroxyaryl, C 1 -C 10 aminoalkyl, cyano, nitro, halogens, saccharides, peptides, —CH 2 (CH 2 OCH 2 ) b —CH 2 —OH, —(CH 2 ) a —CO 2 H, —(CH 2 ) a —CONH-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH-Bm, —(CH 2 ) a —NHCO-Bm, —(CH 2 —OCH 2 ) b —CH 2 —NHCO-Bm, —(CH 2 ) a —OH and —CH 2 —(CH 2 OCH 2 ) b —CO 2 H; R 14 to R 17 are independently selected from the group consisting of hydrogen, C 1 -C 10 alkyl, C 5 -C 20 aryl, C 1 -C 10 alkoxyl, C 1 -C 10 polyalkoxyalkyl, C 1 -C 20 polyhydroxyalkyl, C 5 -C 20 polyhydroxyaryl, C 1 -C 10 aminoalkyl, saccharides, peptides, —CH 2 (CH 2 OCH 2 ) b —CH 2 —, —(CH 2 ) a —CO—, —(CH 2 ) a —CONH—, CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH—, —(CH 2 ) a —NHCO—, —CH 2 —(CH 2 OCH 2 ) b —CH 2 NHCO—, —(CH 2 ) a —O—, and —CH 2 —(CH 2 OCH 2 ) b —CO—; Bm and Dm are independently selected from the group consisting of bioactive peptides, proteins, cells, antibodies, antibody fragments, saccharides, glycopeptides, peptidomimetics, drugs, drug mimics, hormones, metal chelating agents, radioactive or nonradioactive metal complexes, echogenic agents, photoactive molecules, and phototherapy agents (photosensitizers); a and c independently vary from 1 to 20; b and d independently vary from 1 to 100.
The invention also relates to the novel composition comprising carbocyanine dyes having a general formula 2
wherein W 1 , W 2 , Y 1 , Y 2 , Z 1 , Z 2 , K 1 , K 2 , Q, X 1 , X 2 , a 1 , and b 1 are defined in the same manner as in Formula 1; and R 19 to R 31 are defined in the same manner as R 1 to R 9 in Formula 1.
The invention also relates to the novel composition comprising carbocyanine dyes having a general formula 3
wherein A 1 is a single or a double bond; B 1 , C 1 , and D 1 are independently selected from the group consisting of —O—, —S—, —Se—, —P—, —CR 10 R 11 , —CR 11 , alkyl, NR 12 , and —C═O; A 1 , B 1 , C 1 , and D 1 may together form a 6- to 12-membered carbocyclic ring or a 6- to 12-membered heterocyclic ring optionally containing one or more oxygen, nitrogen, or sulfur atoms; and W 1 , W 2 , Y 1 , Z 1 , Z 2 , K 1 , K 2 , X 1 , X 2 , a 1 , b 1 and R 1 to R 12 are defined in the same manner as in Formula 1.
The present invention also relates to the novel composition comprising carbocyanine dyes having a general formula 4
wherein A 1 , B 1 , C 1 , and D 1 are defined in the same manner as in Formula 3; W 1 , W 2 , Y 1 , Y 2 , Z 1 , Z 2 , K 1 , K 2 , X 1 , X 2 , a 1 , and b 1 , are defined in the same as in Formula 1; and R 19 to R 31 are defined in the same manner as R 1 to R 9 in Formula 1.
The inventive biconjugates use the multiple attachment points of carbocyanine dye structures to incorporate one or more receptor targeting and/or photosensitive groups in the same molecule. More specifically, the inventive compositions consist of three components selected for their specific properties. One component, a tumor specific agent, is for targeting tumors. A second component, which may be a photosensitizer, is a phototherapy agent. A third component is a photodiagnostic agent.
Examples of the tumor targeting agents are bioactive peptides such as octreotate and bombesin (7-14) which target overexpressed receptors in neuroendocrine tumors. An example of a phototherapy agent is 2-[1-hexyloxyethyl]-2-devinylpyro-pheophorbide-a (HPPH, FIG. 1D, T═OH). Examples of photodiagnostic agents are carbocyanine dyes which have high infrared molar absorbtivities (FIG. 1 A-C). The invention provides each of these components, with their associated benefits, in one molecule for an optimum effect.
Such small dye biomolecule conjugates have several advantages over either nonspecific dyes or the conjugation of probes or photosensitive molecules to large biomolecules. These conjugates have enhanced localization and rapid visualization of tumors which is beneficial for both diagnosis and therapy. The agents are rapidly cleared from blood and non-target tissues so there is less concern for accumulation and for toxicity. A variety of high purity compounds may be easily synthesized for combinatorial screening of new targets, e.g., to identify receptors or targeting agents, and for the ability to affect the pharmacokinetics of the conjugates by minor structural changes.
The inventive compositions are useful for various biomedical applications. Examples of these applications include, but are not limited to: detecting, imaging, and treating of tumors; tomographic imaging of organs; monitoring of organ functions; performing coronary angiography, fluorescence endoscopy, laser guided surgery; and performing photoacoustic and sonofluorescent methods.
Specific embodiments to accomplish some of the aforementioned biomedical applications are given below. The inventive dyes are prepared according the methods well known in the art.
In two embodiments, the inventive bioconjugates have the formulas 1 or 2 where W 1 and W 2 may be the same or different and are selected from the group consisting of —C(CH 3 ) 2 , —C((CH 2 ) a OH)CH 3 , —C((CH 2 ) a OH) 2 , —C((CH 2 ) a —CO 2 H)CH 3 , —C((CH 2 ) a —CO 2 H) 2 , —C((CH 2 ) a NH 2 )CH 3 , —C((CH 2 ) a NH 2 ) 2 , —C((CH 2 ) a NR 12 R 13 ) 2 , —NR 12 , and —S—; Y 1 and Y 2 are selected from the group consisting of hydrogen, tumor-specific agents, —CONH-Bm, —NHCO-Bm, —(CH 2 ) a —CONH-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH-Bm, —(CH 2 ) a —NHCO-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO-Bm, —(CH 2 ) a —NR 12 R 13 and —CH 2 (CH 2 OCH 2 ) b —CH 2 NR 12 R 13 ; Z 1 and Z 2 are independently selected from the group consisting of hydrogen, phototherapy agents, —CONH-Dm, —NHCO-Dm, —(CH 2 ) a —CONH-Dm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH-Dm, —(CH 2 ) a —NHCO-Dm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO-Dm, —(CH 2 ) a —NR 12 R 13 , and —CH 2 (CH 2 OCH 2 ) b —CH 2 NR 12 R 13 ; K 1 and K 2 are independently selected from the group consisting of C 1 -C 10 alkyl, C 5 -C 20 aryl, C 1 -C 20 alkoxyl, C 1 -C 20 aminoalkyl, —(CH 2 ) a —CO—, —(CH 2 ) a —CONH, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH—, —(CH 2 ) a —NHCO—, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO—, and —CH 2 —(CH 2 OCH 2 ) b —CO—; X 1 and X 2 are single bonds, or are independently selected from the group consisting of nitrogen, —CR 14 —, —CR 14 R 15 , and —NR 16 R 17 ; Q is a single bond or is selected from the group consisting of —O—, —S—, and —NR 18 ; a, and b 1 independently vary from 0 to 3; Bm is selected from the group consisting of bioactive peptides containing 2 to 30 amino acid units, proteins, antibody fragments, mono- and oligosaccharides; Dm is selected from the group consisting of photosensitizers, photoactive molecules, and phototherapy agents; a and c independently vary from 1 to 20; and b and d independently vary from 1 to 100.
In two other embodiments, the bioconjugates according to the present invention have the formulas 3 or 4 wherein W 1 and W 2 may be the same or different and are selected from the group consisting of —C(CH 3 ) 2 , C((CH 2 ) a OH)CH 3 , —C((CH 2 ) a OH) 2 , —C((CH 2 ) a CO 2 H) 2 , —C((CH 2 ) a NH 2 )CH 3 , —C((CH 2 ) a NH 2 ) 2 , —C((CH 2 ) a NR 12 R 13 ) 2 , —NR 12 , and —S—; Y 1 and Y 2 are selected from the group consisting of hydrogen, tumor-specific agents, —CONH-Bm, —NHCO-Bm, —(CH 2 ) a —CONH-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH-Bm, —(CH 2 ) a NHCO-Bm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO-Bm, —(CH 2 ) a —NR 12 R 13 , and —CH 2 (CH 2 OCH 2 ) b —CH 2 NR 12 R 13 , Z 1 and Z 2 are independently selected from the group consisting of hydrogen, phototherapy agents, —CONH-Dm, —NHCO-Dm, —(CH 2 ) a —CONH-Dm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH-Dm, —(CH 2 ) a —NHCO-Dm, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO-Dm, —(CH 2 ) a —NR 12 R 13 , and —CH 2 (CH 2 OCH 2 ) b —CH 2 N R 12 R 13 ; K1 and K2 are independently selected from the group consisting of C 1 -C 10 alkyl, C 5 -C 20 aryl, C 1 -C 20 alkoxyl, C 1 -C 20 aminoalkyl, —(CH 2 ) a —CO—, —(CH 2 ) a —CONH, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —CONH—, —(CH 2 ) a —NHCO—, —CH 2 —(CH 2 OCH 2 ) b —CH 2 —NHCO—, and —CH 2 —(CH 2 OCH 2 ) b —CO—; X 1 and X 2 are single bonds or are independently selected from the group consisting of nitrogen, —CR 14 —, —CR 14 R 15 , and —NR 16 R 17 ; A 1 is a single or a double bond; B 1 , C 1 , and D 1 are independently selected from the group consisting of —O—, —S—, —CR 11 , alkyl, NR 12 , and —C═O; A 1 , B 1 , C 1 , and D 1 may together form a 6- to 12-membered carbocyclic ring or a 6- to 12-membered heterocyclic ring optionally containing one or more oxygen, nitrogen, or sulfur atoms; a 1 and b 1 independently vary from 0 to 3; Bm is selected from the group consisting of bioactive peptides containing 2 to 30 amino acid units, proteins, antibody fragments, mono- and oligosaccharides; bioactive peptides, protein, and oligosaccharide; Dm is selected from the group consisting of photosensitizers, photoactive molecules, and phototherapy agents; a and c independently vary from 1 to 20; and b and d independently vary from 1 to 100.
In one embodiment of the invention, the dye-biomolecule conjugates are useful for optical tomographic, endoscopic, photoacoustic and sonofluorescent applications for the detection and treatment of tumors and other abnormalities. These methods use light of wavelengths in the region of 300-1300 nm. For example, optical coherence tomography (OCT), also referred to as “optical biopsy,” is an optical imaging technique that allows high resolution cross sectional imaging of tissue microstructure. OCT methods use wavelengths of about 1280 nm.
In various aspects of the invention, the dye-biomolecule conjugates are useful for localized therapy for the detection of the presence or absence of tumors and other pathologic tissues by monitoring the blood clearance profile of the conjugates, for laser assisted guided surgery (LAGS) for the detection and treatment of small micrometastases of tumors, e.g., somatostatin subtype 2 (SST-2) positive tumors, upon laparoscopy, and for diagnosis of atherosclerotic plaques and blood clots.
In another embodiment, a therapeutic procedure comprises attaching a porphyrin or photodynamic therapy agent to a bioconjugate, and then administering light of an appropriate wavelength for detecting and treating an abnormality.
The compositions of the invention can be formulated for enteral or parenteral administration. These formulations contain an effective amount of the dye-biomolecule conjugate along with conventional pharmaceutical carriers and excipients appropriate for the type of administration contemplated. For example, parenteral formulations advantageously contain a sterile aqueous solution or suspension of the inventive conjugate, and may be injected directly, or may be mixed with a large volume parenteral composition or excipient for systemic administration as is known to one skilled in the art. These formulations may also contain pharmaceutically acceptable buffers and/or electrolytes such as sodium chloride.
Formulations for enteral administration may vary widely, as is well known in the art. In general, such formulations are aqueous solutions, suspensions or emulsions which contain an effective amount of a dye-biomolecule conjugate. Such enteral compositions may include buffers, surfactants, thixotropic agents, and the like. Compositions for oral administration may also contain flavoring agents and other ingredients for enhancing their organoleptic qualities.
The inventive compositions of the carbocyanine dye bioconjugates for diagnostic uses are administered in doses effective to achieve the desired effect. Such doses may vary widely, depending upon the particular conjugate employed, the organs or tissues which are the subject of the imaging procedure, the imaging equipment being used, and the like. The compositions may be administered either systemically, or locally to the organ or tissue to be imaged, and the patient is then subjected to diagnostic imaging and/or therapeutic procedures.
The present invention is further detailed in the following Examples, which are offered by way of illustration and are not intended to limit the scope of the invention in any manner.
EXAMPLE 1
Synthesis of Indocyaninebispropanoic Acid Dye (FIG. 1A, n=1)
A mixture of 1,1,2-trimethyl-[1H]-benz[e]indole (9.1 g, 43.58 mmoles) and 3-bromopropanoic acid (10.0 g, 65.37 mmoles) in 1,2-dichlorobenzene (40 ml) was heated at 110° C. for 12 hours. The solution was cooled to ambient temperature. The red residue obtained was filtered and washed with acetonitrile:diethyl ether (1:1 v/v ) mixture. The solid obtained was dried at ambient temperature under vacuum to give 10 g (64%) of light brown powder.
A portion of this solid (6.0 g; 16.56 mmoles), glutaconic aldehyde dianilide hydrochloride (Lancaster Synthesis, Windham, N.H.) (2.36 g, 8.28 mmoles), and sodium acetate trihydrate (2.93 g, 21.53 mmoles) in ethanol (150 ml) were refluxed for 90 minutes. After evaporating the solvent, 40 ml of a 2 N aqueous HCl was added to the residue. The mixture was centrifuged and the supernatant was decanted. This procedure was repeated until the supernatant became nearly colorless. About 5 ml of a water:acetonitrile (3:2 v/v ) mixture was added to the solid residue and lyophilized to obtain 2 g of dark green flakes. The purity of the compound was established with 1 H-nuclear magnetic resonance ( 1 H-NMR) and liquid chromatography/mass spectrometry (LC/MS) as is known to one skilled in the art.
EXAMPLE 2
Synthesis of Indocyaninebishexanoic Acid Dye (FIG. 1A n=4)
A mixture of 1,1,2-trimethyl-[1H]-benz[e]indole (20 g, 95.6 mmoles) and 6-bromohexanoic acid (28.1 g, 144.1 mmoles) in 1,2-dichlorobenzene (250 ml) was heated at 110 C for 12 hours. The green solution was cooled to ambient temperature and the brown solid precipitate that formed was collected by filtration. After washing the solid with 1,2-dichlorobenzene and diethyl ether, the brown powder obtained (24 g, 64%) was dried under vacuum at ambient temperature. A portion of this solid (4.0 g; 9.8 mmoles) glutacoaldehyde dianil monohydrochloride (1.4 g, 5 mmoles) and sodium acetate trihydrate (1.8 g, 12.9 mmoles) in ethanol (80 ml) were refluxed for 1 hour. After evaporating the solvent, 20 ml of 2 N aqueous HCl was added to the residue. The mixture was centrifuged and the supernatant was decanted. This procedure was repeated until the supernatant became nearly colorless. About 5 ml of a water:acetonitrile (3:2 v/v ) mixture was added to the solid residue and lyophilized to obtain about 2 g of dark green flakes. The purity of the compound was established with 1 H-NMR and LC/MS.
EXAMPLE 3
Synthesis of Peptides
Peptides of this invention were prepared by similar procedures with slight modifications in some cases.
Octreotate, an octapeptide, has the amino acid sequence D—Phe—Cys′—Tyr —D—Trp—Lys—Thr—Cys′—Thr (SEQ ID NO:1), wherein Cys′ indicates the presence of an intramolecular disulfide bond between two cysteine amino acids. Octreotate was prepared by an automated fluorenylmethoxycarbonyl (Fmoc) solid phase peptide synthesis using a commercial peptide synthesizer from Applied Biosystems (Model 432A SYNERGY Peptide Synthesizer). The first peptide cartridge contained Wang resin pre-loaded with Fmoc—Thr on a 25-μmole scale. Subsequent cartridges contained Fmoc-protected amino acids with side chain protecting groups for the following amino acids: Cys(Acm), Thr(t-Bu), Lys(Boc), Trp(Boc) and Tyr(t-Bu). The amino acid cartridges were placed on the peptide synthesizer and the product was synthesized from the C- to the N-terminal position according to standard procedures. The coupling reaction was carried out with 75 μmoles of the protected amino acids in the presence of 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HBTU)/N-hydroxybenzotriazole (HOBt). The Fmoc protecting groups were removed with 20% piperidine in dimethylformamide.
After the synthesis was complete, the thiol group was cyclized with thallium trifluoroacetate and the product was cleaved from the solid support with a cleavage mixture containing trifluoroacetic acid water:phenol:thioanisole (85:5:5:5 v/v ) for 6 hours. The peptide was precipitated with t-butyl methyl ether and lyophilized with water:acetonitrile (2:3 v/v ). The peptide was purified by HPLC and analyzed by LC/MS.
Octreotide, (D—Phe—Cys′—Tyr—D—Trp—Lys—Thr—Cys′—Thr—OH (SEQ ID NO:2)), wherein Cys′ indicates the presence of an intramolecular disulfide bond between two cysteine amino acids) was prepared by the same procedure as that for octreotate with no modifications.
Bombesin analogs were prepared by the same procedure but cyclization with thallium trifluoroacetate was omitted. Side-chain deprotection and cleavage from the resin was carried out with 50 μl each of ethanedithiol, thioanisole and water, and 850 μl of trifluoroacetic acid. Two analogues were prepared: Gly—Ser—Gly—Gln—Trp—Ala—Val—Gly—His—Leu—Met—NH 2 (SEQ ID NO:3) and Gly—Asp—Gly—Gln—Trp—Ala—Val—Gly—His—Leu—Met—NH 2 (SEQ ID NO:4).
Cholecystokinin octapeptide analogs were prepared as described for Octreotate without the cyclization step. Three analogs were prepared: Asp—Tyr—Met—Gly—Trp—Met—Asp—Phe—NH 2 (SEQ ID NO:5); Asp—Tyr—Nle—Gly—Trp—Nle—Asp—Phe—NH 2 (SEQ ID NO:6); and D—Asp—Tyr—Nle—Gly—Trp—Nle—Asp—Phe—NH 2 (SEQ ID NO:7) wherein Nle is norleucine.
Neurotensin analog (D—Lys—Pro—Arg—Arg—Pro—Tyr—Ile—Leu (SEQ ID NO:8)) was prepared as described for Octreotate without the cyclization step.
EXAMPLE 4
Synthesis of Peptide-Dye Conjugates (FIG. 1B, n=1, R 1 =Octreotate, R 2 ═R 1 or OH)
The method described below is for the synthesis of Octreotate-cyanine dye conjugates. Similar procedures were used for the synthesis of other peptide-dye conjugates.
Octreotate was prepared as described in Example 3, but the peptide was not cleaved from the solid support and the N-terminal Fmoc group of Phe was retained. The thiol group was cyclized with thallium trifluoroacetate and Phe was deprotected to liberate the free amine. Bisethylcarboxymethylindocyanine dye (53 mg, 75 μmoles) was added to an activation reagent consisting of a mixture 0.2 M HBTU/HOBt in DMSO (375 μl), and 0.2 M diisopropylethylamine in DMSO (375 μl). The activation was complete in about 30 minutes. The resin-bound peptide (25 μmoles) was then added to the dye. The coupling reaction was carried out at ambient temperature for 3 hours. The mixture was filtered and the solid residue was washed with DMF, acetonitrile and THF. After drying the green residue, the peptide was cleaved from the resin, and the side chain protecting groups were removed with a mixture of trifluoroacetic acid: water:thioanisole:phenol (85:5:5:5 v/v ). The resin was filtered and cold t-butyl methyl ether (MTBE) was used to precipitate the dye-peptide conjugate. The conjugate was dissolved in acetonitrile:water (2:3 v/v ) and lyophilized.
The product was purified by HPLC to give the monooctreotate-bisethylcarboxymethylindocyanine dye (Cytate 1, 80%, n=1, R 2 ═OH) and the bisoctreotate-bisethylcarboxymethylindocyanine dye (Cytate 2, 20%, n=1, R 1 ═R 2 ).
The monooctreotate conjugate may be obtained almost exclusively (>95%) over the bis conjugate by reducing the reaction time to 2 hours. This, however, leads to an incomplete reaction, and the free octreotate must be carefully separated from the dye conjugate in order to avoid saturation of the receptors by the non-dye conjugated peptide.
EXAMPLE 5
Synthesis of Peptide-Dye Conjugates (FIG. 1B, n=4 R 1 =octreotate R 2 ═R 1 or OH.
Octreotate-bispentylcarboxymethylindocyanine dye was prepared as described in Example 4 with some modifications. Bispentylcarboxymethylindocyanine dye (60 mg, 75 μmoles) was added to 400 μl activation reagent consisting of 0.2 M HBTU/HOBt and 0.2 M diisopropylethylamine in DMSO. The activation was complete in about 30 minutes and the resin-bound peptide (25 μmoles) was added to the dye. The reaction was carried out at ambient temperature for 3 hours. The mixture was filtered and the solid residue was washed with DMF, acetonitrile and THF. After drying the green residue, the peptide was cleaved from the resin and the side chain protecting groups were removed with a mixture of trifluoroacetic acid:water:thioanisole:phenol (85:5:5:5 v/v ). The resin was filtered and cold t-butyl methyl ether (MTBE) was used to precipitate the dye-peptide conjugate. The conjugate was dissolved in acetonitrile:water (2:3 v/v ) and lyophilized. The product was purified by HPLC to give octreotate-1,1,2-trimethyl-[1H]-benz[e]indole propanoic acid conjugate (10%), monooctreotate-bispentylcarboxymethylindocyanine dye (Cytate 3, 60%, n =4, R 2 ═OH) and bisoctreotate-bispentylcarboxymethylindocyanine dye (Cytate 4, 30%, n=4, R 1 ═R 2 ).
EXAMPLE 6
Synthesis of Peptide-Dye-Phototherapy Conjugates (FIG. 1B, n=4, R 1 =Octreotate, R 2 =HPPH) by Solid Phase
Bispentylcarboxymethylindocyanine dye (cyhex, 60 mg, 75 μmoles) in dichloromethane is reacted with cyanuric acid fluoride (21 mg, 150 mmoles) in the presence of pyridine (12 mg, 150 mmoles) for 30 minutes to produce an acid anhydride. One molar equivalent of 2-[1-hexyloxyethyl]-2-devinylpyropheophorbide-a (HPPH, FIG. 1D, T=—NHC 2 H 4 NH 2 ) is added to the anhydride to form the cyhex-HPPH conjugate with a free carboxylic acid group. This intermediate is added to an activation reagent consisting of a 0.2 M solution of HBTU/HOBt in DMSO (400 μl), and a 0.2 M solution of diisopropylethylamine in DMSO (400 μl). Activation of the carboxylic acid is complete in about 30 minutes. Resin-bound peptide (octreotate, 25 μmoles), prepared as described in Example 4, is added to the mixture. The reaction is carried out at ambient temperature for 8 hours. The mixture is filtered and the solid residue is washed with DMF, acetonitrile and THF. After drying the dark residue at ambient temperature, the peptide derivative is cleaved from the resin and the side chain protecting groups are removed with a mixture of trifluoroacetic acid:water:thioanisole:phenol (85:5:5:5 v/v ). After filtering the resin, cold t-butyl methyl ether (MTBE) is used to precipitate the dye-peptide conjugate, which is then lyophilized in acetonitrile:water (2:3 v/v ).
EXAMPLE 7
Synthesis of Peptide-Dye-Phototherapy Conjugates (FIG. 1B, n=4, R 1 =Octreotide, R 2 ═HPPH) by Solution Phase
Derivatized HPPH ethylenediamine (FIG. 1D, T=—NHC 2 H 4 NH 2 ; 1.1 molar equivalents) and lysine(trityl) 4 octreotide (1.2 molar equivalents) were added to a solution of bis(pentafluorophenyl) ester of cyhex (1 molar equivalent) in DMF. After stirring the mixture for 8 hours at ambient temperature, cold t-butyl methyl ether was added to precipitate the peptide conjugate. The crude product was purified by high performance liquid chromatography (HPLC).
EXAMPLE 8
Synthesis of Peptide-Dye-Phototherapy Conjugates (FIG. 1C, n=4, R 1 =K 0 -Octreotate, R 2 =HPPH, R 3 ═OH) by Solid Phase
Orthogonally protected Fmoc-lysine(Mtt) 0 Octreotate was prepared on a solid support, as described in Examples 3 and 4. The Fmoc group of Fmoc-lysine(Mtt) 0 is removed from the solid support with 20% piperidine in DMF. HPPH (FIG. 1 D,T=—OH), pre-activated with HBTU coupled to the free-amino group of lysine.
EXAMPLE 9
Imaging of Tumor Cell Lines With Indocyanine Green
A non-invasive in vivo fluorescence imaging apparatus was employed to assess the efficacy of indocyanine green (ICG) in three different rat tumor cell lines of the inventive contrast agents developed for tumor detection in animal models. A LaserMax Inc. laser diode of nominal wavelength 780 nm and nominal power of 40 mW was used. The detector was a Princeton Instruments model RTE/CCD-1317-K/2 CCD camera with a Rodenstock 10 mm F2 lens (stock #542.032.002.20) attached. An 830 nm interference lens (CVI Laser Corp., part #F10-830-4-2) was mounted in front of the CCD input lens, such that only emitted fluorescent light from the contrast agent was imaged.
Three tumor cell lines, DSL 6/A (pancreatic), Dunning R3327-H (prostate), and CA20948 (pancreatic), which are rich in somatostatin (SST-2) receptors were induced into male Lewis rats by solid implant technique in the left flank area (Achilefu et al., Invest. Radiology, 2000, pp. 479-485). Palpable masses were detected nine days post implant.
The animals were anesthetized with xylazine:ketamine:acepromazine (1.5:1.5:0.5 v/v ) at 0.8 ml/kg via intramuscular injection. The left flank was shaved to expose the tumor and surrounding surface area. A 21-gauge butterfly needle equipped with a stopcock connected to two syringes containing heparinized saline was placed into the tail vein of the rat. Patency of the vein was checked prior to administration of ICG. Each animal was administered a 0.5 ml dose of a 0.42 mg/ml solution of ICG in saline.
Two of the cell lines, DSL 6/A (pancreatic) and Dunning R3327-H (prostate) which are rich in somatostatin (SST-2) receptors indicated slow perfusion of the agent into the tumor over time. Images were taken at 2 minutes and 30 minutes post administration of ICG. Reasonable images were obtained for each. The third line, CA20948 (pancreatic), indicated only a slight and transient perfusion that was cleared after only 30 minutes post injection. This indicated that there was no non-specific localization of ICG into this tumor line compared to the other two lines which suggested a vastly different vascular architecture for this type of tumor (FIG. 2 ). The first two tumor lines (DSL 6/A and R3327-H) were not as highly vascularized as CA20948 which is also rich in somatostatin (SST-2) receptors. Consequently, the detection and retention of a dye in the CA20948 tumor model is an important index of receptor-mediated specificity.
EXAMPLE 10
Imaging of Rat Pancreatic Acinar Carcinoma (CA20948) With Cytate 1
The peptide, octreotate, is known to target somatostatin (SST-2) receptors. Therefore, the cyano-octreotates conjugate, Cytate 1, was prepared as described in Example 4. The pancreatic acinar carcinoma, CA20948, was induced into male Lewis rats as described in Example 9.
The animals were anesthetized with xylazine:ketamine:acepromazine (1.5:1.5:0.5 v/v ) at 0.8 ml/kg via intramuscular injection. The left flank was shaved to expose the tumor and surrounding surface area. A 21-gauge butterfly needle equipped with a stopcock connected to two syringes containing heparinized saline was placed into the tail vein of the rat. Patency of the vein was checked prior to administration of Cytate 1 via the butterfly apparatus. Each animal was administered a 0.5 ml dose of a 1.0 mg/ml solution of Cytate 1 in 25% (v/v) dimethylsulfoxide/water.
Using the CCD camera apparatus, dye localization in the tumor was observed. Usually, an image of the animal was taken pre-injection of contrast agent, and the pre-injection image was subsequently subtracted (pixel by pixel) from the post-injection images to remove background. However, the background subtraction was not done if the animal had been removed from the sample area and was later returned for imaging several hours post injection. These images demonstrated the specificity of cytate 1 for the SST-2 receptors present in the CA20948 rat tumor model.
At one minute post administration of cytate 1 the fluorescent image suggested the presence of the tumor in the left flank of the animal (FIG. 3 a ). At 45 minutes post administration, the image showed green and yellow areas in the left and right flanks and in the tail, however, there was a dark blue/blue green area in the left flank (FIG. 3 b ). AT 27 hours post administration of the conjugate, only the left flank showed a blue/blue green fluorescent area (FIG. 4 ).
Individual organs were removed from the CA20948 rat which was injected with cytate 1 and were imaged. High uptake of the conjugate was observed in the pancreas, adrenal glands and tumor tissue. Significant lower uptake was observed in heart, muscle, spleen and liver (FIG. 5 ). These results correlated with results obtained using radiolabeled octreotate in the same rat model system (M. de Jong, et al. Cancer Res. 1998, 58, 437-441).
EXAMPLE 11
Imaging of Rat Pancreatic Acinar Carcinoma (AR42-J) With Bombesinate
The AR42-J cell line is derived from exocrine rat pancreatic acinar carcinoma. It can be grown in continuous culture or maintained in vivo in athymic nude mice, SCID mice, or in Lewis rats. This cell line is particularly attractive for in vitro receptor assays, as it is known to express a variety of hormone receptors including cholecystokinin (CCK), epidermal growth factor (EGF), pituitary adenylate cyclase activating peptide (PACAP), somatostatin (sst 2 ) and bombesin.
In this model, male Lewis rats were implanted with solid tumor material of the AR42-J cell line in a manner similar to that described in Example 9. Palpable masses were present 7 days post implant, and imaging studies were conducted on animals when the mass had achieved approximately 2 to 2.5 g (10-12 days post implant).
FIG. 6 shows the image obtained with this tumor model at 22 hours post injection of bombesinate. Uptake of bombesinate was similar to that described in Example 10 for uptake of cytate 1 with specific localization of the bioconjugate in the tumor.
EXAMPLE 12
Imaging of Rat Pancreatic Acinar Carcinoma (CA20948) with Cytate 1 by Fluorescence Endoscopy
Fluorescence endoscopy is suitable for tumors or other pathologic conditions of any cavity of the body. It is very sensitive and is used to detect small cancerous tissues, especially in the lungs and gastrointestinal (GI) system. Methods and procedures for fluorescence endoscopy are well-documented [Tajiri H., et al. Fluorescent diagnosis of experimental gastric cancer using a tumor-localizing photosensitizer. Cancer Letters (1997) 111, 215-220; Sackmann M. Fluorescence diagnosis in GI endoscopy. Endoscopy (2000) 32, 977-985, and references therein].
The fluorescence endoscope consists of a small optical fiber probe inserted through the working channel of a conventional endoscope. Some fibers within this probe deliver the excitation light at 780 nm and others detect the fluorescence from the injected optical probe at 830 nm. The fluorescence intensity is displayed on a monitor.
Briefly, the CA20948 rat pancreatic tumor cells which are over-expressing somatostatin receptor are injected into the submucosa of a Lewis rat. The tumor is allowed to grow for two weeks. The rat is then anesthetized with xylazine:ketamine:acepromazine (1.5:1.5:0.5 v/v ) at 0.8 mL/kg via intramuscular injection. Cytate is injected in the tail vein of the rat and 60 minutes post-injection, the endoscope is inserted into the GI tract. Since cytate localizes in CA20948, the fluorescence intensity in the tumor is much higher than in the surrounding normal tissues. Thus, the relative position of the tumor is determined by observing the image on a computer screen.
EXAMPLE 13
Imaging of Rat Pancreatic Acinar Carcinoma (CA20948) with Cytate 1 by Photoacoustic Technique
The photoacoustic imaging technique combines optical and acoustic imaging to allow better diagnosis of pathologic tissues. The preferred acoustic imaging method is ultrasonography where images are obtained by irradiating the animal with sound waves. The dual ultrasonography and optical tomography enables the imaging and localization of pathologic conditions (e.g., tumors) in deep tissues. To enhance the imaging, cytate is incorporated into ultrasound contrast material. Methods for the encapsulation of gases in biocompatible shells that are used as the contrast material are described in the literature [Mizushige K., et al. Enhancement of ultrasound-accelerated thrombolysis by echo contrast agents: dependence on microbubble structure. Ultrasound in Med . & Biol . (1999), 25, 1431-1437]. Briefly, perfluorocarbon gas (e.g., perfluorobutane) is bubbled into a mixture of normal saline:propylene glycol:glycerol (7:1.5:1.5 v/v/v ) containing 7 mg/ml of cytate:dipalmitoylphosphatidylcholine:dipalmitoylphosphatidic acid, and dipalmitoylphosphatidylethanolamine-PEG 5,000 (1:7:1:1 mole %). The CA20948 tumor bearing Lewis rat is injected with 1 ml of the microbubbles and the agent is allowed to accumulate in the tumor. An optical image is obtained by exciting the near infrared dye at 780 nm and detecting the emitted light at 830 nm, as described in Examples 9-11. Ultrasonography is performed by irradiating the rat with sound waves in the localized tumor region and detecting the reflected sound as described in the literature [Peter J. A. Frinking, Ayache Bouakaz, Johan Kirkhorn, Folkert J. Ten Cate and Nico de Jong. Ultrasond contrast imaging: current and new potential methods. Ultrasound in Medicine & Biology (2000) 26 965-975].
EXAMPLE 14
Photodynamic Therapy (PDT) and Localized Therapy of Rat Pancreatic Acinar Carcinoma (CA20948) with Cytate-PDT Agent Bioconjugates
The method for photodynamic therapy is well documented in the literature [Rezzoug H., et al. In Vivo Photodynamic Therapy with meso-Tetra (m-hydroxyphenyl)chlorin (mTHPC): Influence of Light Intensity and Optimization of Photodynamic Efficiency. Proc. SPIE (1996), 2924, 181-86; Stranadko E., et al. Photodynamic Therapy of Recurrent Cancer of Oral Cavity, an Alternative to Conventional Treatment. Proc. SPIE (1996), 2924, 292-297]. A solution of the peptide dye-phototherapy bioconjugate is prepared as described in Example 7 (5 μmol/mL of 15% DMSO in water, 0.5 mL) and is injected into the tail vein of the tumor-bearing rat. The rat is imaged 24 hours post injection as described in Examples 9-11 to localize the tumor. Once the tumor region is localized, the tumor is irradiated with light of 700 nm (which corresponds to the maximum absorption wavelength of HPPH, the component of the conjugate that effects PDT). The energy of radiation is 10 J/cm 2 at 160 mW/cm 2 . The laser light is transmitted through a fiber optic, which is directed to the tumor. The rat is observed for 7 days and any decrease in tumor volume is noted. If the tumor is still present, a second dose of irradiation is repeated as described above until the tumor is no longer palpable.
For localized therapy, a diagnostic amount of cytate (0.5 mL/0.2 kg rat) is injected into the tail vein of the tumor-bearing rat and optical images are obtained as described in Examples 9-11. A solution of the peptide-dye-phototherapy bioconjugate is prepared as described in Example 7 (5 μmol/mL of 15% DMSO in water, 1.5 mL) and is injected directly into the tumor. The tumor is irradiated as described above.
EXAMPLE 15
Photodiagnosis with Atherosclerotic Plaques and Blood Clots
A solution of a peptide-dye-bioconjugate for targeting atherosclerotic plaques and associated blood clots is prepared as described in Example 7. The procedure for injecting the bioconjugate and subsequent localization and diagnosis of the plaques and clots is performed as described in Example 14.
While the invention has been disclosed by reference to the details of preferred embodiments of the invention, it is to be understood that the disclosure is intended in an illustrative rather than in a limiting sense, as it is contemplated that modifications will readily occur to those skilled in the art, within the spirit of the invention and the scope of the appended claims.
# SEQUENCE LISTING
<160> NUMBER OF SEQ ID NOS: 8
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<220> FEATURE:
<221> NAME/KEY: MOD RES
<222> LOCATION: (1)...(8)
<223> OTHER INFORMATION: Xaa at location 1 repr
#esents D-Phe. Artificial
sequence is completely synthesized.
<223> OTHER INFORMATION: Xaa at locations 2 and
# 7 represents Cys with an
intramolecular disulfide bond between
#two Cys
amino acids. Artificial sequence
#is completely synthesized.
<223> OTHER INFORMATION: Xaa at location 4 repr
#esents D-Trp. Artificial
sequence is completely synthesized.
<400> SEQUENCE: 1
Xaa Xaa Tyr Xaa Lys Thr Xaa Thr
1 5
<210> SEQ ID NO 2
<211> LENGTH: 8
<212> TYPE: PRT
<213> ORGANISM: Artificial Sequence
<220> FEATURE:
<221> NAME/KEY: MOD RES
<222> LOCATION: (1)...(8)
<223> OTHER INFORMATION: Xaa at location 1 repr
#esents D-Phe. Artificial
sequence is completely synthesized.
<223> OTHER INFORMATION: Xaa at locations 2 and
# 7 represents Cys with an
intramolecular disulfide bond between
#two Cys
amino acids. Artificial sequence
#is completely synthesized.
<223> OTHER INFORMATION: Xaa at location 4 repr
#esents D-Trp. Artificial
sequence is
completely synthesized.
<223> OTHER INFORMATION: Xaa at location 8 repr
#esents Thr-OH. Artificial
sequence is completely synthesized.
<400> SEQUENCE: 2
Xaa Xaa Tyr Xaa Lys Thr Xaa Xaa
1 5
<210> SEQ ID NO 3
<211> LENGTH: 11
<212> TYPE: PRT
<213> ORGANISM: Unknown
<220> FEATURE:
<221> NAME/KEY: MOD RES
<222> LOCATION: (1)...(11)
<223> OTHER INFORMATION: Bom
besin ana
<400> SEQUENCE: 3
Gly Ser Gly Gln Trp Ala Val Gly His Leu Me
#t
1 5
# 10
<210> SEQ ID NO 4
<211> LENGTH: 11
<212> TYPE: PRT
<213> ORGANISM: Unknown
<220> FEATURE:
<221> NAME/KEY: MOD RES
<222> LOCATION: (1)...(11)
<223> OTHER INFORMATION: Bombesin analog
<400> SEQUENCE: 4
Gly Asp Gly Gln Trp Ala Val Gly His Leu Me
#t
1 5
# 10
<210> SEQ ID NO 5
<211> LENGTH: 8
<212> TYPE: PRT
<213> ORGANISM: Unknown
<220> FEATURE:
<221> NAME/KEY: MOD RES
<222> LOCATION: (1)...(8)
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#analogs
<400> SEQUENCE: 5
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<213> ORGANISM: Artificial Sequence
<220> FEATURE:
<221> NAME/KEY: MOD RES
<222> LOCATION: (1)...(8)
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#nthesized.
<400> SEQUENCE: 6
Asp Tyr Xaa Gly Trp Xaa Asp Phe
1 5
<210> SEQ ID NO 7
<211> LENGTH: 8
<212> TYPE: PRT
<213> ORGANISM: Artificial Sequence
<220> FEATURE:
<221> NAME/KEY: MOD RES
<222> LOCATION: (1)...(8)
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#esents D-Asp.
Artificial sequence is completely sy
#nthesized.
<223> OTHER INFORMATION: Xaa at locations 3 and
# 6 represents Norleucine.
Artificial sequence is completely
#synthesized.
<400> SEQUENCE: 7
Xaa Tyr Xaa Gly Trp Xaa Asp Phe
1 5
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<212> TYPE: PRT
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<221> NAME/KEY: MOD RES
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#esents D-Lys.
Artificial sequence is completely sy
#nthesized.
<400> SEQUENCE: 8
Xaa Pro Arg Arg Pro Tyr Ile Leu
1 5 | Novel tumor specific phototherapeutic and photodiagnostic agents are disclosed. The compounds consist of a carbocyanine dye for visualization, photosensitizer for photodynamic treatment, and tumor receptor-avid peptide for site-specific delivery of the probe and phototoxic agent to diseased tissues A combination of these elements takes full advantage of the unique and efficient properties of each component for an effective patient care management. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. §119 from U.S. Provisional Application No. 62/054,485, entitled “Control Signaling in a Beamforming System,” filed on Sep. 24, 2014; U.S. Provisional Application No. 62/054,488, entitled “Synchronization in a Beamforming System,” filed on Sep. 24, 2014, the subject matter of which is incorporated herein by reference.
TECHNICAL FIELD
The disclosed embodiments relate generally to wireless communication, and, more particularly, to control signaling and synchronization in a Millimeter Wave (mmW) beamforming system.
BACKGROUND
The bandwidth shortage increasingly experienced by mobile carriers has motivated the exploration of the underutilized Millimeter Wave (mmW) frequency spectrum between 3G and 300G Hz for the next generation broadband cellular communication networks. The available spectrum of mmW band is two hundred times greater than the conventional cellular system. The mmW wireless network uses directional communications with narrow beams and can support multi-gigabit data rate. The underutilized bandwidth of the mmW spectrum has wavelengths ranging from 1 mm to 100 mm. The very small wavelengths of the mmW spectrum enable large number of miniaturized antennas to be placed in a small area. Such miniaturized antenna system can produce high beamforming gains through electrically steerable arrays generating directional transmissions.
With recent advances in mmW semiconductor circuitry, mmW wireless system has become a promising solution for real implementation. However, the heavy reliance on directional transmissions and the vulnerability of the propagation environment present particular challenges for the mmW network. In general, a cellular network system is designed to achieve the following goals: 1) Serve many users with widely dynamical operation conditions simultaneously; 2) Robust to the dynamics in channel variation, traffic loading and different QoS requirement; and 3) Efficient utilization of resource such as bandwidth and power. Beamforming adds to the difficulty in achieving these goals. A robust control-signaling scheme is thus required to facilitate the beamforming operation in a challenging environment.
In cellular networks, pilot signals are needed for device identification and time-frequency synchronization. Primary synchronization signal is a unique signal with smaller search space, which can be used for first stage synchronization to achieve coarse frame boundary and frequency synchronization. Secondary synchronization signal is a unique signal with larger search space, which can be used for second stage synchronization to identify device and achieve fine (symbol level) timing and frequency synchronization. Reference signal is used for channel estimation and demodulation of data symbols. The three types of pilot signals for time-frequency synchronization and channel estimation introduce too much overhead. Furthermore, spatial synchronization is not considered in existing solutions (e.g., LTE). Future systems operate in much higher carrier frequency band that requires beamforming with very narrow beam width. As a result, synchronization signals need to align with TX and RX beams under spatial synchronization.
A beamforming system synchronization architecture is sought to allow the receiving devices to synchronize to the transmitting devices in time, frequency, and spatial domains in the most challenging situation.
SUMMARY
A beamforming system synchronization architecture is proposed to allow the receiving device to synchronize to the transmitting device in time, frequency, and spatial domain in the most challenging situation with very high pathloss. A periodically configured time-frequency resource blocks in which the transmitting device uses the same beamforming weights for its control beam transmission to the receiving device. A pilot signal for each of the control beams is transmitted in each of the periodically configured time-frequency resource blocks. The same synchronization signal can be used for all stages of synchronization including initial coarse synchronization, device and beam identification, and channel estimation for data demodulation. Pilot symbols are inserted into pilot structures and repeated for L times in each pilot structure. The L repetitions can be implemented by one or more Inverse Fast Fourier Transfers (IFFTs) with corresponding one or more cyclic prefix (CP) lengths. A detector at the receiving device detects the presence of the control beams, synchronizes to the transmission and estimates the channel response by receiving the pilot signals. The detector at the receiving device has low complexity when exploiting the structure of the synchronization signals. It consists of three stages that break down the synchronization procedure into less complicated steps. It accurately estimates the parameters required for identifying the transmit device and performing subsequent data communication.
In one embodiment, a base station allocates a set of control resource blocks in a beamforming OFDM network. The set of control resource blocks comprises periodically allocated time-frequency resource blocks associated with a set of beamforming weights to form a control beam. The base station partitions each resource block into a pilot part and a data part. Each pilot part is divided into M pilot structures and each pilot structure comprises L OFDM symbols. Pilot symbols are inserted once every K subcarriers for R times in each of the L OFDM symbol to form the pilot part while data symbols are inserted in the remaining resource elements to form the data part. The variables M, L, K, and R are all positive integers. The base station then transmits the pilot symbols and the data symbols via the control beam to a plurality of user equipments (UEs). The M pilot structures have a similar structure with a different offset ν m and a different sequence s m . Each control beam of a cell is identified by the pilot symbols having a hopping pattern based on ν m and a signature sequence s m . Specifically, for the j-th control beam of the i-th cell, there is a corresponding identifier pair ν m (i,j) and s m (i,j)[n].
In another embodiment, a base station allocates time-frequency resource blocks in a beamforming OFDM network for control beam (CB) transmission. The base station partitions each resource block into a pilot part and a data part. The pilot part comprises M pilot structures and each pilot structure comprises a number of OFDM symbols in time domain and a number of subcarriers in frequency domain. The base station then inserts pilot symbols of a pilot signal in each OFDM symbol in the pilot part. The pilot symbols are repeated for L times in each pilot structure, and each pilot structure is applied by one or more Inverse Fast Fourier Transfers (IFFTs) with corresponding one or more variable cyclic prefix (CP) lengths for CB transmission. A user equipment (UE) receives control beam transmission from the base station. The UE receives a time domain signal from pilot symbols that are transmitted over periodically allocated time-frequency resource blocks of a control beam. The UE processes the time domain signal by removing one or more cyclic prefixes (CPs) with a variable CP length and performing corresponding one or more variable-length Fast Fourier Transfers (FFTs) to reconstruct a pilot part of a resource block, wherein the pilot part comprises M pilot structures and each pilot structure comprises a number of OFDM symbols in time domain and a number of subcarriers in frequency domain. The UE then extracts the pilot symbols from each pilot structure. The pilot symbols are repeated for L times in each pilot structure.
In yet another embodiment, a user equipment (UE) receives control beam transmissions from a base station in a beamforming OFDM network. A pilot signal is transmitted over periodically allocated time-frequency resource blocks of a control beam in a cell. The UE processes pilot symbols carried in a pilot part of a resource block, the pilot part comprises M pilot structures and each pilot structure comprises L OFDM symbols in time domain and R subcarriers in frequency domain. The pilot symbols are inserted once every K subcarriers for R times in each OFDM symbol, and M, L, R, and K are positive integers. The UE then detects the control beam and the pilot signal based on the control beam transmission.
Other embodiments and advantages are described in the detailed description below. This summary does not purport to define the invention. The invention is defined by the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, where like numerals indicate like components, illustrate embodiments of the invention.
FIG. 1 illustrates control beams in a beamforming system in accordance with one novel aspect.
FIG. 2 is a simplified block diagram of a base station and a user equipment that carry out certain embodiments of the present invention.
FIG. 3 illustrates beamforming weights applied to multiple antenna elements in a beamforming system.
FIG. 4 illustrates multiple sets of beamforming weights applied to antenna elements one beam at a time or two beams at a time.
FIG. 5 illustrates spatial reciprocity of DL and UL transmission in a beamforming system.
FIG. 6 illustrates control beams in a cell comprising DL control resource blocks and UL control resource blocks.
FIG. 7 illustrates one embodiment of DL control resource block associated with a control beam.
FIG. 8 illustrates one embodiment of UL control resource block associated with a control beam.
FIG. 9 illustrates BS transmission and UE reception in DL control resource blocks.
FIG. 10 illustrates UE transmission and BS reception in UL control resource blocks.
FIG. 11 illustrates control beams in a cell comprising DL and UL control resource blocks and their associated beamforming weights.
FIG. 12 illustrates control region, control region segment, and control cycle of a control beam.
FIG. 13 illustrates control region segment and control resource block configuration.
FIG. 14 illustrates a preferred embodiment of DL and UL control resource block configuration.
FIG. 15 illustrates an UL receiver having two RF chains for receiving two control beams simultaneously.
FIG. 16A illustrates embodiments with and without interleaved DL/UL control resource configuration.
FIG. 16B illustrates one embodiment of control resource configuration with different DL/UL duty cycles.
FIG. 17 illustrates embodiments of control cycles for different cells.
FIG. 18 illustrates embodiments of control cycles in TDD and FDD systems.
FIG. 19 illustrates a control signaling procedure between a UE and a BS in a beamforming system in accordance with one novel aspect.
FIG. 20 is a flow chart of a method of control signaling from base station perspective in a beamforming system in accordance with one novel aspect.
FIG. 21 is a flow chart of a method of control signaling from user equipment perspective in a beamforming system in accordance with one novel aspect.
FIG. 22 illustrates one example of pilot signals in a control beam in a beamforming system in accordance with one novel aspect.
FIG. 23 illustrates a detailed example of pilot structures in control beams.
FIG. 24 illustrates control beam identification based on pilot signals.
FIG. 25 illustrates variations of pilot structures with additional OFDM symbols.
FIG. 26 illustrates variations of pilot structures with guard time.
FIG. 27 is a flow chart of a method of allocating resources for pilot symbol transmission in a beamforming system in accordance with one novel aspect.
FIG. 28 illustrates different embodiments of OFDM symbols with repetitions in time domain.
FIG. 29 illustrates pilot structures with variable cyclic prefix length and variable length FFT.
FIG. 30 is a flow chart of supporting variable CP length for pilot signal transmission in a beamforming network in accordance with one novel aspect.
FIG. 31 is a flow chart of supporting variable CP length for pilot signal reception in a beamforming network in accordance with one novel aspect.
FIG. 32 illustrates a three-stage pilot signal detection procedure in accordance with one novel aspect.
FIG. 33 illustrates a stage-1 control beam detection and coarse time-frequency estimation.
FIG. 34 illustrates a stage-2 control beam reference block boundary detection.
FIG. 35 illustrates a stage-3 sequence correlation and beam identification and fine time-frequency synchronization.
FIG. 36 is a flow chart of a method of pilot signal detection based on control beam transmission in a beamforming network in accordance with one novel aspect.
DETAILED DESCRIPTION
Reference will now be made in detail to some embodiments of the invention, examples of which are illustrated in the accompanying drawings.
FIG. 1 illustrates control beams in a beamforming Millimeter Wave (mmWave) cellular network 100 in accordance with one novel aspect. Beamforming network 100 comprises a base station BS 101 and a user equipment UE 102 . The mmWave cellular network uses directional communications with narrow beams and can support multi-gigabit data rate. Directional communications are achieved via digital and/or analog beamforming, wherein multiple antenna elements are applied with multiple sets of beamforming weights to form multiple beams. For control purpose, a set of coarse TX/RX control beams are provisioned by the base station in the cellular system. The set of control beams may be periodically configured or occur indefinitely and repeatedly in order known to the UEs. The set of control beams covers the entire cell coverage area with moderate beamforming gain. Each control beam broadcasts a minimum amount of beam-specific information similar to Master Information Block or System Information Block (MIB or SIB) in LTE. Each beam may also carry UE-specific control or data traffic. Each beam transmits a set of known signals for the purpose of initial time-frequency synchronization, identification of the control beam that transmits the signals, and measurement of radio channel quality for the beam that transmits the signals.
In the example of FIG. 1 , BS 101 is directionally configured with multiple cells, and each cell is covered by a set of coarse TX/RX control beams. In one embodiment, cell 110 is covered by eight control beams CB 0 to CB 7 . Each control beam comprises a set of downlink resource blocks, a set of uplink resource blocks, and a set of associated beamforming weights with moderate beamforming gain. In the example of FIG. 1 , different control beams are time division multiplexed (TDM) in time domain. A downlink subframe 121 has eight DL control beams occupying a total of 0.38 msec. An uplink subframe 122 has eight UL control beams occupying a total of 0.38 msec. The interval between the DL subframe and the UL subframe is 2.5 msec. The set of control beams are lower-level control beams that provide low rate control signaling to facilitate high rate data communication on higher-level data beams. For example, UE 102 performs synchronization with BS 101 via control beam CB 4 , and exchanges data traffic with BS 101 via dedicated data beam DB 0 . The control beam and data beam architecture provides a robust control-signaling scheme to facilitate the beamforming operation in mmWave cellular network systems.
FIG. 2 is a simplified block diagram of a base station and a user equipment that carry out certain embodiments of the present invention. BS 201 has an antenna array 211 having multiple antenna elements that transmits and receives radio signals, one or more RF transceiver modules 212 , coupled with the antenna array, receives RF signals from antenna 211 , converts them to baseband signal, and sends them to processor 213 . RF transceiver 212 also converts received baseband signals from processor 213 , converts them to RF signals, and sends out to antenna 211 . Processor 213 processes the received baseband signals and invokes different functional modules to perform features in BS 201 . Memory 214 stores program instructions and data 215 to control the operations of BS 201 . BS 201 also includes multiple function modules that carry out different tasks in accordance with embodiments of the current invention.
Similarly, UE 202 has an antenna 231 , which transmits and receives radio signals. A RF transceiver module 232 , coupled with the antenna, receives RF signals from antenna 231 , converts them to baseband signals and sends them to processor 233 . RF transceiver 232 also converts received baseband signals from processor 233 , converts them to RF signals, and sends out to antenna 231 . Processor 233 processes the received baseband signals and invokes different functional modules to perform features in UE 202 . Memory 234 stores program instructions and data 235 to control the operations of UE 202 . UE 202 also includes multiple function modules that carry out different tasks in accordance with embodiments of the current invention.
The functional modules can be implemented and configured by hardware, firmware, software, and any combination thereof. For example, from BS side, DL allocation module 221 and UL allocation module 222 allocates control radio resource blocks for the control beams, and pilot allocation module 223 allocates radio resources for transmitting pilot signals. Note that the term “allocate” can be an explicit action performed by the BS to configure and reserve certain resource blocks, but it can also be an implicit action of following a predefined agreement based on a standard specification. From UE side, pilot detection module 245 detects pilot signals, extract pilot symbols, and identify control beams from received control beam transmission, beam selection module 244 selects a preferred control beam from received control beam transmission, synchronization module 243 performs time and frequency synchronization with the BS using the selected control beam, measurement module 242 measures radio signals for different control beams and cells, and random access module 241 performs channel access for establishing connection with the BS.
FIG. 3 illustrates beamforming weights applied to multiple antenna elements in a beamforming system. Through directional antenna technology, complex beamforming weights are adjusted and then applied to the signals transmitted or received by the multiple antenna elements to focus the transmitting or receiving radiation power to the desire direction. The beamforming weights W can be applied in analog domain in the RF chain Nc (e.g., as illustrated in FIG. 3 ), or applied in digital domain at the baseband (not shown) depending on the transceiver architecture. Multiple sets of complex weights can be applied to the multiple antenna elements Nt, forming one beam at a time or multiple beams simultaneously.
FIG. 4 illustrates multiple sets of beamforming weights applied to antenna elements to form one beam at a time or two beams at a time. In the top row of FIG. 4 , the base station forms one beam at a time by applying one set of weights. Beams 0 , 1 , 2 , and 3 are sequentially formed one at a time. In the bottom row of FIG. 4 , the base station forms two beams at a time by applying two sets of weights. Beams 0 / 4 , 1 / 5 , 2 / 6 , and 3 / 7 are sequentially formed two at a time.
FIG. 5 illustrates spatial reciprocity of DL and UL transmission in a beamforming system. It is generally assumed that the downlink channel and the uplink channel is spatially reciprocal in the beamforming system. This is typically true for Time division duplex (TDD) systems and for most Frequency division duplex (FDD) systems if the frequency spacing is less than tenth of the total channel bandwidth. Under spatially reciprocal beamforming, the same beamformed antenna pattern is used for reception and transmission. As illustrated in FIG. 5 , for downlink transmission, the BS applies TX beamforming vector V BS,TX and the UE applies RX beamforming vector V UE,RX . For uplink transmission, the BS applies RX beamforming vector V BS,RX and the UE applies TX beamforming vector V UE,TX . Under spatially reciprocal beamforming, the beamforming vectors for downlink and uplink are the same, e.g., (V BS,TX , V UE,RX )=(V BS,RX , V UE,TX ).
FIG. 6 illustrates control beams in a cell comprises DL control resource blocks and UL control resource blocks and associated beamforming vectors. As a general concept, a downlink control beam is defined as a set of time-frequency resource blocks in which the base station uses the same beamforming weights set for its downlink transmission to the receiving UEs. The said time-frequency resource blocks, referred to as downlink (DL) control resource blocks, may be periodically configured or occur indefinitely in order known to the UEs. The periodically configured downlink control resource blocks for downlink control beam CB 0 is depicted in the top half diagram of FIG. 6 , where V 0 BS,TX represents the beamforming vector for downlink CB 0 .
Similarly, an uplink control beam is defined as a set of time-frequency resource blocks in which the base station preferably chooses the same beamforming weights set as the one used by the corresponding DL control resource blocks for its reception of the UEs' uplink transmission. The said time-frequency resource blocks, referred to as uplink (UL) control resource blocks, may be periodically configured or occur indefinitely in order known to the UEs. The periodically configured uplink control resource blocks for uplink control beam CB 0 is depicted in the bottom half diagram of FIG. 6 , where V 0 BS,RX represents the beamforming vector for uplink CB 0 . Because of spatial reciprocity, the beamforming vectors are the same (V 0 BS,TX =V 0 BS,RX ). If the base station chooses not to use the corresponding transmit beamforming weights set as its receive beamforming weights set in the UL control resource block, then it should use a beamforming weights set that achieves better performance than the beamforming weights set associated with the DL control resource blocks.
FIG. 7 illustrates one embodiment of a DL control resource block associated with a control beam. Each DL control resource block associated with a control beam comprises at least a pilot part and a data part transmitted by the base station. For example, DL control resource block 701 comprises pilot part 710 and data part 720 . The pilot part is used for identification of the cell and the control beam, and for time, frequency, and spatial synchronization. The data part is used for cell-specific broadcast, beam-specific broadcast, UE-specific control data, and UE-specific traffic data.
FIG. 8 illustrates one embodiment of an UL control resource block associated with a control beam. Each UL control resource block comprises resources allocated to a certain UE. The transmission of a UE in the UL control resource block comprises at least a pilot part and a data part. For example, UL control resource block 801 comprises resources 802 that includes pilot part 810 and data part 820 . The pilot part is used for identification of the UE, and for the base station to achieve time, frequency, and spatial synchronization to the UE's uplink transmission. The data part is used for UE-specific control data and UE-specific traffic data.
The transmission of a UE in the UL control resource block may employ transmit beamforming when equipped with multiple antennas. The transmit beamforming weights set used by the UE for the transmitting in the UL control resource block should preferably be the same as the receive beamforming weights set used by the UE for the reception in the preceding DL control resource block with which the UL transmission is associated.
FIG. 9 illustrates BS transmission and UE reception in DL control resource blocks. FIG. 10 illustrates UE transmission and BS reception in UL control resource blocks. Under spatially reciprocal beamforming, the same beamformed antenna pattern is used for reception and transmission. As illustrated in FIG. 9 , for downlink transmission with control beam CB 0 , the BS applies TX beamforming vector V 0 BS,TX and the UE applies RX beamforming vector V 0 UE,RX in DL control resource blocks. As illustrated in FIG. 10 , for uplink transmission with CB 0 , the BS applies RX beamforming vector V 0 BS,RX and the UE applies TX beamforming vector V 0 UE,TX in UL control resource blocks. Under spatially reciprocal beamforming, the beamforming vectors of control beam CB 0 for downlink and uplink are the same, e.g., V 0 BS,RX =V 0 BS,TX for the base station and V 0 UE,TX =V 0 UE,RX for the UE.
FIG. 11 illustrates control beams in a cell comprising DL and UL control resource blocks and their associated beamforming weights. The set of DL and UL control resource blocks and their associated beamforming weights set are collectively referred to as a Control Beam (CB) in a cell. Multiple sets of beamforming weights create radiation patterns covering the entire service area of the cell. One set of DL control resource blocks and one set of UL control resource blocks are associated with each of the beamforming weights set. Each cell has multiple control beams covering its entire service area. In the example of FIG. 11 , control beam 0 (CB 0 ) in cell 1100 comprises a set of DL control resource blocks 1110 , a set of UL control resource blocks 1120 , and a set of corresponding beamforming weights or beamforming vectors (V 0 BS,TX =V 0 BS,RX =V 0 BS ). The base station allocates eight control beams from CB 0 to CB 7 for cell 1100 . CB 0 is associated with beamforming vectors V 0 BS , CB 1 is associated with beamforming vectors V 1 BS , and so on so forth. The collection of the eight beamforming vectors V 0 BS through V 7 BS creates a radiation pattern covering the entire service area of the cell.
FIG. 12 illustrates control region, control region segment, and control cycle of a control beam. The collection of all DL control resource blocks associated with all control beams in a cell is referred to as the DL control region of a cell. DL control region may further be divided into DL control region segments. A DL control region segment comprises DL control resource blocks associated with all or part of the control beams in a cell within a certain time period referred to as the control cycle of the cell. Similarly, the collection of all UL control resource blocks associated with all control beams in a cell is referred to as the UL control region of a cell. UL control region may further be divided into UL control region segments. A UL control region segment comprises UL control resource blocks associated with all or part of the control beams in a cell within the control cycle of the cell. There is one DL control segment and one corresponding UL control segment in a control cycle of a cell. The control cycle of the cell may be pre-configured and known to the UEs or dynamically configured and signaled to or blindly detected by the UEs. The control cycle may vary over time.
In the example of FIG. 12 , the top half of the diagram depicts the DL control region having three DL control region segments. Each DL control region segment comprises DL control resource blocks for control beams CB 0 , CB 1 , CB 2 , CB 3 , and CB 4 . The bottom half of the diagram depicts the UL control region having two UL control region segments. Each UL control region segment comprises UL control resource blocks for control beams CB 0 , CB 1 , CB 2 , CB 3 , and CB 4 . A control cycle, e.g., from time T 0 to T 1 , comprises one DL control region segment 1210 and one UL control region segment 1220 .
FIG. 13 illustrates control region segment and control resource block configuration. In the example of FIG. 13 , a control region segment comprises control resource blocks for eight control beams from CB 0 to CB 7 . The control region segment can occupy any time-frequency resource blocks hardware allows for each CB. The different CBs can occupy the resource blocks in Time Division Multiplexed (TDM), in Frequency Division Multiplexed (FDM), in Code Division Multiplexed (CDM), in Spatial Division Multiplexed (SPD), or in any combination or mixture of the above multiplexing schemes.
FIG. 14 illustrates a preferred embodiment of DL and UL control resource block configuration. The configurations for DL control region segment and UL control region segment need not to be the same. In the example of FIG. 14 , there are eight DL/UL control resource blocks for eight control beams CB 0 to CB 7 in a control cycle of a cell. In one DL control region segment, the DL control resource blocks for different control beams are preferably Time Division Multiplexed (TDM) and contiguous in time. As depicted by block 1410 , the DL control resource blocks for CB 0 to CB 7 are multiplexed in time domain. Each control beam transmits at maximum power to reach maximum range. On the other hand, in one UL control region segment, the UL control resource blocks for different control beams are preferably Spatial Division Multiplexed (SDM) in conjunction with other multiplexing schemes when a base station is equipped with multiple RF chains. As depicted by block 1420 , the UL control resource blocks for CB 0 to CB 7 are multiplexed in spatial domain and in time domain. The base station equipped with multiple RF chains can receive multiple beams at the same time, and baseband digital processing can further mitigate inter-beam interference.
FIG. 15 illustrates an UL receiver having two RF chains for receiving two control beams simultaneously. In the example of FIG. 15 , a base station is equipped with an RF receiver having two RF chains RF 0 and RF 1 . In UL transmission, the base station receives CB 1 and CB 5 at the same time via RF 0 and RF 1 , and then processes the received signal using a digital baseband processing module 1510 to mitigate inter-beam interference.
FIG. 16A illustrates embodiments with and without interleaved DL/UL control resource configuration. In the top diagram of FIG. 16A , a control cycle comprises one DL control region segment 1610 and one corresponding UL control region segment 1620 . DL control region segment 1610 comprises DL control resource blocks for four control beams CB 0 to CB 3 . The DL control resource blocks for the four different control beams are TDMed and contiguous in time. Similarly, UL control region segment 1620 comprises UL control resource blocks for four control beams CB 0 to CB 3 . The UL control resource blocks for the four different control beams are TDMed and contiguous in time. In the bottom diagram of FIG. 16A , a control cycle comprises one DL control region segment 1630 and one corresponding UL control region segment 1640 . DL control region segment 1630 comprises DL control resource blocks for four control beams CB 0 to CB 3 . UL control region segment 1640 comprises UL control resource blocks for four control beams CB 0 to CB 3 . The DL control resource blocks and the UL control resource blocks for the four different control beams are TDMed but not contiguous in time. In a special case, the DL and UL control resource blocks are interleaved and alternate in time.
FIG. 16B illustrates one embodiment of control resource configuration with different DL/UL duty cycles. In the top diagram of FIG. 16B , a control cycle comprises one DL control region segment 1650 and one corresponding UL control region segment 1660 . DL control region segment 1650 comprises DL control resources for four control beams CB 0 to CB 3 , which are TDMed and contiguous in time. Each DL control beam appear twice in the control cycle. UL control region segment 1660 comprises UL control resources for four control beams CB 0 to CB 3 , which are TDMed and not contiguous in time. Each UL control beam appear once in the control cycle. As a result, the DL control beams have a shorter duty cycle than the UL control beams. In the bottom diagram of FIG. 16B , a control cycle comprises one DL control region segment 1670 and one corresponding UL control region segment 1680 . DL control region segment 1670 comprises DL control resources for four control beams CB 0 to CB 3 . UL control region segment 1680 comprises UL control resources for four control beams CB 0 to CB 3 . The DL control resource blocks and the UL control resource blocks for the four different control beams are TDMed but not contiguous in time. In a special case, every two DL control resource blocks are interleaved by one UL control resource block. As a result, the DL control beams have a shorter duty cycle than the UL control beams.
FIG. 17 illustrates embodiments of control cycles for different cells. In the top diagram of FIG. 17 , the control cycles for different cells are the same, e.g., cell-synchronous. The DL control region segments for cell 1 , cell 2 , and cell 3 are time-aligned. With cell-synchronous configuration, a UE is able to perform measurements for control beams from different cells during the same control region segment interval. In the bottom diagram of FIG. 17 , the control cycles for different cells are different, e.g., cell-non-synchronous. The DL control region segments for cell 1 , cell 2 , and cell 3 are not time-aligned. With cell-non-synchronous configuration, there is no inter-cell interference between control beams from different cells.
FIG. 18 illustrates embodiments of control cycles in TDD and FDD systems. In the top diagram of FIG. 18 , the DL control region segments and the UL control region segments are interleaved in time in TDD or FDD mode. In the bottom diagram of FIG. 18 , the DL control region segments and the UL control region segments may overlap or aligned in time in FDD mode.
Additional control resource blocks may be configured when the preconfigured resources for control beams are insufficient. For DL control beams, additional DL control resource blocks may be dynamically configured, pre-configured, or implicitly delivered from control beam identification. The addition DL control resource blocks may have a different frame format, e.g., pilot signal is not modulated because it does not need to carry beam ID. For UL control beams, additional UL control resource blocks may be dynamically configured, pre-configured, or implicitly delivered from control beam identification. The additional UL control resource blocks may be allocated for contention based or granted to a designated set of UEs. The additional UL control resource blocks may have a different frame format, e.g., pilot signal is not modulated because it does not need to carry UE ID.
FIG. 19 illustrates a control signaling procedure between a UE 1901 and a BS 1902 in a beamforming system in accordance with one novel aspect. In step 1910 , UE 1901 tries to establish a connection with BS 1902 . UE 1901 waits and detects BS control beam transmission, which are transmitted repeatedly and indefinitely. UE 1901 attempts to achieve time, frequency, and spatial synchronization with BS 1902 , and acquiring required broadcast information for accessing the network. In step 1920 , UE 1901 receives and detects control beam transmissions from BS 1902 . For example, UE 1902 receives and detects four control beam transmissions of CB# 1 to CB# 4 from BS 1902 . In step 1930 , UE 1901 selects a control beam, e.g., control beam CB# 2 for establishing connection with BS 1902 . UE 1901 first performs time and frequency synchronization with BS 1902 . Spatial synchronization is achieved after the UE selects the control beam for establishing the connection with the BS. UE 1901 then determines the UL control resources corresponding to the selected control beam CB# 2 . Moderate array gain is provided via the control beam, which partially compensates severe pathloss in mmWave channel and thus facilitates detection operation at UE. In step 1940 , UE 1901 performs random access (RA) on the UL control resources corresponding to the selected control beam CB# 2 for carrying essential information to BS 1902 that is required for connection establishment. Via the random access, the BS is aware of which control beam is preferred by the UE. The BS can reach the UE for completing the connection establishment procedure by using the selected control beam. Moderate array gain is provided via the control beam that facilitates BS reception of UE random access. The UL control resources include dedicated resource for random access and thus provide a better-protected UL channel.
FIG. 20 is a flow chart of a method of control signaling from base station perspective in a beamforming system in accordance with one novel aspect. In step 2001 , a base station allocates a first sets of DL control resource blocks for DL transmission to a plurality of user equipments (UEs) in a beamforming network. Each set of DL control resource blocks is associated with a corresponding set of beamforming weights. In step 2002 , the base station allocates a second sets of UL control resource blocks for UL transmission from the UEs. Each set of UL control resource blocks is associated with the same corresponding set of beamforming weights. In step 2003 , the base station transmits cell and beam identification information using a set of control beams. Each control beam comprises a set of DL control resource block, a set of UL control resource block, and the corresponding set of beamforming weights. A collection of the beamforming weights of the set of control beams create a radiation pattern that covers an entire service area of a cell.
FIG. 21 is a flow chart of a method of control signaling from user equipment perspective in a beamforming system in accordance with one novel aspect. In step 2101 , a user equipment (UE) receives control beam transmission from a base station using a set of control beams in a beamforming network. Each control beam comprises a set of DL control resource blocks, a set of UL control resource blocks, and an associated set of beamforming weights. In step 2102 , the UE selects a control beam for establishing a connection with the base station. In step 2103 , the UE performs random access with the base station using the selected control beam.
Pilot Signals in the Control Beams
FIG. 22 illustrates one example of pilot signals in a control beam in a beamforming system in accordance with one novel aspect. As illustrated earlier with respect to FIG. 1 , for control signaling purpose, a set of coarse TX/RX control beams are provisioned by the base station in the cellular system. The set of control beams may be periodically configured or occur indefinitely and repeatedly in order to be known to the UEs. The set of control beams covers the entire cell coverage area with moderate beamforming gain. Each control beam broadcasts a minimum amount of beam-specific information similar to Master Information Block or System Information Block (MIB or SIB) in LTE. Each beam may also carry UE-specific control and/or data traffic. Each control beam transmits a set of known pilot signals for the purpose of initial time-frequency synchronization, identification of the control beam that transmits the pilot signals, and measurement of radio channel quality for the control beam that transmits the pilot signals.
In the example of FIG. 22 , a cell of a base station is covered by eight control beams CB 0 to CB 7 . Each control beam comprises a set of downlink resource blocks, a set of uplink resource blocks, and a set of associated beamforming weights with moderate beamforming gain. Different control beams are time division multiplexed (TDM) in time domain. For example, a downlink subframe 2201 has eight DL control beams occupying a total of 0.38 msec. An uplink subframe (not shown) also has eight UL control beams occupying a total of 0.38 msec. The interval (a control cycle) between two DL/UL subframes is 5 msec. The set of control beams are lower-level control beams that provide low rate control signaling to facilitate high rate data communication on higher-level data beams. More specifically, a set of pilot signals for each of the control beams is transmitted in each of the periodically configured time-frequency resource blocks to facilitate the receiving devices to detect, identify, and synchronize to the control beams and perform the subsequent high rate data communication.
FIG. 23 illustrates a detailed example of pilot structures in control beams in a beamforming OFDM system. The interval (a control cycle) between two DL subframes in FIG. 23 is 5 msec, which contains 840 DL OFDM symbols. Each DL control region contains 128 OFDM symbols, and each control beam (e.g., CB 0 ) within each control region contains 16 OFDM symbols. For CB 0 , each resource block (e.g., resource block 2301 ) allocated for CB 0 contains L=4 OFDM symbols along time domain and a certain number of subcarriers along frequency domain depending on system bandwidth and configuration.
Within each OFDM symbol, pilot symbols are inserted once every K=8 subcarriers (or resource elements) for Rmax=320 times in one OFDM symbol (e.g., OFDM symbol 2311 ). The remaining subcarriers (or resource elements) are for data symbols. The pilot symbols have a power-boosting factor with respect to the data symbols. The pilot symbols have an offset ν m with respect to the 0-th subcarrier. The pilot symbols span a sub-band or the entire band (K*Rmax≦N fft ). The R resource elements in OFDM symbol 2311 are modulated by a signature sequence s m [n] to identify the control beam (CB 0 ). The same OFDM symbol is repeated for L times, e.g., for every OFDM symbols in resource block 2301 , forming one pilot structure. Similar pilot structures are repeated for M times, indexed by repetition index m=0, 1 . . . , M−1. For example, pilot structure 2323 have a repetition index of m=2. The M pilot structures (M repetitions) together form the pilot part of CB 0 .
The M pilot structures have a similar structure but with a different offset ν m and/or a different signature sequence s m . The actual value of offset ν m and signature sequence s m are based on the repetition index m. Potentially, the different offsets ν m resulting in a hopping pattern, while the different sequences s m are generated from circular delay-Doppler shifts of a base sequence. In one example, the different sequences s m belong to a set of Zadoff-Chu sequences with different delays and chirping slopes. As a result, the R resource elements in one OFDM symbol modulated by the signature sequence s m [n] can be used to identify a specific control beam.
FIG. 24 illustrates control beam identification based on pilot signals in a beamforming network 2400 . Beamforming network 2400 comprises a plurality of cells. Each base station configures a set of control beams to create a radiation pattern covering an entire service area of a cell for pilot signal transmission. Each control beam of the cell is identified by the pilot symbols having a hopping pattern ν m and a sequence s m [n]. Specifically, for the j-th control beam of the i-th cell, there is a corresponding identifier pair ν m (i,j) and s m (i,j)[n] with some variations.
In the example of FIG. 24 , there are nine cells (cell 0 to cell 8 ), and each cell has eight control beams (CB 0 to CB 7 ). In one example, the same hopping pattern but different sequences are associated with different control beams of the same cell. In another example, the same sequence but different hopping patterns are associated with different control beams of the same cell. In yet another example, sequences for different control beams in the same cell belong to a set of sequences derived from the same base sequence. Note that the same identifier pair may be reused spatially.
FIG. 25 illustrates variations of pilot structures with additional OFDM symbols. As depicted by the left diagram in FIG. 25 , each resource blocks allocated for a control beam contains six OFDM symbols along time domain. The left most and the right most OFDM symbols are allocated for data part, while part of the middle L=4 OFDM symbols are allocated for pilot part. Pilot symbols are inserted every K=8 subcarriers in each of the L=4 OFDM symbols and the same OFDM symbol is repeated for L=4 times. As depicted by the right diagram in FIG. 25 , each resource blocks allocated for a control beam contains four OFDM symbols along time domain. The left most and the right most OFDM symbols are allocated for data part, while part of the middle L=2 OFDM symbols are allocated for pilot part. Pilot symbols are inserted every K=8 subcarriers in each of the L=2 OFDM symbols and the same OFDM symbol is repeated for L=2 times. In other words, L is configurable by the base station and additional OFDM symbols can be padded before and/or after the pilot symbols to carry additional data symbols.
FIG. 26 illustrates variations of pilot structures with guard time. As illustrated in FIG. 26 , between switching from one control beam to another control beam, additional guard time can be inserted. For example, a guard interval is inserted between CB 0 and CB 1 to ensure that distinct transmissions for CB 0 and CB 1 do not interfere with one another.
FIG. 27 is a flow chart of a method of allocating resources for pilot symbol transmission in a beamforming system in accordance with one novel aspect. In step 2701 , a base station allocates a set of control resource blocks in a beamforming OFDM network. The set of control resource blocks comprises periodically allocated time-frequency resource blocks associated with a set of beamforming weights to form a control beam. In step 2702 , the base station partitions each resource block into a pilot part and a data part. Each pilot part is divided into M pilot structures and each pilot structure comprises L OFDM symbols. Pilot symbols are inserted once every K subcarriers for R times in each of the L OFDM symbol to form the pilot part while data symbols are inserted in the remaining resource elements to form the data part. The variables M, L, K, and R are all positive integers. In step 2703 , the base station transmits the pilot symbols and the data symbols via the control beam to a plurality of user equipments (UEs). The M pilot structures have a similar structure with a different offset ν m and a different sequence s m . Each control beam of a cell is identified by the pilot symbols having a hopping pattern based on ν m and a signature sequence s m . Specifically, for the j-th control beam of the i-th cell, there is a corresponding identifier pair ν m (i,j) and s m (i,j)[n].
Variable Cyclic Prefix
As illustrated earlier with respect to FIG. 23 , pilot symbols are inserted once every K subcarriers (or resource elements) for Rmax=320 times in one OFDM symbol of each pilot structure. In order to facilitate pilot detection for the receiving device, the pilot symbols have a power-boosting factor with respect to the data symbols. In addition, the pilot symbols are repeated for L times in each pilot structure. The L repetitions can be implemented in different ways.
FIG. 28 illustrates different embodiments of OFDM symbols with L repetitions in time domain. In the top diagram 2810 of FIG. 28 , the L repetitions are implemented in a traditional way using L OFDM symbols. That is, the resource elements (once every K subcarriers) in one OFDM symbol are modulated by a signature sequence s m [n] of the pilot signal. The same OFDM symbol is repeated for L times forming one pilot structure. Diagram 2810 illustrates a time domain representation of the L=4 OFDM symbols after performing IFFT with a normal FFT size of N fft and each OFDM symbol has a normal CP length of Ncp. In one example, N fft =1024, and the N CP =128.
In the bottom diagram 2820 of FIG. 28 , the L repetitions are implemented using one long OFDM symbol with longer FFT size CP length. That is, the resource elements (once every L*K subcarriers) in one long OFDM symbol are modulated by a signature sequence s m [n] of the pilot signal. Diagram 2820 illustrates a time domain representation of the long OFDM symbol after performing IFFT with a FFT size of L*N fft and the OFDM symbol has a CP length of L*Ncp. In one example, L*N fft =4096, and L*N CP =512. With long FFT size and long CP length, the same pilot symbols are repeated L times with phase continuity across the L repetitions in the long OFDM symbol. Note that if normal size FFT is performed on the original OFDM boundary, then phase shift rotation is needed on the pilot symbols to implement the bottom diagram 2820 .
FIG. 29 illustrates pilot structures with variable cyclic prefix length and variable length FFT. At the transmitting side 2901 , a pilot signal is first converted by a serial to parallel converter, pilot symbols are inserted to a resource block of a control beam and converted from frequency domain signal to time domain signal by applying IFFT, and then added with cyclic prefix before control beam transmission. At the receiving side 2902 , the receiver operates on the received time domain signal by performing FFT to reconstruct the pilot structure. The cyclic prefix is first removed from the received signal, then converted from time domain signal back to frequency domain signal by applying FFT, and converted by a parallel to serial converter. Pilot symbols are extracted to recover the pilot signal.
Diagram 2910 of FIG. 29 is a frequency domain representation for pilot structure with index m=0, and diagram 2930 is a corresponding time domain representation of the OFDM symbols for pilot structure with index m=0. As shown in diagram 2910 , pilot symbols are inserted once every K=8 subcarriers for the first OFDM symbol. The same OFDM symbol is then repeated for the second OFDM symbol. As shown in diagram 2930 , the first two OFDM symbols are applied with FFT size of N fft with a CP length of N CP . Starting from the next OFDM symbol in the same pilot structure m=0, pilot symbols are inserted once every K=2*8=16 subcarriers as depicted by 2910 . The third OFDM symbol is applied with FFT size of 2*N fft with a CP length of 2*N CP as depicted by 2930 . Similarly, diagram 2920 of FIG. 29 is a frequency domain representation for pilot structure with index m=1, and diagram 2940 is a corresponding time domain representation of the OFDM symbol for pilot structure with index m=0. As shown in diagram 2920 , pilot symbols are inserted once every K=4*8=32 subcarriers for the OFDM symbol. As shown in diagram 2940 , the OFDM symbol is applied with FFT size of 4*N fft with a CP length of 4*N CP .
In beamforming networks, the delay spread is larger for wider beam because of more multi-paths in the channel and results in greater chance to pull in paths with longer delays. Some UEs may choose to use wider RX beam to search for control beams, and thus have longer delay spreads in the received signal. Some UEs may not even support beamforming. Longer delay spread needs longer CP length. With certain control beam resource blocks configured to support variable-length FFT with variable-length CP length in different pilot structures, UEs with larger delay spread can received their control data using longer FFT size and longer CP length. Note that the pilot symbols remain unchanged across the L repetitions. Therefore, pilot symbols are always processed at the largest FFT size (e.g., L*N fft ), or at its equivalent regular FFT size (e.g., N fft ) with appropriate phase rotations/shifts. Furthermore, constant power is maintained for the pilot symbols across the L repetitions.
FIG. 30 is a flow chart of supporting variable CP length for pilot signal transmission in a beamforming network in accordance with one novel aspect. In step 3001 , a base station allocates time-frequency resource blocks in a beamforming OFDM network for control beam (CB) transmission. In step 3002 , the base station partitions each resource block into a pilot part and a data part. The pilot part comprises M pilot structures and each pilot structure comprises a number of OFDM symbols in time domain and a number of subcarriers in frequency domain. In step 3003 , the base station inserts pilot symbols of a pilot signal in each OFDM symbol in the pilot part. The pilot symbols are repeated for L times in each pilot structure, and each pilot structure is applied by one or more Inverse Fast Fourier Transfers (IFFTs) with corresponding one or more variable cyclic prefix (CP) lengths for CB transmission. M and L are positive integers. In one embodiment, a pilot structure comprises L OFDM symbols, the L repetitions are implemented by an IFFT of length N fft for L times, and each OFDM symbol has a cyclic prefix (CP) length of N CP . In another embodiment, a pilot structure comprises one OFDM symbol, the L repetitions are implemented by an IFFT of length (L×N fft ), and the OFDM symbol has a cyclic prefix (CP) length of (L×N CP ).
FIG. 31 is a flow chart of supporting variable CP length for pilot signal reception in a beamforming network in accordance with one novel aspect. In step 3101 , a user equipment (UE) receives control beam transmission from a base station in a beamforming OFDM network. The UE receives a time domain signal from pilot symbols that are transmitted over periodically allocated time-frequency resource blocks of a control beam. In step 3102 , the UE processes the time domain signal by removing one or more cyclic prefixes (CPs) with a variable CP length and performing corresponding one or more variable-length Fast Fourier Transfers (FFTs) to reconstruct a pilot part of a resource block, wherein the pilot part comprises M pilot structures and each pilot structure comprises a number of OFDM symbols in time domain and a number of subcarriers in frequency domain. In step 3103 , the UE extracts the pilot symbols from each pilot structure. The pilot symbols are repeated for L times in each pilot structure, and M and L are positive integers. In one embodiment, a pilot structure comprises L OFDM symbols, the UE extracts the L repetitions by performing an IFFT of length N fft for L times, and each OFDM symbol has a cyclic prefix (CP) length of N CP . In another embodiment, a pilot structure comprises one OFDM symbol, the UE extracts the L repetitions by performing an IFFT of length (L×N fft ), and the OFDM symbol has a cyclic prefix (CP) length of (L×N CP ).
Detection Procedure
FIG. 32 illustrates a three-stage pilot signal detection procedure in accordance with one novel aspect. As illustrated earlier with respect to FIG. 23 , pilot signals are transmitted via control beams in a cell using periodically allocated radio resource blocks. For DL pilot transmission, a base station allocates radio resource blocks (e.g., resource block 3210 ) and insert pilot symbols onto each pilot structure (e.g., pilot structure 3220 ). Within each OFDM symbol, pilot symbols are inserted once every K=8 subcarriers (or resource elements) for Rmax=320 times in one OFDM symbol. The pilot symbols have a power-boosting factor with respect to the data symbols. The pilot symbols have an offset ν m with respect to the 0-th subcarrier. The pilot symbols span a sub-band or the entire band (K×Rmax≦N fft ). The R resource elements in each OFDM symbol are modulated by a signature sequence s m [n] to identify a control beam. The same OFDM symbol is repeated for L times, e.g., for every OFDM symbols in the resource block, forming one pilot structure. Similar pilot structures are repeated for M times, indexed by repetition index m=0, 1 . . . M−1.
The pilot signal for (cell i, control beam CB j) can be represented by:
p ( i , j ) ( t ) = ∑ m = 0 M - 1 s m ( i , j ) ( t - mLT 0 ) ⅇ j2π v m ( i , j ) f s ( t - mLT 0 )
Where
s m (i,j) (t) is the time domain equivalent of the pilot signal for the j-th control beam of the i-th cell in the m-th repetition. L is the number of OFDM symbols in each pilot structure. m=0 . . . M−1 is the repetition index of each pilot structure. ν m (i,j) is the offset with respect to the 0-th subcarrier. T 0 is the regular OFDM symbol length (Ts) plus the regular CP length T CP .
The received signal at the UE through delay-Doppler channel can be represented by:
r ( t ) = ∑ i , j ∫ p ( i , j ) ( t - τ ) ⅇ j2π vt · h ( i , j ) ( τ , v ) ⅆ τ ⅆ v
Where
p (i,j) is the pilot signal for the j-th control beam in the i-th cell. h (i,j) is the channel response for the j-th control beam in the i-th cell.
Based on the received signal r(t) from the control beam transmission, the receiving device (UE) needs to detect the presence of the pilot signal, e.g., identify the (cell, CB) ID and achieve time-frequency synchronization based on r(t). An exemplary three-stage pilot detection approach with reduced complexity is proposed. In stage-1 detection (step 3201 ), the UE detects the presence of control beams and performs coarse time-frequency offset estimation. In stage-2 detection (step 3202 ), the UE detects control beam resource boundaries. In stage-3 detection, the UE first performs signature sequence correlation and beam identification (step 3203 ), and then performs fine time-frequency synchronization and channel estimation (step 3204 ).
FIG. 33 illustrates a stage-1 control beam detection and coarse time-frequency estimation. A stage-1 detection detects presence of any control beam and its coarse resource block boundary and estimates the coarse time and carrier frequency offset. The detector calculates the sliding DFT of the extended OFDM symbols (the sliding windows may or may not overlap). Energy is summed over sub-carriers in which pilot symbols are inserted for each hypothesized frequency offset.
As illustrated in FIG. 33 , UE receives a time-domain signal, which is carried by L*N samples in each pilot structure. The received time-domain signal is then converted to a frequency domain signal via Discrete Fourier Transfer (DFT). At each time instance t, potential pilot symbols are extracted once every K*L subcarriers (e.g., resource elements or tones) from a total of L*N subcarriers with an offset i. The receiver applies a sliding DFT plus combining algorithm in detecting the presence of any control beam and pilot symbols based on energy detection. In other words, the amplitude (energy) of the potential pilot tones are summed up for time instance t and offset i, and the receiver chooses the best (t,i) such that the amplitude reaches the maximum. More specifically, at time instance t and offset i=0 . . . (KL−1), the amplitude summation of pilot tones can be represented by:
Amp t 0 ,0=Σ|·| 2 , Amp t 0 ,KL− 1=Σ|·| 2 (for time t 0)
Amp t n ,0=Σ|·| 2 , Amp t n ,KL− 1=Σ|·| 2 (for time t 0)
Once the time and frequency index (t,i) is chosen, then the receiver determines that the coarse central frequency CFO=i*(1/KL), and the coarse OFDM boundary is at time t. Note that if the pilot tones have a power boosting as compared to data tones, the energy detection method may be more accurate.
FIG. 34 illustrates a stage-2 control beam reference block boundary detection. A Stage-2 detector detects the coarse boundary (up to a window of uncertainty) of the control beam resource block boundary detected in stage-1 after the correction of frequency offset estimated in stage-1. Stage-2 detection is similar to stage-1 with the uncertainty in frequency offset removed, potentially longer extended OFDM symbols, and finer sliding window resolution. During the stage-2 energy detection, the presence of more control beams and their finer time-frequency synchronization can be achieved. The receiver applies a simple sliding DFT with energy detection of coherently accumulated pilot symbols after coarse CFO correction. The receiver is then able to determine a small fraction of OFDM symbol and sub-carrier for finer time-frequency synchronization.
When the pilot symbols are inserted every K sub-carriers in an OFDM symbols, the corresponding time domain signal will be K repetitions of a certain length (N fft /K) sequence related to the complex values of the pilot symbols. Each one of those repetitions is a pilot segment. In the example of FIG. 34 , the cyclic prefix is of length N fft /K. Therefore, there are K+1 pilot segments in each OFDM symbol including its cyclic prefix. Because there are L repetitions in a pilot structure, there are a total of (K+1)*L pilot segments. At each time instance, all samples of the pilot segments are summed up to output an absolute accumulation (energy), e.g., AccOutt 0 for time instance t 0 , and AccOutt 1 for time instance t 1 , and so on so forth. For example, at time t 1 , the accumulation of all samples of the pilot segment can be represented by AccOutt 1 =RxS 1 + . . . +RxS (K+1)*L . The receiver then choose the time instance with the maximum accumulation for time domain synchronization. The L times repetition raises detection metric for pilot symbols by 10*log 10 (L) dB. Some control data symbols may also be repeated L times to yield sufficient SNR level for cell edge UEs, and the base station can avoid false alarm by limiting such resource mapping or distributing such resource mapping randomly. Pilot power boosting with respect to data symbols further improves detection performance.
FIG. 35 illustrates a stage-3 sequence correlation and beam identification and finest time-frequency synchronization. From the outcome of the stage-2 detection, a search interval is determined, which is in the order of the cyclic prefix length. During a search interval, all the pilot segments are summed up by the receiver: RxS=RxS 1 + . . . +RxS (K+1)*L . The receiver then correlates the received signal RxS with all possible pilot sequences p(i,j) for all i and j. Control beam j in cell i is detected if it has the maximum correlation out in the search interval. Finest time and frequency synchronization is then performed. For example, once the strongest sequence and its associated control beam are detected, the stage-3 process in FIG. 35 can be performed for that particular sequence over finer hypotheses of the time and frequency offset interval to achieve the finest time and frequency synchronization.
FIG. 36 is a flow chart of a method of pilot signal detection based on control beam transmission in a beamforming network in accordance with one novel aspect. In step 3601 , a user equipment (UE) receives control beam transmissions from a base station in a beamforming OFDM network. A pilot signal is transmitted over periodically allocated time-frequency resource blocks of a control beam in a cell. In step 3602 , the UE processes pilot symbols carried in a pilot part of a resource block, the pilot part comprises M pilot structures and each pilot structure comprises L OFDM symbols in time domain and R subcarriers in frequency domain. The pilot symbols are inserted once every K subcarriers for R times in each OFDM symbol, and M, L, R, and K are positive integers. In step 3603 , the UE detects the control beam and the pilot signal based on the control beam transmission.
In one embodiment, a three-stage pilot detection procedure is performed. In stage-1, the UE detects an existence of the control beam by performing a sliding Discrete Fourier Transform (DFT) and thereby estimating a coarse time-frequency offset. It involves energy detection by selecting a time instance and a frequency offset to achieve a maximum combined energy. In stage-2, the UE detects a time-frequency resource block boundary of the control beam. In involves performing a sliding DFT with energy detection of accumulated pilot symbols of a fraction of OFDM symbols and sub-carriers. In stage-3, the UE detects the pilot signal and identifying the control beam and performing fine time-frequency synchronization and channel estimation. It involves sequence correlation with all possible pilot sequences. The detected control beam has a maximum correlation during a search interval determined by the stage-2 detection.
Although the present invention has been described in connection with certain specific embodiments for instructional purposes, the present invention is not limited thereto. Accordingly, various modifications, adaptations, and combinations of various features of the described embodiments can be practiced without departing from the scope of the invention as set forth in the claims. | A beamforming system synchronization architecture is proposed to allow a receiving device to synchronize to a transmitting device in time, frequency, and spatial domain in the most challenging situation with very high pathloss. A detector at the receiving device detects the presence of control beams, synchronizes to the transmission and estimates the channel response by receiving pilot signals. The detector has low complexity when exploiting the structure of the pilot signals. The detector consists of three stages that break down the synchronization procedure into less complicated steps. The detector accurately estimates the parameters required for identifying the transmit device and performing subsequent data communication. | 7 |
The present invention concerns communication systems which, in order to improve the fidelity of the transmission, the data to be transmitted are subjected to a channel coding.
It should be stated that the so-called “channel” coding consists of introducing a certain redundancy into the data to be transmitted. At the receiver, the associated decoding method then judiciously uses this redundancy for detecting any transmission errors and if possible correcting them.
Some of these decoding methods are “iterative”. This type of decoding (parallel turbocode, block turbocode, serial convolutional code and so on) is characterised by the fact that the reliability of the decoded data (in the sense of their identity with the data before coding) increases with the number of iterations. It is therefore necessary to adjust this number of iterations so as to obtain sufficient transmission quality.
Various algorithms producing a criterion for stopping the iterative decoding can be proposed. The most simple use code words formed by adding to the data words a certain number of bits known to the decoder in advance; these additional bits serve as a reference for the decoder in order to determine how many iterations are necessary for correcting the transmission errors in accordance with the bit error rate aimed at.
So-called “adaptive” algorithms have also been proposed for determining the appropriate number of iterations, that is to say algorithms in which the number of iterations is determined dynamically by the reception device, according to an intrinsic estimation of the reliability of the data received. For example, the description of such an adaptive algorithm, based on the measurement of the entropy of the signals received, can be found in the article by M. MOHER entitled “Decoding via Cross-Entropy Minimisation”, pages 809 to 813 of the transactions of “Globecom '93, IEEE Global Telecommunications Conference”, vol. 2, Houston, Tex., USA (published by IEEE, Piscataway, N.J., USA, 1993); another adaptive algorithm, also based on measurements of entropy, is known from U.S. Pat. No. 5,761,248. Yet another example of an adaptive algorithm, based in this case on a measurement of the noise variance, is described in the article by P. ROBERTSON entitled “Illuminating the Structure of Coder and Decoder for Parallel Concatenated Recursive Systematic (Turbo) Codes” presented at “Globecom '94” (published by IEEE, Piscataway, N.J., USA, 1994). These “adaptive” algorithms thus make it possible to dispense with the transmission of additional bits independent of the data, but at the cost of appreciably increased complexity.
However, all the conventional algorithms have in common the fact that they take no account of the fact that, in many practical situations, the data transmitted do not all, burst after burst, have the same importance with regard to their impact on the clarity of the message. These conventional coding/decoding methods therefore use a larger number of iterations than necessary with regard to the data of lesser importance, for which it is possible to tolerate an error rate greater than the maximum rate tolerable for the more important data.
In order to remedy this drawback, the present invention proposes a novel transmission and decoding algorithm, which can be designated as an “adaptive on transmission” algorithm, in contradistinction to “adaptive on reception” decoding algorithms which, as has been seen, determine the desirable number of iterations by examining the received signal.
This is because the present invention concerns, according to a first of its aspects, on the one hand, a method of transmitting blocks of data which have been coded by means of a channel coding method compatible with an iterative decoding, said method being remarkable in that, for at least one of said blocks of data, at least one parameter associated with this block of data is transmitted, said parameter indicating the minimum number of iterations to be applied by an iterative coder during the decoding of the block of data associated with this parameter.
In addition, according to this first aspect of the invention, the latter concerns, correlatively, a method of decoding blocks of data which have been coded by means of a channel coding method compatible with an iterative decoding, said method being remarkable in that, a signal containing at least one parameter associated with a block of data having been transmitted for at least one of these blocks of data,
said parameter is extracted from the signal containing it, and said parameter is used as an indicator of the minimum number of iterations applied by the iterative decoder to the block of data associated with its parameter.
Thus the methods according to the invention make it possible to choose the desirable number of iterations of the decoder according, amongst other things (or exclusively), to the nature of the signal before it is transmitted.
It is possible to imagine various criteria leading to the choice of the desirable number of iterations for each block of data transmitted. For example, a very simple criterion consists of choosing a minimum number of iterations which is invariable for all the blocks of data forming part of the same message, if it is considered that this number of iterations will always be sufficient, having regard to the signal to noise ratio of the channel, in order to ensure an acceptable rate. However, the invention proves to be particularly advantageous in the case where there is a certain hierarchy with regard to the reliability required for the transmission of these blocks of data, this concept of decoding quality which is tuneable according to some given hierarchy between the data to be transmitted being also applicable to types of decoding other than iterative decoding.
A transmission method which takes into account such a hierarchy can be found in EP-0 926 116 (based on JP-36883997). According to this method, channel coding is realized by means of a unit which adds parity bits to the data, the number of these parity bits being a function of the relative importance of these data, so that the parameters of the coding as well as the parameters of the decoding depend on the data hierarchy. Thus, the parameters of the channel coding method used are made to vary within the same message. Because of this, implementing the transmission method according to EP-0 926 116 is fairly cumbersome.
According therefore to a second aspect of the present invention, the matter concerns, on the one hand, a method of transmitting blocks of data, in which, for at least one of said blocks of data, at least one parameter associated with this block of data is transmitted, said parameter representing the relative importance of the block of data associated with this parameter within the message transmitted by all the blocks of data, characterised in that the data are coded by means of a channel coding method which does not take into account said parameter.
Moreover, according to this second aspect of the invention, the latter concerns, correlatively, a method of decoding blocks of data, for which a signal containing at least one parameter associated with at least one of these blocks of data has been transmitted, said parameter representing the relative importance of the block of data associated with this parameter within the message transmitted by all the blocks of data, characterised in that the data have been coded by means of a channel coding method which does not take into account said parameter, and in that
said parameter is extracted from the signal containing it, and said parameter is used as a guide for the decoder so that data judged to be more important than others may benefit from a channel decoding of higher quality.
Thus, the methods according to the invention, besides being easy to implement, make it possible to achieve “intelligent” savings, that is to say in direct relationship with the nature of the data to be transmitted, in terms of processing time and costs, which the known methods have not made it possible to achieve up to the present time.
According to a particularly advantageous embodiment of this second aspect of the invention, the blocks of data are transmitted in order of decreasing importance and, where the parameter associated with a block of data newly received has not been able to decoded correctly, a parameter identical to the one associated with the previous block of data will be allocated to this new block of data.
Thus it will be possible to guarantee the quality of the decoding even if parameters are occasionally made indecipherable consequent upon transmission faults.
According to requirements, said parameters according to the first or second aspect of the invention can be either transmitted over the same channel as the associated data or transmitted over a separate channel.
Where the parameters according to the second aspect of the invention are transmitted over the same channel as the associated data, provision can advantageously be made, for said transmission, for a signal consisting of bursts of bits to be transmitted, each burst containing on the one hand one or more blocks of data either complete or fragmented over several successive bursts, and on the other hand the parameter associated with the most important data appearing in the following burst.
Thus the decoder receiving a burst will know what quality of decoding is applied to it since it will already have identified the corresponding parameter, following the decoding of the previous burst.
According to requirements, said parameters according to the first or second aspect of the invention can either undergo the same channel coding as the associated data or undergo a different channel coding, or undergo no channel coding at all.
It may be advantageous, notably in cases where it is predicted that the quality of the transmission may degrade progressively between the start and end of the transmission, to transmit firstly the values of parameters corresponding to all the blocks of data in the same message and secondly these blocks of data; in addition, this embodiment is compatible with the use of decoders not provided for implementing the invention, which could thus decode the blocks of data in a conventional fashion, after having purely and simply ignored the signal containing the parameters according to the invention.
According to a third of its aspects, the invention concerns various devices.
It thus concerns, firstly, a device for processing blocks of data intended to be transmitted by means of a method according to the first and/or second aspect of the invention, said device being remarkable in that it has:
means for obtaining said parameter, and means for creating a link between this parameter and the associated block of data with a view to the transmission of this parameter and this block of data.
Correlatively, the invention concerns, secondly, a device for assisting with the decoding of blocks of data which have been transmitted by means of a method according to the first and/or second aspect of the invention, said device being remarkable in that it has:
means for extracting said parameter from the signal containing it, and means for, on the basis of said parameter, assisting a decoder responsible for decoding said blocks of data.
The invention concerns, thirdly, a device for coding blocks of data, characterised in that it has:
at least one device for processing blocks of data as described succinctly above, and at least one channel coder.
Correlatively, the invention concerns, fourthly, a device for decoding blocks of data, said device being remarkable in that it has:
at least one channel decoder, and at least one device for assisting with decoding as described succinctly above.
The present invention also relates to:
an apparatus for sending coded digital signals, including a coding device according to the invention, and having means for transmitting said blocks of coded data and said parameters, an apparatus for receiving coded digital signals, including a decoding device according to the invention, and having means for receiving said blocks of coded data and said parameters, a telecommunications network, including at least one transmission apparatus or one digital signal processing apparatus according to the invention, a data storage means which can be read by a computer or microprocessor storing instructions of a computer program, making it possible to implement one of the methods succinctly disclosed above, a data storage means which is removable, partially or totally, and which can be read by a computer and/or microprocessor storing instructions of a computer program, making it possible to implement one of the methods succinctly described above, and a computer program, containing instructions such that, when said program controls a programmable data processing device, said instruction means that said data processing device implements one of the methods succinctly disclosed above.
The advantages offered by these devices, digital signal processing appliances, telecommunications networks, data storage means and computer programs are essentially the same as those offered by the methods according to the invention.
Other aspects and advantages of the invention will emerge from a reading of the following detailed description of particular embodiments, given by way of non-limitative examples. The description refers to the drawings which accompany it, in which:
FIG. 1 depicts schematically the structure of a conventional turbocoder,
FIG. 2 depicts schematically the structure of a conventional turbodecoder,
FIGS. 3 a and 3 b illustrate the general principle of coding by decomposition into sub-bands by means of a simple example of an image to be transmitted,
FIG. 4 is a block diagram of an apparatus for sending digital signals coded according to the invention using a turbocoder,
FIG. 5 a shows a first embodiment of the module 20 of FIG. 4 ,
FIG. 5 b shows a second embodiment of the module 20 of FIG. 4 ,
FIG. 6 a shows a first embodiment of the content of the signal coming out of the insertion module 30 in FIG. 4 ,
FIG. 6 b shows a second embodiment of the content of the signal coming out of the insertion module 30 in FIG. 4 ,
FIG. 7 is a flow diagram representing the main successive steps of the coding method implemented by the apparatus of FIG. 4 ,
FIG. 8 shows a preferred embodiment of the apparatus of FIG. 4 ,
FIG. 9 is a block diagram of an apparatus for receiving coded digital signals according to the invention using a turbodecoder
FIG. 10 is a flow diagram representing the main successive steps of the decoding method implemented by the apparatus of FIG. 9 ,
FIG. 11 shows a preferred embodiment of the apparatus of FIG. 9 , and
FIG. 12 depicts schematically a wireless telecommunication network able to implement the invention.
TECHNOLOGICAL BACKGROUND TO THE PREFERRED EMBODIMENT
The preferred embodiment of the invention presented above by way of example has the following characteristics:
a) the coding of the data for the purpose of transmission is effected by a turbocoder consisting of two convolutional coders and one interleaver (two-parity system), and b) decoding after reception is effected by a turbodecoder consisting of two decoders (for example of the “BJCR” type or of the “SOVA” type, two interleavers, one deinterleaver, one adder and one decision unit.
It will be recalled that a conventional turbocoder consists of two recursive systematic convolutional (RSC) coders and one interleaver, arranged as shown in FIG. 1 . The turbocoder supplies as an output three series of binary elements (x, y 1 , y 2 ), where x is the so-called systematic output of the turbocoder, that is to say one which has undergone no processing compared with the input signal, y 1 is the output coded by the first RSC coder, and y 2 is the output coded by the second RSC coder after passing through the interleaver π 1 .
FIG. 2 depicts an example of a conventional turbodecoder able to decode data supplied by a turbocoder like the one in FIG. 1 . The inputs {circumflex over (x)}, ŷ 1 , ŷ 2 of the turbodecoder are the outputs of the turbocoder as received by the decoder after passing through the transmission channel. Such a turbodecoder requires in particular two decoders, designated “decoder 1 ” and “decoder 2 ” in FIG. 2 , for example of the BCJR type, that is to say using the algorithm of Bahl, Cocke, Jelinek and Raviv, or of the SOVA type (in English: “Soft Output Viterbi Algorithm”).
A conventional turbodecoder also requires looping back of the output of the deinterleaver π 2 onto the input of the first decoder in order to transmit the so-called “extrinsic” information from the second decoder to the first decoder, and an adder 70 and a decision unit 80 .
For more details on turbocodes, reference can usefully be made to the article by C. BERROU, A. GLAVIEUX and P. THITIMAJSHIMA entitled “Near Shannon Limit Error-Correcting Coding and Decoding: Turbo-Codes”, ICC '93, Geneva (published by IEEE, Piscataway, N.J., USA, 1993), or to the article by R. DE GAUDENZI and M. LUISE entitled “Audio and Video Digital Radio Broadcasting Systems and Techniques”, pages 215 to 226 of the Proceedings of the Tirrenia Sixth International Seminar on Digital Telecommunications (1993).
In the preferred embodiments of the invention described below, the data result from the processing of images by the so-called “decomposition into sub-bands” method.
It should be stated that the “decomposition into sub-bands” method or source coding “by decomposition into sub-bands” consists of dividing each image to be transmitted into several hierarchical blocks of data (referred to as “sub-bands”), and this iteratively. For example, at the first iteration, four sub-bands are created: the first contains the low frequencies of the image, the second the horizontal high frequencies, the third the vertical high frequencies and the fourth the diagonal high frequencies. Each sub-band contains a quarter of the data (pixels) of the original image. At the second iteration, the low frequency sub-band is itself decomposed into four new blocks containing the low frequencies, the horizontal high frequencies, the vertical high frequencies and the diagonal frequencies relating to this sub-band. The decomposition process is thus continued a certain number of times according to requirements.
This method is illustrated here by way of example by the decomposition into ten sub-bands (corresponding to three resolution levels) of the image depicted in FIG. 3 a . The result is illustrated in FIG. 3 b . The level of lowest resolution (top left-hand corner in FIG. 3 b ) contains the sub-bands LL 3 , HL 3 , LH 3 and HH 3 ; the second resolution contains the sub-bands HL 2 , LH 2 and HH 2 ; the highest resolution level contains the sub-bands HL 1 (vertical high frequencies), LH 1 (horizontal high frequencies) and HH 1 (diagonal high frequencies). It should be noted that the sub-band LL 3 is merely a reduction of the original image, whilst the other sub-bands identify details of this image.
The advantage of this coding by decomposition into sub-bands results from the fact that certain blocks are more important than others with regard to the quality of the image obtained after recomposition. This is because the low frequencies contribute more to the intelligibility of the image than the high frequencies.
The method of decomposition into sub-bands also offers the possibility of allocating to each sub-band a hierarchical rank DS in relation to the importance of these data (“Data Significance”). Thus, in order to exploit this possibility, in a known manner, in the example in question, a value which is all the higher, the lower the hierarchical importance of the corresponding block of data, will be given to DS; more precisely, there will be allocated successively to the sub-band LL 3 a value of DS equal to 1, then to the sub-bands LH 3 , HL 3 and HH 3 a value of DS equal to 2, then to the sub-bands LH 2 , HL 2 and HH 2 a value DS equal to 3, and finally to the sub-bands LH 1 , HL 1 and HH 1 a value of DS equal to 4.
This example of the coding by decomposition into sub-bands (used conventionally for apportioning the compression level according to the importance of each block) illustrates the fact, essential for the invention, that there are in practice situations where the data to be transmitted lend themselves naturally to a classification in terms of their importance, which makes it possible, by virtue of the invention, namely by apportioning the quality of the channel decoding to this hierarchy, to make savings with regard to decoding and, thereby, with regard to the entire data coding/transmission/decoding process.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 4 shows, highly schematically, a digital signal transmission apparatus 48 according to the invention. The latter comprises a transmitter 45 and a coding device 47 . In this embodiment, the coding device 47 has on the one hand a turbocoder 40 and on the other hand, in accordance with the invention, a device for processing blocks of data 46 . These data come, in this embodiment, from an image processing unit (not shown) decomposing the images to be transmitted into sub-bands and allocating to each sub-band a hierarchical rank DS, as explained above.
The data coming from this image processing unit are introduced into the apparatus through an input for data to be transmitted 12 a , whilst the information of hierarchical rank DS is introduced into the apparatus through a hierarchical rank input 13 a.
In the preferred embodiment, the hierarchical rank DS is introduced, through a link 13 , into a converter 20 which transforms it into a parameter IN which, according to the invention, will serve as an indicator to the iterative decoder (see module 300 in FIG. 7 ) in order to determine the number of iterations (the “Iteration Number”) to be applied to the associated block (LL 3 , LH 3 , HL 3 , HH 3 , . . . ) as explained below with reference to FIGS. 7 and 8 .
The converter 20 consists here of a memory loaded with a look-up table (LUT) (see FIGS. 5 a and 5 b ), which can be produced in software form or in the form of a specific logic circuit.
It should be noted that the parameter IN can either be this number of iterations proper, or the bijective function, known to the decoder, of this number of iterations; in the examples considered below, IN is an increasing function of the number of iterations.
In the preferred embodiment, the signal conveying these parameters IN and the signal conveying the blocks of data (LL 3 , LH 3 , HL 3 , HH 3 , . . . ) supply, through links 25 and 12 (respectively), an insertion module 30 . This module 30 is responsible for associating the content of these two signals in a certain chosen manner; the resulting signal then enters the turbocoder 40 , which codes the data of this signal before sending the blocks of data thus obtained to the transmitter 45 .
A conversion of an item of information of the DS type into an item of information of the IN type within the converter 20 can be arranged in various ways according to the requirements and the acceptable level of complexity.
The table in FIG. 5 a shows an example of a particularly simple embodiment of this conversion, in which the value of IN is a function only of the value of DS. Naturally, IN varies inversely as DS.
It should be noted that here, as a variant, it would be possible to transmit DS rather than IN (the coder obviously being arranged accordingly), in which case it will be DS itself which will fulfil the role of parameter within the meaning of the invention; in addition, in this same case, the converter 20 in the apparatus depicted in FIG. 4 will be omitted, the means of obtaining said parameter then being reduced to the hierarchical rank input 13 a.
The table in FIG. 5 b shows an example of a more elaborate embodiment, in which the values of IN indicated in the table depend not only on DS but also on the signal to noise ratio SNR anticipated for the transmission of the corresponding data block. Naturally, for a constant DS, the noisier the channel (low SNR) the higher the number of iterations must be to obtain an acceptable bit error rate.
FIGS. 6 a and 6 b are two examples of a possible structure for the outgoing signal of the insertion module 30 of FIG. 4 . This output signal, in these examples, consists of a series of bursts, each burst n containing the value of IN attached to a sub-band contained, wholly or partially, in the following burst (n+1). In the case of FIG. 6 a , it has been possible to exactly accommodate one sub-band per burst. In the case of FIG. 6 b , two partial sub-bands per burst are transmitted. Each burst (n+1) thus comprises on the one hand the second part of a sub-band with which there is associated the value of IN contained in the burst n, and on the other hand a first part of the following sub-band, of lesser importance, which thereby benefits from the decoding of a higher number of iterations than necessary.
Thus, for the embodiments in FIGS. 6 a and 6 b , the module 30 fulfils a function known as “insertion”, consisting of putting end to end the information received on two distinct channels in accordance with a fixed synchronisation process. This module 30 can be produced in the form of software governing a memory, or in the form of a specific logic circuit.
FIG. 7 is a flow diagram representing the main successive steps of the coding method implemented by the apparatus illustrated in FIG. 4 .
After a start-up step 700 , the converter 20 receives, at step 710 , the information of hierarchical rank DS coming from the input 13 a , and converts them into parameter values IN. These values of IN are, at step 720 , received by the insertion module 30 , which also receives, at another input, the data to be transmitted, and the insertion module 30 associates the two types of information as described above. The bursts thus formed are, at step 730 , transmitted to the turbocoder 40 , which processes them with a view to transmission by the transmitter 45 . At step 740 , it is determined whether the burst which has just been processed was the last in the message: if such is the case, the process ends at step 750 ; otherwise the following burst is prepared, resuming the process at step 710 .
The block diagram in FIG. 8 depicts a preferred embodiment of the apparatus illustrated in FIG. 4 . This apparatus 48 is associated, in this embodiment, with an image processing unit (not shown).
The turbocoder 40 and the data block processing device 46 are here implemented by a logic unit associated with storage means and peripheral appliances. The coding device 47 thus comprises a calculation unit CPU (“central processing unit”) 560 , a temporary data storage means 510 (RAM memory), a data storage means 520 (ROM memory), character entry means 530 , such as a keyboard for example, image display means 540 , such as a screen for example, and input/output means 550 .
The RAM memory 510 contains notably:
a memory “data 1 — in” in which the input data supplied by the image processing unit are temporarily stored, a memory area “DS” in which the values of DS supplied by the image processing unit are temporarily stored, a memory area “IN” in which the values of IN supplied by the look-up table described with reference to FIG. 5 b (in the preferred embodiment) are temporarily stored, memory areas “x”, “y 1 ”, and “y 2 ” in which the series of bits x, y 1 , y 2 supplied by the turbocoder 40 are temporarily stored, and a memory area “data 1 — out” in which the output data obtained at the end of the coding method according to the invention are temporarily stored.
The ROM memory 520 contains:
a memory area “P 1 ” in which there is recorded a program implementing a coding method according to the invention, and a memory area “LUT” in which the look-up table mentioned above is recorded.
FIG. 9 shows, highly schematically, a digital signal reception apparatus 333 according to the invention. The latter comprises a receiver 60 and a decoding device 332 . In this embodiment, the decoding device 332 has, on the one hand, a turbodecoder 300 and on the other hand, according to the invention, a device for assisting with decoding 331 . The turbodecoder 300 receives on the one hand coded data coming from the receiver 60 and on the other hand the corresponding successive values of IN coming from a delay device 320 responsible for storing each value of IN whilst awaiting the arrival of the corresponding burst. The decoding product effected by the turbodecoder 300 is examined by a module 310 responsible for extracting therefrom the value of IN necessary for decoding the data contained in the following burst. The remainder of the signal coming out of the decoder 300 , which contains the data of the message proper (that is to say, in this embodiment, the sub-bands), ends up at an interface 65 a connected to a unit (not shown) here responsible for reconstructing the initial image from these sub-bands.
FIG. 10 is a flow diagram representing the successive main steps of the decoding method implemented by the apparatus illustrated in FIG. 9 .
After the starting up 400 of the decoding of a new message, the turbocoder 300 , at step 410 , is supplied with an initial value INmax of IN chosen in advance, sufficiently great to ensure a decoding of the first burst with sufficient quality in all circumstances. At step 420 , the decoder 300 effects the decoding whilst being guided by the last value of IN supplied by the delay device 320 . The product of this decoding is examined at step 430 by the module 310 , which extracts therefrom the value of IN necessary for decoding the data contained in the following burst.
Moreover, at step 440 it is determined whether the burst received was the last burst in the message. If such is the case, the decoding ends at step 450 ; otherwise there is a wait until the receiver 60 receives the following burst, and the process is resumed at step 420 using the value of IN issuing from the delay device 320 .
The block diagram in FIG. 11 shows a preferred embodiment of the apparatus illustrated in FIG. 9 . This apparatus 333 is associated, in this embodiment, with an image reconstruction unit (not shown).
The turbodecoder 300 and the device assisting with decoding 331 are here implemented by a logic unit associated with a storage means and peripheral appliances. The decoding device 332 thus comprises a calculation unit CPU 660 , a temporary data storage means 610 (RAM memory), a data storage means 620 (ROM memory), character entry means 630 , image display means 640 and input/output means 650 .
The RAM memory 610 contains notably:
a memory area “data 2 — in” in which the input data supplied by the receiver 60 are temporarily stored, a memory area “IN” in which the values of IN guiding the decoding are temporarily stored, the memory areas “{circumflex over (x)}”, “ŷ 1 ”, “ŷ 2 ” in which the values {circumflex over (x)}, ŷ 1 , ŷ 2 corresponding to the series of bits x, y 1 , y 2 provided by the turbocoder supplying the transmitter are temporarily stored, and a memory area “data 2 — out” in which the output data obtained at the end of a decoding method according to the invention are temporarily stored.
The ROM memory 620 contains a memory area “P 2 ” in which a program implementing a decoding method according to the invention is recorded.
It should be noted that, in certain applications, it would be convenient to use the same computer device (functioning in multi-task mode) for the transmission and reception of signals according to the invention; in this case, the units 47 and 332 will be physically identical.
The methods according to the invention can be implemented within a telecommunication network, as shown in FIG. 12 . The network depicted, which can for example consist of one of the future communication networks such as UMTS networks, includes a so-called “base station” SB, designated by the reference 64 , and several “peripheral” stations SPi (i=1, . . . , N, where N is an integer greater than or equal to 1), respectively designated by the references 66 1 , 66 2 , . . . , 66 N . The peripheral stations 66 1 , 66 2 , . . . , 66 N are remote from the base station SB, each connected by a radio link with the base station SB and able to move with respect to the latter.
The base station SB and each peripheral station SPi can comprise a data processing unit 560 as described with reference to FIG. 8 , a transmission unit and a radio module provided with a conventional transmitter including one or more modulators, filters and an antenna.
The base station SB and each peripheral station SPi according to the invention can also comprise a data processing unit 660 as described with reference to FIG. 11 , a reception unit and a radio module with its antenna.
The base station SB and peripheral stations SPi can also comprise, according to requirements, a digital camera, a computer, a printer, a server, a facsimile machine, a scanner or a digital photographic apparatus.
OTHER EMBODIMENTS
The present invention is not limited to the embodiments described above: in fact, a person skilled in the art will be able to implement various variants of the invention whilst remaining within the scope of the accompanying claims.
Notably, the invention according to its first aspect applies, in addition to turbocoding, to any other method also using an interative decoder.
In general terms, for these iterative methods, instead of transmitting the successive values of IN as described above, it is possible, in an equivalent manner, to successively transmit the variations of IN, it being understood that the initial value of IN is known to the decoder in advance. Likewise, the value of IN transmitted may, instead of definitive values, be minimum values, the decoder deciding on the actual values according to additional criteria which will be chosen according to requirements.
In addition, it is very possible to advantageously combine the methods according to the invention with the “adaptive on reception” iterative decoding algorithms mentioned in the introduction, IN then serving as a guide for the decoder, amongst other criteria (for example the entropy of the signal received), in order to determine the required number of iterations.
It should be noted that the invention also applies, according to its second aspect, to non-iterative channel decoding methods in which there exists an adjustable factor controlling the decoding quality. According to the invention, the value of this factor for a corresponding block of data will (wholly or partially) be determined by the relative importance of this block of data within the whole of the message, this importance being expressed by the parameter according to the invention transmitted in association with said block of data.
Concerning the implementation of the invention in a telecommunications network, it should be noted that it may be a case either of a distributed architecture network or a centralised architecture network.
Finally, it is clear that the applications of the invention are in no way limited to the transmission of data representing images. In addition, even for the latter, it is perfectly possible to use a coding source other than coding by decomposition into sub-bands, for example a “coding by regions of interest” as defined by the standard JPEG-2000. | A method of transmitting blocks of data, in which, for at least one of the blocks of data, at least one parameter associated with this block of data is transmitted, the parameter representing the relative importance of the block of data associated with this parameter within the message transmitted by all the blocks of data. The data is coded by a channel coding method which does not take into account the parameter. Correlatively, the invention also concerns a decoding method associated with this transmission method. This way, data judged to be more important than other data may benefit from a channel decoding of higher quality. The methods described herein have application to devices and appliances implementing these methods. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to removable subassemblies in sealing equipment. Specifically, the invention relates to removable subassemblies in oil field rotary drilling head assemblies.
2. Background of the Related Art
Drilling an oil field well for hydrocarbons requires significant expenditures of manpower and equipment. Thus, constant advances are being sought to reduce any downtime of equipment and expedite any repairs that become necessary. Rotating equipment is particularly prone to maintenance as the drilling environment produces abrasive cuttings detrimental to the longevity of rotating seals, bearings, and packing glands.
FIG. 1 shows an exemplary drilling rig 10 . The drilling rig 10 is placed over an area to be drilled and a drilling bit (not shown) is attached to sections of drill pipe 12 . Typically, a rotary turntable 14 rotates a drive member 16 , referred to as a kelly, which in turn is attached to the drill pipe 12 and rotates the drill pipe to drill the well. In some arrangements, a kelly is not used and the drill string is rotated by a drive unit (not shown) attached to the drill pipe itself. Typically, a mixture of drilling fluids, referred to as mud, is injected into the well to lubricate the drill bit (not shown) and to wash the drill shavings and particles from the drill bit and then return up through an annulus surrounding the drill pipe 12 and out the well through an outflow line 22 to a mud pit 24 . New sections of drill pipe 12 are added to the drill pipe in the well using a crane 26 and a block and tackle 28 to collectively form a drill string 30 as the well is drilled deeper to the desired underground strata 32 . A power unit 34 powers a control unit 36 and associated motors, pumps, and other equipment (not shown) mounted on a drilling platform 38 .
In many instances, the strata 32 produce gas or fluid pressure which needs control throughout the drilling process to avoid creating a hazard to the drilling crew and equipment. To seal the mouth of the well, one or more blow out preventers (BOP) are mounted to the well and can form a blow out preventer stack 40 . An annular BOP 42 is used to selectively seal the lower portions of the well from a tubular body 44 which allows the discharge of mud through the outflow line 22 . A rotary drilling head 46 is mounted above the tabular body 44 and is also referred to as a rotary blow out preventer. An internal portion of the rotary drilling head 46 is designed to seal around a rotating drill pipe 30 and rotate with the drill pipe by use of a internal sealing element, referred to as a packer (not shown), and rotating bearings (also not shown) as the drill pipe is axially and slidably forced through the drilling head 46 . However, the packer wears and occasionally needs replacement. Typically, the drill string or a portion thereof is pulled from the well and a crew goes below the drilling platform 38 and manually disassembles the rotary drilling head 46 . Typically, a crane 26 is used to lift the rotary drilling head 46 which can weigh thousands of pounds. Because of the size of the drilling head 46 , portions of the drilling platform 38 and equipment are disassembled to allow access to the drilling head and to remove the drilling head from the BOP stack 40 . The drilling head 46 is replaced or reworked and crew goes below the drilling platform to reassemble the drilling head to the BOP stack 40 and operation is resumed. The process is time consuming and can be dangerous.
Prior efforts have sought to reduce the complexity of the drilling head replacement. For example, FIG. 2 is a schematic cross sectional view of a rotary blow out preventer, similar to the embodiments shown in U.S. Pat. No. 5,848,643, which is incorporated herein by reference. A rotating spindle assembly 48 is disposed within a non-rotating spindle assembly 50 , which in turn, is disposed within a body 52 and held in position by lugs 54 . To remove the entire non-rotating and rotating spindle assembly from the body 52 , lugs 54 are rotated in horizontal grooves 56 and then lifted upwardly through vertical slots 58 in a “twist and lift” motion. However, the assembly can weigh about 1,500 to about 2,000 pounds and still requires use of extra lifting equipment such as the crane 26 . In addition, disassembly of the drilling platform 38 is necessary to provide access and requires manual efforts by the drilling crew.
Similarly, U.S. Pat. No. 3,934,887, incorporated herein by reference, discloses a BOP body having an assembly of a lower stationary housing 22 and an upper stationary housing 24 . The upper stationary housing 24 houses a stationary tapered bowl 60 , a rotating bowl 62 disposed inwardly of the tapered bowl, and bearings 66 , 68 disposed between the stationary bowl and rotating bowl. A stripper 40 is connected to the rotating bowl 62 . A clamp 28 retains the assembly of the stationary tapered bowl 60 , the rotating bowl 62 , the bearings 66 , 68 , and associated equipment to the upper stationary housing 24 . By unclamping the clamp 28 , the entire assembly may be removed from the BOP body. However, the removable assembly is of such size and weight with the result that crews are needed below the drilling platform and lifting equipment is necessary to lift the assembly from the BOP body.
FIG. 3 is a schematic cross sectional view of another rotary BOP 60 , similar to the embodiments disclosed in U.S. Pat. No. 4,825,938, incorporated herein by reference. To avoid removing the entire rotary BOP, the reference discloses a pneumatically actuated series of “dogs” 64 which engage a groove 66 on a retainer collar 68 , referred to in that disclosure as “massive”. By actuating pneumatic cylinders 70 to rotate the dogs 64 away from the groove 66 , the “massive” retainer collar 68 , the stinger 72 , stinger flange 74 , a stripper rubber 76 , and associated bearing surfaces 78 , 80 and 82 can be removed and access gained to the inner structures to repair or replace the stripper rubber 76 . This device is similar to the preceding references in that both rotating and non-rotating portions are removed, which add weight and size to the assembly that is removed.
Another challenge to the rotary drilling head maintenance is bearing life. In a rotary BOP, bearings are used to reduce the friction between the fixed portions of the drilling head and the rotating drill string with rotating portions of the drilling head. As shown in FIG. 2, the typical assembly includes a lower bearing 84 and an upper bearing 86 axially disposed between a rotating portion 48 and a non-rotating portion 50 of the rotary BOP 50 . The bearings are tightened in position, referred to as pre-loading the bearing, by typically turning a threaded bearing retainer 88 until the bearings are pre-loaded to a desired level. As the bearings wear or otherwise change, the loading changes. The BOP must be disassembled, the bearing readjusted, and the BOP reassembled. Otherwise, the bearings can fail prematurely, causing downtime for the drilling operations. Typically, the bearing retainer is directly inaccessible after assembly into the drilling head and the drilling head must be at least partially disassembled for readjustment.
There remains a need for an apparatus and method for decreasing the downtime in drilling an oil well by decreasing the time required for removal and replacement/repair of the packer and decreasing the time required to adjust the bearing loading.
SUMMARY OF THE INVENTION
The present invention generally provides an apparatus and method for sealing about a member inserted through a rotatable sealing element disposed in a drilling head. The rotatable sealing element is removable separately from non-rotating and/or other rotating portions. More specifically, the invention allows a rotatable packer in a drilling head to be removable separately from non-rotating and/or other rotating portions of the drilling head. The invention also provides a fluid actuated system to maintain a pre-load system on the bearing.
In one aspect, the invention provides a non-rotating portion, a first rotating portion and a second rotating portion, at least one rotating portion being rotatably engaged with the non-rotating portion, and a selectively disengageable retainer disposed adjacent at least one of the rotating portions and adapted to disengage at least one of the rotating portions from the non-rotating portion. In another aspect, the invention provides a non-rotating portion, a rotating portion disposed in proximity to the non-rotating portion, at least one bearing disposed between the non-rotating portion and the rotating portion and having at least one moveable bearing race adjacent a remaining portion of the bearing, and an actuator disposed adjacent the bearing race and adapted to adjust a position of the moveable bearing race relative to the remaining portion of the bearing. In another aspect, the invention provides a method of retaining a packer in a drilling head, comprising disposing a packer in a rotating portion of the drilling head, radially moving a retainer toward the packer, the retainer being at least partially disposed in the rotating portion, and radially engaging the packer with the retainer while maintaining a portion of the retainer in the rotating portion. In another aspect, the invention provides a non-rotating portion, a packer disposed within the non-rotating portion, a retainer ring radially disposed about the packer, and an annular piston radially disposed about the packer and aligned with the retainer ring. In another aspect, the invention provides a method of releasing a packer from a drilling head, comprising disengaging a retainer from a packer and removing a packer from the drilling head while retaining rotating portions of the drilling head with the drilling head. In another aspect, the invention provides a method of adjusting bearing pressure in a drilling head, comprising rotating a rotating portion relative to a non-rotating portion using at least one bearing disposed therebetween, pressurizing a fluid port in said non-rotating portion fluidicly connected to a bearing piston with a fluid, and actuating the bearing piston toward a moveable bearing race adjacent a remaining portion of the bearing.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings.
It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1 is a schematic side view of a typical drilling rig.
FIG. 2 is a schematic cross sectional view of a prior art blow out preventer.
FIG. 3 is a schematic cross sectional view of another prior art blow out preventer.
FIG. 4 is a schematic partial view of a drilling rig using the present invention.
FIG. 5 is a schematic cross sectional view of one embodiment of a rotary drilling head, shown in split FIGS. 5A and 5B.
FIG. 6 is a schematic top view of the embodiment of FIG. 5 .
FIG. 7 is a schematic side view of a drive bushing.
FIG. 8 is a schematic cross sectional view of another embodiment of the invention, shown in split FIGS. 8A and 8B.
FIG. 9 is a cross sectional schematic view of another embodiment of the drilling head.
FIG. 10 is a cross sectional schematic view of another embodiment of the drilling head.
FIG. 11 is a partial cross sectional schematic of a subsea wellbore with a drilling platform disposed thereover.
FIG. 12 is a cross sectional schematic view of another embodiment of the drilling head.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention generally provides a removal system for a packer in a rotary drilling head and an adjustable loading system for bearing loads in the rotary drilling head. Preferably, the removal of the packer and adjustment of the bearing load can be done remotely through a hydraulic, pneumatic and/or electrical system external to the packer or bearing such as through a system mounted on the drilling head or a system distant from the drilling head itself.
FIG. 4 is a schematic partial view of a drilling rig 100 using the present invention. A stack 102 of flanged connections is located above the well 104 and connects one or more blow out preventers. An annular BOP 106 is disposed above the well in fluidic communication with the well drilling and production fluids. In the case of excess pressure in the well, the BOP will close the well and annular spaces 108 surrounding the drill string 110 in the well. Under normal conditions, the mud used to lubricate equipment in the well and flush drill shavings from a drill bit (not shown) is pumped through the outflow line 112 to mud pits (not shown). A rotary drilling head 114 , also referred to as a rotary BOP, is mounted above the outflow line 112 and assists in sealing the drill string 110 as the drill string slides axially through the internal rotary drilling head surfaces, i.e., axially with respect to the longitudinal axis of the drill string. A kelly 116 is attached to the drill string 110 and is inserted into the rotary drilling head 114 . The kelly 116 is typically hexagonal or square to transmit torque to rotatable portions of the drilling head 114 so that the rotatable portions rotate in conjunction with rotation of the drill string 110 and the kelly 116 . A power unit 118 is mounted in proximity to the stack 102 and provides power to operate the rotary drilling head 114 and associated system equipment on the rig 10 through hydraulic, pneumatic, and/or electrical circuitry. The power unit 118 can be mounted on a skid 120 for portability. The power unit 118 typically houses pumps, valving, motors, and reservoirs for the system within an enclosure 122 . In the embodiment shown, the system is simplified in that two pressure lines 124 travel to the rotary drilling head 112 and two pressure lines 126 travel to a control unit 128 mounted on the drilling platform 130 . The control unit 128 houses valving, meters, gauges, and other equipment and is designed to control the pressure and flow from the power unit 118 . While a hydraulic system is preferred, it is to be understood other systems such as pneumatic systems using gases, electrical systems and combinations thereof can also be used.
FIG. 5 shows a schematic cross sectional view of one embodiment of the drilling head 114 . The right side of the figure shows the drilling head 114 in an unengaged state without a drill string 110 disposed therethrough and the left side shows the drilling head 114 engaged with a drill string 110 axially disposed therethrough. The main components of the drilling head 114 generally include an annular lower housing 132 , an annular bearing housing 134 , an annular upper housing 136 , an annular packer 138 , an annular drive bushing 140 , a releasing element, such as a retainer ring 182 , and an actuator for the releasing element, such as a main piston 188 , and a lower body 142 .
The lower housing 132 of the drilling head 114 is attached to an annular lower body 142 which can be attached to the stack 102 , referred to in FIG. 4, through a flange 150 or other connection. Preferably, pins 144 are radially oriented about the circumference of the lower body 142 and engage recesses 146 on the lower housing 132 . The recesses 146 preferably are conically tapered to receive and engage a taper 145 on the pins 144 . The recesses 146 provide alignment between the lower housing 132 and the lower body 142 . The pins 144 can also engage a radial groove extending around the lower housing, instead of individual recesses. The lower body 142 can also include the main overflow line 148 .
The bearing housing 134 is attached to the lower housing 132 and engages an upper bearing 152 and a lower bearing 154 . A cap 156 is attached to the upper surfaces of the bearing housing and seals the upper bearing 152 from dust and other contaminants. The cap 156 preferably has a plurality of lifting eyes 158 . An inner housing 160 is disposed radially inward from the upper and lower bearings 152 , 154 and engages the upper and lower bearings. The upper housing 136 is attached to the upper portion of the inner housing 160 and supports the packer 138 disposed inwardly of the upper housing 136 .
The packer 138 includes a mandrel 206 a , which is an annular elongated metallic body, and an element 206 b coupled to the mandrel, known as a “stripper rubber”. The element 206 b can be non-pressure assisted, as shown in FIG. 5, or pressure assisted, as shown in FIG. 8 . The tubing string is inserted through the packer 138 and into the wellbore. The packer 138 is disposed inwardly from the upper housing 136 on an upper end of the packer and inwardly from the inner housing 160 on a lower end of the packer. The packer 138 is fixed in relative rotational alignment to the upper housing 136 and inner housing 160 by lugs 139 integral to or otherwise connected to the packer 138 that are disposed in axial slots 137 in the upper housing 136 . The element 206 b is made of elastomeric material such as rubber and is attached to the mandrel 206 a , such as by molding, and forms a sealing surface for the drill string 110 as the drill string axially slides through the rotary drilling head 114 . In an unengaged state, the element 206 b preferably is molded to be biased toward the centerline of the packer 138 . The element 206 b can deflect as the drill string 110 and shoulders 208 at joints on the drill string 110 pass therethrough. The drive bushing 140 is disposed radially inward from the packer 138 and engages tabs 162 on the packer 138 with slots 163 . A drive bushing 140 is not used in some instances when the drill string 110 is rotated without a kelly 116 . In such instances, the packer 138 preferably has sufficient frictional contact with the drill string 110 to rotate with the drill string without using the drive bushing 140 .
The upper bearing 152 comprises an inner race 172 , an outer race 174 , and a series of rollers 176 annularly disposed inside the bearing housing 134 and outside the inner housing 160 . The outer race 174 engages the bearing housing 134 and the inner race 172 engages the inner housing 160 . The upper bearing 152 is pre-loaded by a bearing actuator, such as an annular bearing piston 178 , disposed in an annular cavity 180 in the bearing housing 134 axially adjacent the outer race 174 of the upper bearing 152 . The bearing piston 178 engages the outer race 174 with pressure exerted from a hydraulic or pneumatic fluid applied to the bearing cavity 180 below the bearing piston 178 to move the outer race toward the rollers 176 and pre-load the upper bearing 152 and lower bearing 154 . The pre-loading force can be monitored and maintained or selectively changed remotely without removing the bearings and associated housings by maintaining or adjusting the fluid pressure exerted on the bearing piston 178 . Alternatively, a bias member (not shown) such as a spring can be used separately or in combination with the fluid pressure to pre-load the bearing. Such movements of the bearing race is deemed “remote” herein, in that the bearing race is moved by an additional member.
The lower bearing 154 likewise comprises an inner race 164 , an outer race 166 , and a series of rollers 168 annularly disposed inside the lower housing 132 . The outer race 166 engages a bottom portion of the bearing housing 134 and the inner race 164 engages an outside portion of the inner housing 160 . A lower bearing retainer 170 is threadably attached to the inner housing 160 . When the bearing piston 178 moves upwardly and engages the outer race 174 of the upper bearing 152 , the resulting force on the outer race 174 is transmitted through the upper bearing 152 to the inner housing 160 and tends to move the inner housing 160 upwardly. The inner race 164 on the lower bearing 154 moves upwardly with the inner housing 160 and exerts force on the rollers 168 of the lower bearing 154 to pre-load the lower bearing.
The combination of the lower and upper bearings allows axial and radial loads to be supported in the drilling head 114 as the drill string 110 is inserted therethrough and rotates the packer 138 , the inner housing 160 , the inner races 164 , 172 and the rollers 168 , 176 . The outer races 166 , 174 , bearing housing 34 , and lower housing 132 typically do not rotate. Lubricating fluid, such as hydraulic fluid, preferably is pumped through each bearing 152 , 154 to lubricate and wash contaminants from the bearings.
An annular retainer ring 182 is disposed in an annular ring cavity 184 formed between an upper portion of the inner housing 160 and a lower portion of the upper housing 136 . The retainer ring 182 is radially aligned with an annular groove 186 on the outside of the packer 138 and inward of the retainer ring 182 . Preferably, the retainer ring is “C-shaped” and can be compressed to a smaller diameter for engagement with the groove 186 . Preferably, in a radially uncompressed state, the retainer ring 182 does not engage the groove 186 and the packer can be removed. An annular main piston 188 is disposed in a lower cavity 190 in the inner housing 160 and protrudes into the ring cavity 184 . The main piston 188 is axially aligned in an offset manner from the retainer ring 182 by an amount sufficient to engage a tapered surface 192 on the outside periphery of the retainer ring 182 with a corresponding tapered surface 194 on the inside periphery of the main piston 188 . The main piston is connected to various fluid passageways for actuation. The retainer ring 182 has a cross section sufficient to engage the groove 186 and still protrude into the ring cavity 184 so as to limit the axial travel of the packer 138 by abutting the lower end of the upper housing 136 and the upper end of the main piston 188 . A bias member (not shown) can be disposed axially adjacent the end of the main piston 188 that is distant from the retainer ring 182 to provide an axial force to the main piston and pre-load the piston against the retainer ring. The bias member can be, for example, a spring, pressurized diaphragm or tubular member, or other biasing elements. An upper cavity 191 is disposed between the main piston 188 and the upper housing 136 and is separate from the ring cavity 184 . An indicator pin 202 is disposed in the upper housing 136 . On the lower end of the indicator pin 202 , the pin engages the upper end of the main piston 188 . The upper end of the indicator pin 202 is disposed outside the upper housing 136 , when the main piston 188 is disposed upwardly in the ring cavity 184 .
An assortment of seals are used between the various elements described herein, such as wiper seals and O-rings, known to those with ordinary skill in the art. For instance, each piston preferably has an inner and outer seal to allow fluid pressure to build up and force the piston in the direction of the force. Likewise, where fluid passes between the various housings such as the pistons, seals can be used to seal the joints and retain the fluid from leaking.
FIG. 6 is a schematic top view of the drilling head shown in FIG. 5 . The bearing housing 134 is circumferentially bolted to the lower housing (not shown) and the cap 156 is circumferentially bolted to the bearing housing 134 . The upper housing 136 is disposed radially inward of the cap 156 and is circumferentially bolted to the inner housing (not shown). The upper housing 136 includes two slots 137 in which lugs 139 on the packer 138 are inserted to maintain the relative rotational position of the packer 138 with the upper housing 136 and inner housing 160 . The drive bushing 140 is disposed radially inward of the packer 138 , is supported axially by the packer, and is radially fixed in position relative to the packer 138 by the slots 163 on the drive bushing when engaged with the tabs 162 on the packer 138 .
FIG. 7 is a schematic side view of the drive bushing 140 . The drive bushing 140 is designed to mate in two or more symmetrical portions 250 , 252 . Each symmetrical portion includes a tab 254 and a slot 256 on opposing sides formed between two or more flanges 258 , 260 , and bolt holes 262 through which bolts 264 are inserted through adjacent symmetrical portions, including the tabs and slots, to retain the symmetrical portions together. The bolts holes 262 are disposed axially, so that if the bolts 264 should be loosened in operation, the bolts would remain in place and the symmetrical portions 250 , 252 be retained together in contrast to a typical radial alignment for the bolts in which loose bolts could be thrown away from an assembled bushing by centrifugal force. The drive bushing 140 has an annular tapered surface 266 to mate with a corresponding tapered surface in the packer 138 , referenced in FIG. 6, and assist in securing the drive bushing axially in the packer.
In operation, referencing FIGS. 4-7, a crane 26 lifts the rotary drilling head 114 onto the stack 102 and the lower body 142 is attached to the stack with bolts in the flange 150 . One or more pins 144 in the lower body 142 engage the recesses 146 to secure both the axial and rotational positions of remaining portions of the drilling head 114 , i.e., those portions of the drilling head detachable from the lower body. Alternatively, the lower body 142 can be attached separately to the stack 102 and the remaining portions of the drilling head 114 attached to the lower body 142 with pins 144 . Fluid, such as hydraulic fluid(s) or pneumatic gas(es), is pumped into the drilling head 114 by the power unit 118 and controlled by the control unit 128 . To engage the retainer ring 182 with the groove 186 , the fluid is pumped into the lower cavity 190 and axially displaces the main piston 188 into engagement with the retainer ring 182 to force the ring radially inward. The engaged position of the retainer ring 182 with the groove 186 is shown on the left side of FIG. 5 . The force exerted between the tapers 192 , 194 compresses the retainer ring 182 radially inward to engage the groove 186 . The indicator pin 202 is pushed outward from the upper housing 136 by the travel of the main piston 188 to indicate the groove 186 is engaged. An assembly (not shown) can be bolted to the upper housing 136 to manually force the indicator pin 202 back into the upper housing 136 , thereby forcing the main piston 188 away from the retainer ring 182 to manually release the packer 138 if desired. Thus, the packer 138 , as a first rotating portion, is releasably retained in the drilling head 114 by the retainer ring 182 . Additionally, the fluid pressure can be maintained on the piston 188 even while the inner housing 160 and upper housing 136 rotate within the bearing housing 134 by the several seals, such as wiper seals and O-rings, located between non-rotating portions and other rotating portions of the drilling head, such as between the bearing housing 134 and the upper housing 136 or the inner housing 160 .
A drill string 110 , drilling bit (not shown), and a kelly 116 are assembled and inserted through the drive bushing 140 and the packer 138 . The element 206 b deflects radially outward as the drill string 110 is axially forced through the packer 138 and effects a seal about the periphery of the drill string. The kelly 116 is rotated which rotates the drill string, the drilling bit, and rotating components of the drilling head 114 for drilling a well.
When the packer 138 and particularly the element 206 b is to be replaced, the retainer ring 182 expands radially outward to disengage the packer 138 from the drilling head 114 . Fluid is forced into the upper cavity 191 and axially forces the main piston 188 away from the retainer ring 182 , whereupon the retainer ring decompresses radially outward and disengages the groove 186 , thereby releasing the packer from the non-rotating portions and other rotating portions. A pipe joint on the drill string 110 is separated and the upper portion of the drill string is removed from the drilling head 114 . Because of the relatively light weight of the packer 138 compared to the assembly of rotating components and especially compared to the entire drilling head 114 , neither the crane 26 nor special equipment may be needed to connect to the packer 138 and pull it from the drilling head 114 . The crane 26 may simply lift the drill string 110 and the element 206 b can rest on the pipe shoulder 208 and pull the packer 138 with the drill string 110 . The bearings 152 , 154 , upper housing 136 , inner housing 160 , cap 156 , bearing housing 134 , and lower housing 132 , all can remain attached to the lower body 142 .
The packer 138 may be reinserted into the drilling head 114 in the opposite manner. The packer 138 is placed on the drilling head 114 and rotated until the lugs 139 on the packer 138 are aligned with the slots 137 in the upper housing 136 and the packer then slides axially into position. The drive bushing 140 , if not already installed, is placed over the packer 138 , the slots 163 are aligned with the tabs 162 on the packer 138 , and the drive bushing is slid into position. The fluid pressure in the upper cavity 191 can be released and the fluid pressure in the lower cavity 190 forces the main piston 188 into engagement with the retainer ring 182 . The retainer ring 182 compresses radially inward and engages the groove 186 . The packer is thus secured and operations can be resumed.
FIG. 8 is a schematic cross sectional view of another embodiment of the drilling head. The embodiment shows two primary changes where one is to the packer 210 and the other to the manner in which the remaining portions of the drilling head 114 are retained to the lower body 142 . Any of the changes could be used with other embodiments and is not limited to the embodiment shown. In this embodiment, the other portions of the drilling head 114 remain substantially unchanged. The packer 210 includes a mandrel 212 a and a pressure assisted element 212 b is disposed radially inward from the mandrel and is axially bound by the mandrel on either end of the pressure assisted element. The pressure assisted element 212 b is shown in an unengaged mode on the right side of the centerline in FIG. 8 and in an engaged mode with a drill string 110 on the left side of FIG. 8. A port(s) 214 is disposed through the sidewall of the packer 210 radially outward from the pressure assisted element 212 b and is connected to fluid passageway(s) 213 leading to the power unit 118 and control unit 128 , referenced in FIG. 4. A drill string 110 having a shoulder 208 at each typical pipe joint is axially disposed through the drilling head 114 on the left side of the centerline. A cavity 216 in the engaged position shown on the left side of FIG. 8 is formed when fluid pressure forces the pressure assisted element 212 b toward the drill string 110 . The pressure assisted element assists in conforming the packer to variations in size and/or shape of different portions of the drill string, such as shoulder 208 , as the drill string is inserted through the drilling head.
An annular lower housing 218 is attached to an annular piston housing 220 disposed below the lower housing. An annular lower main piston 222 is disposed radially inward of the piston housing 220 and is housed in a lower ring cavity 224 formed between the lower end of the lower housing 218 , the inner periphery of the piston housing 220 , and a shoulder 226 of the piston housing 220 . A lower retainer ring 228 is disposed in the lower ring cavity 224 similar to the retainer ring 182 . The lower main piston 222 is axially aligned with the lower retainer ring 228 in an offset manner and engages the lower retainer ring 228 between tapered surfaces 230 , 232 . A lower groove 234 is formed on the outside circumference of the lower body 142 and is radially aligned with the lower retainer ring 228 . A wear ring 236 is disposed axially adjacent and below the lower retainer ring 228 . An upper cavity 238 is formed between the lower main piston 222 and a lower end of the lower housing 218 . A lower cavity 240 is formed between the lower main piston 222 and the piston housing 220 . A lower indicator pin 242 , similar to the indicator pin 202 , referenced in FIG. 5, is axially disposed in the piston housing 220 and aligned with the lower main piston 222 .
In operation, the remaining portions of the drilling head 114 can be inserted over the lower body 142 . Fluid is forced into the upper cavity 238 and applies pressure to the lower main piston 222 . The lower main piston slides axially and engages the lower retainer ring 228 between the tapered surfaces 230 , 232 , thereby radially compressing the lower retainer ring 228 into the groove 234 . The remaining portions of the drilling head 114 are thus secured to the lower body 142 . The lower main piston 222 forces the lower indicator pin 242 axially outward from the piston housing 220 , indicating an engaged mode. If the remaining portions of the drilling head 114 should need removal from the lower body 142 , fluid is forced into the lower cavity 240 , thereby axially displacing the lower main piston 222 away from the lower retainer ring 228 . The lower retainer ring 228 radially decompresses, disengages from the groove 234 on the lower body 142 and releases the remaining portions of the drilling head 114 for removal.
Furthermore, in operation, a drill string is inserted through the drilling head 114 and axially slides by the packer 210 . Fluid is transported through the port(s) 214 and expands the cavity 216 which in turn forces the pressure assisted element 212 b to radially compress against the drill string 110 . The amount of radial compression on the drill string can be controlled such as by regulating the pressure in the cavity 216 .
FIG. 9 is a cross sectional schematic view of another embodiment of the drilling head 114 . A lower body 280 generally houses the various rotating and non-rotating elements described in reference to the embodiment shown in FIG. 5 . The lower body 280 includes an attachment member, such as a flange 282 , which defines connecting holes 286 for bolts or other fasteners to pass therethrough into a mating flange (not shown) such as a flange disposed at the top of a well head casing. The lower body 280 also includes an attachment member, such as a flange 284 , which defines connecting holes 288 for bolts or other fasteners to pass therethrough for connecting the lower body 280 to a mating flange 294 on an upper body 292 . The upper body 292 is mounted to the lower body 280 in a sealing relationship with the flanges 284 , 294 and covers the various rotating and non-rotating members housed by the lower body 280 . The upper body also includes an upper flange 296 which defines holes 300 for bolts or other fasteners to pass therethrough into a mating flange (not shown), such as a flange disposed at the bottom of a casing extending downward from a drilling platform. The flange 284 of the lower body defines a lower body seal groove 290 and the flange 294 of the upper body defines an upper body seal groove 302 . The seal grooves 290 , 302 are sized and spaced in a cooperative relationship so that a seal 303 can be disposed therebetween to effect a seal between the flanges. Generally, the upper body and the lower body form an enclosure in connection with adjoining structure for protecting the bearings and packer of the drilling head from a radially external medium such as corrosive fluids, dirt, and other contaminates.
In general, various rotating and non-rotating members of the drilling head are disposed in a cavity 293 formed by the upper body 292 and lower body 280 . For example, the bearing housing 134 is mounted to the lower housing 280 by a fastening member 307 , such as one or more bolts, snap rings or other known fastening members, disposed within the cavity 293 . The fastening member 307 can also be an arrangement similar to the retainer ring 182 and main piston 188 , shown in FIGS. 5 and 8, that could engage the bearing housing 134 to the lower body 280 or the upper body 292 . The piston could be remotely actuated so that the bearing housing could be selectively fastened or released. A remote release or fastening could be particularly useful in remote locations such as in subsea applications. A packer 304 , similar to the packer 138 , is disposed within the drilling head 114 inward of an annular upper housing 136 . The packer 304 may extend upward to the elevation of the annular upper housing 136 . The packer 304 includes a mandrel 306 and an element 308 , similar to the mandrel 206 a and element 206 b , respectively, shown in FIG. 5 . The packer 304 is at least partially disposed in a cavity formed between the upper body 292 and the lower body 280 .
FIG. 10 is a cross sectional schematic view of another embodiment of the drilling head 114 , having members similar to those described in the embodiment shown in FIG. 8 . The lower body 280 includes a flange 282 which defines connecting holes 286 for bolts or other fasteners to pass therethrough into a mating flange (not shown) on an adjacent structure. The lower body 280 also includes a flange 284 which defines connecting holes 288 for bolts or other fasteners to pass therethrough for connecting the lower body 280 to a mating flange 294 on an upper body 292 . The upper body 292 is mounted to the lower body 280 in a sealing relationship with the flanges 284 , 294 and covers the various rotating and non-rotating members housed by the lower body 280 . The upper body also includes an upper flange 296 which defines holes 300 for bolts or other fasteners to pass therethrough into a mating flange (not shown) on an adjacent structure. The flange 284 of the lower body defines a lower body seal groove 290 and the flange 294 of the upper body defines an upper body seal groove 302 . The seal grooves 290 , 302 are sized and spaced in a cooperative relationship so that a seal 303 can be disposed therebetween to effect a seal between the flanges.
A packer 310 is disposed annularly within the annular upper housing 136 . The packer 310 includes a mandrel 312 and a pressure assisted element 314 that is disposed radially inward from the mandrel. The pressure assisted element 314 is axially bound by the mandrel on either end of the element. The pressure assisted element 314 is shown in an engaged mode with a drill string 110 that is axially disposed through the drilling head 114 . A port(s) 214 is disposed through the sidewall of the packer 310 radially outward from the pressure assisted element 314 and is fluidicly connected to a fluid pressure source. A cavity 216 is formed when fluid pressure forces the pressure assisted element 314 toward the drill string 110 . The pressure assisted element 314 assists in conforming the packer 310 to variations in size and/or shape of different portions of the drill string 110 as the drill string is inserted through the drilling head. The pressure assisted element 314 seals against the drill string 110 and allows differences in pressure between a first zone 316 and a second zone 318 for independent control of the pressures in the zones as described below.
FIG. 11 is a partial cross sectional schematic of a subsea wellbore 330 with a drilling platform 324 disposed thereover. The flanged embodiments shown in FIGS. 9 and 10 can be used in such an application. A casing 326 is suspended from the drilling platform 324 and extends a distance from the drilling platform to near the sea floor 328 . A drill string 110 is disposed within the casing so that an annular space 344 is formed therebetween. A flange 340 is connected to the lower end of the casing. A flanged drilling head 114 is sealingly connected to the flange 340 with a flange 296 disposed on the top surfaces of the drilling head. Similarly, a flange 286 disposed on the bottom surfaces of the drilling head 114 is sealingly connected with a flange 342 disposed on top of the wellbore 330 .
As the casing increases in depth, the weight of the water increases the pressure on the external surface of the casing. A sufficiently high pressure can distort or collapse the casing. A counteracting pressure within the annular space 344 in the casing can offset the effects of the external water pressure and minimize pressure differences. For example, the pressure differences can be minimized by flowing a fluid of similar density as sea water into the annular space to lessen the pressure gradient between the internal and external surfaces of the casing.
However, pressures necessary to drill into a subsea formation in the wellbore 330 may necessitate different pressures than those pressures required to offset the water pressure on the casing 326 . A drilling head 114 , such as the embodiment shown in FIG. 10, can be mounted between the casing and the wellbore. The pressure assisted packer 310 engages the drill string 110 and creates a first zone 316 above the packer 310 and a second zone 318 below the packer. A first set of pressures can be controlled in the first zone 316 to offset the pressures from the water as the casing increases in depth. A second set of pressures can be controlled in the second zone 318 to enable effective drilling into the various formations and production zones.
FIG. 12 is a cross sectional schematic view of another embodiment of the drilling head 114 , having members similar to those described in the embodiment shown in FIGS. 9 and 10. An upper body 350 is coupled to a lower body 280 with flanges 284 , 294 or other coupling members. Alternatively, the upper body 350 and the lower body 280 can be made as a unit with or without the flanges. A bearing housing 362 , similar to bearing housing 134 shown in FIGS. 9 and 10, is removably coupled to the upper body 350 and/or the lower body 280 . An upper housing 136 is disposed radially inward of the bearing housing 362 . A packer 310 is disposed radially inward of the upper housing 136 . A throat 352 of the upper body 350 is sized to allow the bearing housing 362 and related members to be disconnected from the upper or lower body and be retrieved therethrough.
One system for coupling the bearing housing 362 is similar to the system of a fastening member such as a retainer ring 186 and a piston 188 , shown in FIGS. 5 and 8 - 10 . As an example, the upper body 350 can include an annular piston cavity 354 in which a piston 356 is disposed and sealably engaged with a wall of the piston cavity. A first port 366 can be used to flow fluid, such as hydraulic fluid or pneumatic gases, to and from a first portion 354 a of the piston cavity to actuate the piston 356 . Another port 368 can be fluidicly coupled to a second portion 354 b of the piston cavity that is formed on an opposite portion of the piston 356 from the first portion 354 a of the piston cavity. Lines or hoses, such as line 369 coupled to port 368 , can deliver fluid to one or both of the ports. Line 369 can be disposed external to the upper body 350 and can be used to remotely actuate the piston. A retainer ring 358 is disposed adjacent an end of the piston 356 and in one embodiment is biased radially outward from the bearing housing 362 . The retainer ring 358 retains the bearing housing as one example of an assembly to the one or more of the surrounding bodies. Other assemblies, whether including one member or a plurality of members, can be retained by the retainer ring 358 . Mating surfaces between the retainer ring 358 and the piston 356 are preferably tapered to allow the piston to force the ring radially inward as the piston moves downward. A corresponding groove 360 formed in the bearing housing 362 is adapted to receive the retainer ring 358 when the retainer ring is biased inward toward the bearing housing. At least one seal 364 can be disposed between the bearing housing 362 and an adjacent surface of the upper body 350 to seal drilling fluids from portions of the piston cavity 354 .
The embodiment shown in FIG. 12 could also include other packers and related members, such as shown in FIG. 9 . Further, other members of the drilling head 114 could be coupled to the upper or lower bodies in lieu of or in addition to the bearing housing 362 .
In operation, fluid can flow through the port 366 into the first portion 354 a of the piston cavity 354 to force the piston 356 toward the retainer ring 358 . For example, fluid disposed in the throat 352 can flow through the port 366 into the piston cavity 354 to bias the piston 356 downward during operation. The piston 356 contacts the retainer ring 358 and forces the retainer ring radially inward toward the groove 360 on the bearing housing 362 . The retainer ring 358 engages the groove 360 and retains the bearing housing and related components to the upper body 350 . To release the bearing housing 362 from the upper body 350 , the piston 356 retracts from engagement with the retainer ring 358 . For example, fluid flown through line 369 , through port 368 and into the second portion 354 b of the piston cavity 354 can force the piston 356 upward and override the fluid pressure acting on the top of the piston through port 366 . The retainer ring 358 expands radially outward and away from the bearing housing 362 . A drill string 110 or other member disposed downhole can be used to lift the bearing housing 362 from the upper body to the surface of the well or drilling platform (not shown).
Variations in the orientation of the packer, bearings, retainer ring, rotating spindle assembly, and other system components are possible. For example, the retainer ring can be biased radially inward or outward. The pistons can be annular or a series of cylindrical pistons disposed about the drilling head. Various portions of the drilling head can be coupled to the upper and/or lower bodies besides the particular members described herein. Other variations are possible and contemplated by the present invention. Further, while the embodiments have discussed drilling heads, the invention can be used to advantage on other tools. Additionally, all movements and positions, such as “above”, “top”, “below”, “bottom”, “side”, “lower” and “upper” described herein are relative to positions of objects such as the packer, bearings, and retainer ring. Further, terms, such as “coupling”, “engaging”, “surrounding” and variations thereof, are intended to encompass direct and indirect “coupling”, “engaging” and “surrounding” and so forth. For example, a retainer ring can be coupled directly to the packer or can be coupled to the packer indirectly through an intermediate member and fall within the scope of the disclosure. Accordingly, it is contemplated by the present invention to orient any or all of the components to achieve the desired movement of components in the drilling head assembly.
While the foregoing is directed to the preferred embodiment of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | The present invention generally provides a reduced downtime maintenance apparatus and method for replacing and/or repairing a subassembly in sealing equipment for oil field use. The invention allows the removal of rotating portions of a rotary drilling head without having to remove non-rotating portions. The reduction in weight and size allows a more efficient repair and/or replacement of a principal wear component such as a packer. Specifically, the packer in a rotary drilling head can be removed independent of bearings and other portions of the rotary drilling head. Furthermore, because of the relatively small size and light weight, the packer can be removed typically without having to use a crane to lift a rotary BOP and without disassembling portions of the drilling platform. In some embodiments, the packer can be removed with the drill pipe without additional equipment. Furthermore, the packer can be removed remotely without necessitating manual disengagement typically needed below the platform. The invention also provides a fluid actuated system to maintain a pre-load system on the bearing. | 4 |
CROSS REFERENCES TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
THE NAMES OR PARTIES TO A JOINT RESEARCH AGREEMENT
Not applicable.
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
Not applicable.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to utilizing a user's—choice of a network connection in conjunction with location grade-of-service (GoS) information during network switching while roaming, and then using such information to promote environmentally friendly (or “eco-friendly”) management of wireless radios and other resources in a multi-radio device to save battery power based on available communication types. More particularly the present invention relates to a system and method for pinging presently non-active connection types at a slower rate than the active connection types, (assuming the user has a connection of some type) that still allow non-active connection types to be pinged at a less frequent interval to determine whether a connection is then possible (e.g., when the user has moved to a location where a connection may now be possible). Still more particularly, the present invention relates to a system and method for using the location information (actual coordinates of a mobile device) to “turn off” networks access devices for those network types that are known not to be in the area, thus significantly reducing power consumption by a multi-radio device.
2. Discussion of Related Art
Location information is used in a location-based service as a factor in determining when to switch connection type when roaming. A server is updated based on actual results from data points sent by connected devices, and those data points are then used to help determine when to “switch” connections while roaming for all devices in the local area in the future. The data points may include global coordinates in latitude and longitude (location), phone type, connection type (e.g., WiFi/CDMA/etc), signal strength, wireless provider, and so forth.
It would be advantageous to receive and use the above-described data points from the connected devices to build a “map” of what is available, wherein a “true” network grade of service map is dynamically updated based on connections of actual users in addition to previous connections from the connected device. By using this information, the system would recognize that a particular user is moving “out of” an area with good grade of service to an area that has better grade of service or to an area with a poor grade of service. The connected device would provide the user with warnings indicating that a service area is inferior, thus prompting the user to switch or take action by itself.
Devices equipped with multiple radios employ some form of connection management or session management software to manage connectivity associated with the devices. The typical functionality of such Connection Management software includes providing an interface to the user to facilitate connection to a wireless network, intelligently switching between networks, and provide other useful and well-known functions.
It would be further desirable, therefore, to enhance the Connection Management software and/or other such functionality in the device to add functionality enabling it to interact with the connected device's Operating System and/or the device drivers of the equipment using the wireless radios. Further, typically when a connected device equipped with multiple radio transceivers is powered up, the device comes up with all radios either turned on or in the last known state of the radios. Most users tend to leave the radios in that state, either because they are indifferent to the state of the radios, or because it is too difficult to change radio configurations. The present invention simplifies the selection of radio configurations and encourages users to select the most efficient configuration available, either manually or automatically.
BRIEF SUMMARY OF THE INVENTION
The present invention is a system and method for managing wireless network connections as well as the radios associated with making the wireless connections. The default behavior embedded in most device system software—including, but not limited to WINDOWS® 7, WINDOWS OS®, MAC OS®, ANDROID™, LINUX®, or variations thereof—do not have the ability to deal with the complexity associated with the management of multiple radios and associated environmental effects. The design of user interface of the software needs to be such that the actions taken, directly or by the natural movement of the user, automatically dictate the consequences of those decisions. [WINDOWS® and WINDOWS OS® are registered trademarks of Microsoft Corporation, Redmond, Wash.; MAC OS is a trademark of Apple, Inc., Cupertino, Calif.; ANDROID™, is a trademark of Google, Inc., Mountain View, Calif.; and LINUX™ is a registered trademark Linus Torvalds of Portland, Oreg.)
It is therefore a principal object of the present invention to provide a new and improved system and method to prevent large and needless consumption of power that results in rapid drainage of batteries, thereby leading to the need to recharge and replace batteries frequently. These actions increase electricity consumption, call for more manufacturing and disposal of batteries, and directly contribute to global warming, climate change, and increased toxin levels in landfills.
It is another object of the present invention to provide a new and improved method of creating and using a “map” of grade of service. Most telecommunication companies and mobile operators (Verizon, ATT, Sprint, etc.) have a “map” of its coverage areas. Most of the time such maps are either obsolete, inaccurate or highly optimistic. This inventive system provides software/technology onboard connected devices that creates an unbiased grade of service map based on actual reports from connected phones. The data points are sent through the system to a central server and include, but are not limited to, connection type, device battery level, signal strength, provider, location, and device type.
The present invention thus provides a method for connected devices to create an actual map of “grade of service” rather than a simple “coverage” map. A coverage map shows only where a given service provider may offer a signal of sufficient strength for connection to the system. The service provider may further classify the coverage map into a 2G, 2.5G or 3G coverage map based on the bearer's signal. A grade of service map, by contrast, takes into consideration the following parameters: (1) RSSI of the broadcast signal; (2) carrier-to-interferer ratios (or equivalents); (3) effective data rates (initial, sustained and average for the duration of connection); (4) throughput; (5) network capacity (measured as a “blocked data call”); (6) dropped connection; (7) type of device upon which the measurement was made; (8) carrier used when creating measurement; (9) date of measurement—such that changes in network coverage over time can be taken into account for connection decisions or displayed in a graphic map or other User Interface; (10) device battery level; and (11) other RF related parameters, however, not all of the parameters taken into consideration are identified above.
The information thus reported by a connected device using the inventive system and method is computed into a simplified “traffic light model.” This model classifies a given location or region into a green (good), yellow (moderate) or red (poor) grade of service zones based on the attributes of the device and carrier in use.
Not only can the inventive system predict a likely “coverage outage” for a device in transit and intelligently handle the possible loss of connection during downloads, but it can create a “real” map that shows coverage patterns in greater detail than maps for currently available systems. The system and method includes not only wireless connectivity, but other connection types as well. The system is also not limited to use on mobile phones; rather, it includes software for use on any network enabled device with a radio connection—all of which can send reports of locations (assuming GPS or radio-based location is also available), and Wi-Fi strength/details on the connection. The inventive system essentially creates a grid on the entire earth that maps all reports of type/strength for any wireless connection, provider, and so forth, and could optionally be used by a device and device holder to decide what service provider to use in view of where they live or travel, in combination with actual present signal strength.
Furthermore, and as yet another object of the present invention, there is provided a method of intelligently balancing a selected connection type and/or device radio type according to available battery life. Various connection types and corresponding radios have differing bandwidth capabilities and consume power at different rates. In some instances it may be more prudent to switch to a slower connection and radio type in order to conserve battery power. This contrasts with the assumed default election of choosing the fastest available connection type. Thus, the present invention allows the user to manually select a slower connection in order to conserve power or, alternatively, the system software may do so automatically in response to a predetermined multi-factor analysis.
An additional object of the present invention is to discover, collect, rate, and report alternative networks in the vicinity of the connected network. This information can be expressly reported to the server or queued for later communication. This includes networks available using the same technology used for the current connection (if device hardware supports it) and additional technologies present in the device that are already scanning for available networks (if the hardware is not powered down).
It is yet another object of the present invention to provide a new and improved method of detecting the “true limits” of the network. The resulting information, collected from potentially thousands or millions of devices, can be used to create a true grade of service map of the world which is continuously and automatically updated. The grades may be visually depicted using a colored coded scheme. A green zone, for instance, can be used to show where there are no reported failures—either in whole, or specifically for the same type of device in question. A red zone shows where there are no reported successes. And a yellow zone can be scaled to indicate the likelihood of success. For Wi-Fi this is done with the basic service set identifier (BSSID) since access points (APs) can use the same SSID. “Reports” from other users in an “area” (both past and present), with a weighting toward more current reports from devices, are used to more accurately predict what is likely to happen to the connection assuming the same vector. That is, the inventive system uses information regarding present connection strength (i.e., signal strength), combined with the vector (direction in which the device holder is traveling) to predict future connection strength.
Yet another principal object of the present invention is to provide a method to correlate network ratings to the user's system. This enables general metrics to be correlated to past performance of the user's device. For instance, if an entirely yellow gradient is measured between 0-100, based on previous experience for this technology it may be determined that the user's device fails at, for instance, 54. Based on this information, the grade of service map can then be customized for that user and the user can be advised according to his or her device's performance. Stated another way, the system will draw a coverage area specific to the device carried. The user's device, the network he uses, other users on the same network, users with the same device, and the direction in which the user is moving, are all considered in predicting what is about to happen for that user in the system.
Data can be used to do the following:
(a) Download the coverage shape upon connection to the network. If the service degrades or drops, the user is informed which way he should move to regain service and to obtain better service based on the coverage shape. Again, this can be linked to past performance of the user's device (as well as other results from different devices in the past). Ratings are based not just on what is happening to the current user but to others in the same area (past and present). A determination is made of the type: “If the user moves to yellow level 80 (30 feet north, their Wi-Fi connection will be excellent instead of ‘poor but usable’.”
(b) Download adjacent and alternative networks in the area and provide advice on better service using many metrics. If coverage drops, users are immediately notified with a user interface element indicating options. Triggers can be automatically predicted based on past experience of network failures for a specific device type correlated with collected statistics and providing advance warning of coverage drop. Trigger padding can automatically be applied warning of coverage drop well before it is likely to happen. Triggers can be automatically adjusted (and increased) if network coverage terminates before expected. Moreover, GPS location and travel velocity can be used to predict network failure. If the device is predicted to enter an area where failure is likely within some adjustable time limit, alternatives may be presented.
Various software metrics may be employed to rate networks, including:
(a) Technology and the area coverage, followed by rating the system, as possible, either as Excellent, Good, Normal, Fair, or Bad, based on how the coverage area of the particular location compares to other similarly tracked networks.
(b) Assigning metrics based on the duration of usage. For instance, if a user stays stably and reliably connected for a long period (8 hours, for instance), this indicates that the service is likely quite good. If, on the other hand, connections last for short periods of time only and the connections include frequent drops and disconnections from the same station, then the service may be deemed inferior.
(c) Assigning metrics based on repeat usage. If a device repeatedly uses a particular service and connection, it is deemed stable. A software metric is then used—such as 30% of all users are repeat users.
(d) Popularity metrics. These metrics may comprise a comparison between other networks of the same kind in the system.
(e) Rating the network based on how it is different from the carrier's estimation. This metric includes references to published network maps from common carriers and compares actual results from devices on that network.
A still further object of the present invention is to provide a method to automatically detect and disable an active transmission device while traveling on an airplane. When applied, the method assumes that the device holder has forgotten to disable the network communication functionality of the device. Since the device cannot legally be used while in flight, the inventive method is a power saving feature that disables network hardware contained in the device. This can be accomplished using a two step algorithm with an additional optional automatic functionality to return the device to its operational state when the airplane arrives at the destination airport. The inventive system detects when the device is inside or near an airport. This is done using GPS coordinates or by detecting the presence of a network known to include portions of the airport. This includes the connected network and/or a network detected by unconnected hardware which is powered on and scanning within the device.
Another object of the present invention is to provide a method for detecting when a network enabled device is on an airplane that is in the process of taking off or in the early stages of flight. This is accomplished using a GPS-enabled device, wherein the GPS is sampled and it is determined that the holder's device is moving faster than some predefined value (e.g., 200 mph). and/or the altitude of the device changes at some predefined rate (e.g., 500 ft/min). In the alternative, and in the event a GPS device is not present or powered off, it is possible to detect that the device moves through enough network service zones in a short enough period of time, and if such a condition is detected, the system can determine that the device is moving at speeds greater than typical terrestrial (automobile) speeds; for example, movement of faster than 100 mph.
Further, it is an object of the present invention to provide a method for a network enabled device to detect when a airplane has arrived at a destination airport and to automatically return the hardware in the device to a previous state. This can be accomplished by having GPS hardware in the device detect and report that the device is no longer moving and/or that the device has been at ground level for the airport location.
Accordingly, the present invention provides a system and method that relieves a device user of the need to make network connection decisions and to intelligently make those decisions on behalf of the user. The decisions will help the user conserve battery life and, in turn, help the environment by consuming less power from the device.
The foregoing summary broadly sets out the more important features of the present invention so that the detailed description that follows may be better understood, and so that the present contributions to the art may be better appreciated. There are additional features of the invention that will be described in the detailed description of the preferred embodiments of the invention which will form the subject matter of the claims appended hereto.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is a schematic diagram illustrating the general telecommunications environment in which the inventive system is practiced;
FIG. 2 is a schematic block diagram illustrating the general functional elements of a device equipped with multiple wireless radios and incorporating the inventive system for managing connectivity of the device;
FIG. 3 is a schematic diagram illustrating a portion of a tabbed user interface of the connection management or radio control software employed in the present invention;
FIG. 4 is a schematic flow chart illustrating the method steps of the inventive system when a user manually selects an Internet connection type from the tabbed user interface while in manual mode;
FIG. 5 is a schematic flow chart illustrating the method steps of the system while operating in automated mode;
FIG. 6 is a schematic flow chart illustrating the intelligence built into the inventive system using GPS-based tracking for automatically enabling and disabling the connected wireless device when traveling by airplane; and.
FIG. 7 is a schematic diagram illustrating the concept of a “Network coverage map,” in which circles having the highest density of dots signify “red” locations, or areas in which signal strength is determined to be poor, circles with no dots are “yellow” locations that have fair signal strength, and circles with medium dot density are “green” locations where signal strength is good to excellent.
DETAILED DESCRIPTION OF THE INVENTION
Definitions: As used herein, the term “Battery Life” is calculated using the following formula: Battery Life (Hour)=Battery Capacity (WHr)/Device Power Consumption (Watts)
Referring first to FIG. 1 , there is shown in greatly simplified schematic form the typical telecommunications environment in which devices using the invention system are used. The elements comprising the environment include a network enabled device 101 equipped with multiple radios having some kind of connection management or session management software to manage connections (including handovers) to fixed location transceivers, such as cellular radio towers 102 , and to satellites 103 (e.g., GPS satellites), using radio or other electromagnetic signals 104 .
Referring next to FIG. 2 , there is shown in simplified schematic form the kind of network enabled device 200 referred to above. This device includes a power control module 210 , a GPS radio 220 , multiple communications transceivers 230 , and software for managing radio control and the system manager as well as radio connectivity.
FIG. 3 is a highly simplified schematic diagram showing a small portion of a tabbed user interface 300 of a connection management software that enables the user to choose the radio interface or technology that the user wishes to use to connect to the Internet, including WWAN 310 and WLAN 320 (the latter which is used synonymously with IEEE 802.11-wireless LAN), and other connection methods 330 . The implementation is possible through other user interface design as well. However, the present invention uses a tabbed user interface by way of example. Thus, if a user holding a device at a Wi-Fi location (hotspot, home or corporate office) clicks on the Wi-Fi tab, it displays all available Wi-Fi networks and the user can either manually or automatically connect to one of the available Wi-Fi networks. Based on the user's choice the software can make a decision on whether to change the state of the other radios in the device.
It must be emphasized that in virtually all real world scenarios, most (if not all) users holding a multi-radio connected device have no reason to use more than one radio at a time. Thus, when a wireless device is connected to a Wi-Fi access point, there is no reason for the device user also to connect to a WWAN (HSPA or EV-DO) network. Even so, in majority of the devices presently used for wireless connections, a WWAN radio continues to be switched on even when a Wi-Fi connection is established. This is generally not understood or appreciated by the user, but it is a considerable waste of power resources on the device, as well as an environmentally “hostile” method of using the device. Thus, the present inventive method makes the wireless computing device to be more energy efficient and “green.”
Referring next to FIGS. 4 and 5 , it will be seen that the inventive method may be employed either manually or automatically, respectively, to determine and connect to the best available network and then to manage power consumption. FIG. 4 is a flow diagram 400 showing the typical steps involved when the device holder interacts with the device through a user interface to make a selection of a specific access method to establish an Internet connection. The manual mode forces the user to click 410 on one of the WWAN or WLAN or Other Connection Method tabs of the UI, thereby selecting the kind of connection desired. The system determines 420 the type of connection desired by the user and turns on the radio 430 associated with the access method selected by the user. The Connection Management software thus knows that the user has chosen the preferred access method and can therefore make an assumption, in majority of the cases, that the user has no need for other radios. Therefore, the Connection Management software confirms the selected access method 440 and when confirmed establishes the Internet connection 450 using the radio or the user's choice. It then turns off 460 other mobile broadband radios associated with access methods not selected by (e.g., the WLAN radio or Blue Tooth Radio, etc, when WWAN is the selected access method). When the confirmation step 440 returns a “No,” the system loops back to the step of determining the type of connection desired by the user.
Referring next to FIG. 5 , there is seen a schematic flow diagram 500 showing the operation of the inventive system in automatic mode. With the Computer Management software and the device in automatic mode 510 , the system automatically searches a technology preference and priority list and turns on 520 the radio associated with the device next appearing in the list. The system next initiates a search 530 to locate a network with which to connect, and if a network is found, the system connects 540 to the network and turns off radios not involved in the network connection. An Internet connection is thereby established 550 . If a network is not located at search step 530 , the system returns to searching the technology preference list and turns on the radio for the next preferred connection access technology 520 , and the process repeats until a connection is established or the available technologies are exhausted.
FIG. 6 is a schematic flow diagram 600 showing the inventive GPS-based method for tracking and automatically enabling or disabling connected wireless device when traveling by airplane. This feature of the inventive system is triggered when the connected device is in motion 610 . If at decision block 620 the device is determined to be powered on and the radio is turned on, the Cell Global Identity (“Cell ID”) or Base Station ID (“BSID”) is recorded 630 . Then, if at decision block 640 either the CellID or BSID are detected, the time of detection is recorded and searching for other CellIDs or BSIDs is continued for a reasonable period of time 650 . If a second CellID or BSID is detected 660 , the ID and time of detection are recorded and the speed of motion is of the connected device is computed 670 . If at decision block 680 the computed speed is not greater than terrestrial speeds, the system continues normal operation 690 . If, on the other hand, at decision block 680 the speed is computed to be greater than terrestrial speeds (as would be expected for airplane flight), or if at decision block 640 a Cell ID or BSID is not first detected, the device radios are turned off 700 to conserve battery power.
FIG. 7 is a schematic diagram illustrating a network coverage map 800 for use with the present invention. This kind of coverage a map is synthesized from a number of data points and depicts coverage through a variety of colored circles 810 superimposed on a detailed view 820 of an area map 830 . The circles, shown herein in black and white, include “red” circles 840 depicted here with a high density of dots and which signify areas in which signal strength is determined to be poor; “yellow” circles 850 , shown with no dots and which signify locations that have fair signal strength; and “green” circles 860 , depicted with medium dot density and signifying locations where signal strength is good.
The present invention enables wireless device manufacturers and device end users to more creatively manage battery life in a device, owing to the software technology available in multi-radio devices. For example, rather than use a default setting for a battery savings mode, a user can indicate, for instance, that he is going to be on a 5 hour flight and would like the battery to last 5 hours. In response to this indication, the inventive software will logically chose all the device settings required to meet this specification as closely as possible.
The above disclosure is sufficient to enable one of ordinary skill in the art to practice the invention, and provides the best mode of practicing the invention presently contemplated by the inventor. While there is provided herein a full and complete disclosure of the preferred embodiments of this invention, it is not desired to limit the invention to the exact construction, dimensional relationships, and operation shown and described. Various modifications, alternative constructions, changes and equivalents will readily occur to those skilled in the art and may be employed, as suitable, without departing from the true spirit and scope of the invention. Such changes might involve alternative materials, components, structural arrangements, sizes, shapes, forms, functions, operational features or the like.
Therefore, the above description and illustrations should not be construed as limiting the scope of the invention, which is defined by the appended claims. | A system and method for a connected wireless device to hand off from one network to another based on empirical data gathered from real live networks regarding the grade of service available on the network. The invention uses this information in combination with the user's choice of a preferred type of network connection to intelligently manage and conserve device battery life. | 8 |
BACKGROUND OF THE INVENTION
The present invention is directed to sequential fractionation of the contents of a centrifuge tube after the centrifugation operation and, more particularly, is directed to a fractionation system that can remove very small fraction volumes accurately and reproducibly without undesirable mixing of the fractions or losses of the fractions in a transfer tube or line. The system operates without requiring a motor, pump or electrical power.
After the centrifugation process, it is necessary to remove fractions of the separated contents in the fluid which has been subjected to centrifugation in order to proceed with the proper analysis of each separated constituent or level of fluid density. When using very small centrifuge tubes, the removal of precise small volumes or fractions of the fluid material from the centrifuge tube without losses or remixing presents a significant problem.
Many types of devices have been developed for fractionating the contents of centrifuge tubes. One such approach utilized in a fractionation system is tube slicing whereby the tube is sequentially cut into segments in a special holder and knife assembly so that the fluid can be removed with a pipette from each segment after it is cut. Although tube slicing has been used with some success in separating the contents in extremely small test tubes into only two fractions, the system of tube slicing is entirely impractical and unsuccessful for small tube sequential fractionation process.
Another process utilized for tube fractionation is puncturing whereby the tube is pierced with a hollow needle and the contents within the tube are collected slowly drop by drop as a result of applying a slight pressure to a space at the top of the tube. Another method for tube fractionation is the concept of displacement with the tube contents being displaced upward through a special cap assembly by injecting a heavy density fluid into the bottom of the tube by the use of a puncturing needle or by the use of a long capillary placed down into the centrifuge tube.
A final primary method used in tube fractionation is aspiration whereby the tube contents are removed in sequential elements from the top of the tube. This is typically done by a syringe either hand held or in a special holder. Also a special assembly using a vacuum pump to withdraw fractions of the tube contents through a capillary placed into the open top of the tube enables fractionation by the aspiration principle.
Typically, the methods presently used for tube fractionation provide a somewhat satisfactory approach when using larger centrifuge tubes of 5 milliliters or greater capacity, since losses of the fluid due to leaks or retention in the tubing connections can be tolerated. However, with respect to very small centrifuge tubes such as one holding as small as 0.175 milliliters of fluid, these methods of tube sequential fractionation do not provide satisfactory results. The volumes of fluid being handled in such small centrifuge tubes are so minute that losses due to leaks or retention in the tubing or as a result of remixing cannot be tolerated.
SUMMARY OF THE INVENTION
The present invention is directed to a sequential fractionation system utilizing a syringe-like apparatus whereby a chamber housing is connected to a frame in such a manner that the housing can be moved very precise distances relative to a plunger or piston within the chamber of the housing. Attached to the chamber housing are removable syringe tips that are used to collect the precise volume of fluid material for each sequential fractionation step. The present invention utilizes no motors or pumps eliminating the need for electrical power. Further, there is no need for connection tubing which would result in possible loss of the fluid volume remaining residually in the tubing.
The principal unique feature of the present invention is the manner in which the syringe-like apparatus is used to withdraw aliquots of the fluid contained in the centrifuge tube. The syringe barrel incorporated into the chamber housing is moved downward relative to the syringe piston, which is restrained from moving downward by contact with the top plate of the fractionator. This is in contrast to the usual operation of syringes in which the piston is withdrawn from the barrel held in a fixed position. This novel mode of operation permits fluid aliquots to be removed from the centrifuge tube in a particularly advantageous manner as explained below.
No fluid can be drawn into the syringe tip until it contacts the surface of the fluid in the tube. The start of the collection event cannot be initiated until contact is established by the syringe tip on the fluid surface. As the syringe tip and barrel are lowered, fluid is continuously withdrawn into the syringe tip only from the very surface of the contents within the tube which is a completely different operation from the prior art use of a syringe where the tip is immersed within the fluid and the fraction is withdrawn from below the surface rather than on the surface. The present method is essential to obtain sharp separation of fractions and to avoid mixing with fluid further down in the tube.
To achieve the above described action of the present invention the volume swept out by the movement of the syringe barrel relative to the piston must be equal to or greater than the volume of the fraction to be collected. This requirement is best met by making the diameter of the syringe barrel slightly larger than the inside diameter of the centrifuge tube. If desired, the syringe diameter can be considerably larger than the tube diameter, but some air may be drawn into the syringe tip with the fluid volume. However, this will not adversely affect the accuracy of the volume of the fraction.
The volume of the fraction collected is determined and controlled by measuring the distance which the chamber housing containing the syringe barrel is moved relative to its piston. This measurement is made conveniently by use of an attached measuring device which can accurately measure the movement of the chamber housing. The relationship between the distance moved and the actual volume collected can be calculated from a knowledge of the inside diameter of the centrifuge tube, but it is more accurate and convenient to determine the relationship by weighing fractions collected by movement of the chamber housing a particular distance in a preliminary fractionation using a centrifuge tube filled with water.
When the desired volume of the fraction has been drawn into the syringe tip, the chamber housing containing the syringe barrel is now raised. Since the syringe piston is not restrained by contact with the top plate, the piston will move upward with the chamber housing. Thus, the fluid in the springe tip will remain in place undisturbed.
The second unique feature of this invention is the fact that each fraction is contained entirely within the syringe tip and there is absolutely no loss due to leaks or retention of fluid in tubing connections. By removal of the tip, the fraction can be quantitatively transferred for subsequent use or analysis.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of the fractionation apparatus;
FIG. 2 is a partial sectional side elevational view of the apparatus;
FIG. 3 is a top partial sectional view of the fractionation apparatus; and
FIG. 4 is a sectional view taken along the lines 4--4 in FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
The fractionator device 10 of the present invention is shown in FIG. 1 having a base 12 on which is secured a frame member 14. At least three support pads or feet 15 are positioned in a balanced relationship on the bottom surface 34 of the base 12. As shown more clearly in FIG. 4, the frame member is an enlarged U-shaped one-piece member having a back portion 16 with integrally formed side panels 18 and 20 that extend perpendicular from the back portion 16. Located on the inside surface 22 of the side panels 18 and 20 and adjacent their free edges 24 are travel grooves 26. As shown in FIG. 1, a top plate 30 is secured over the frame member 14.
The travel grooves 26 are designed to receive a travel plate 28 that operates in a manner which will be discussed below. Securely mounted to the travel plate 28 in FIG. 1 is a chamber housing or hollow vessel 36 having an inner chamber 38 designed to receive a piston or plunger 40. The piston or displacement member has a flanged exterior end 42 which is larger than an aperture 44 in the top plate 30, so that movement of the piston 40 toward the base 12 is limited by the flanged end 42 contacting the top plate 30. The piston 40 has a head portion 46 which is designed to ride in sealing engagement within the cylindrical interior of the chamber 38.
As shown in both FIGS. 1 and 2, a swivel mounting or head 48 is attached to the chamber housing 36. The mounting 48 is designed to rotate annularly with respect to the housing 36 in FIG. 1. A coupling 50 is located on the swivel mounting and is designed to receive a removable syringe tip 52. The swivel mounting 48 has a junction arrangement 54 to rotatably affix the mounting on the chamber housing 36. The junction arrangement 54 is designed in such a manner to allow fluid communication between the coupling 50 of the swivel mounting 48 and the passage 56 which is in fluid communication with the cylindrical chamber 38 in which the piston 40 resides. Consequently, there is fluid communication between the open end 58 of the syringe tip 52 and the cylindrical chamber 38 within the chamber housing 36. The swivel mounting 48 is designed as shown in FIG. 1 to provide for more convenient insertion and removal of the syringe tip 52 as will be explained.
As shown in FIG. 2, located on the rear surface 60 of the travel plate 28 is a rack gear 62 having a plurality of teeth 64. Located in contacting relation with the rack gear teeth 64 is a pinion gear 68 having pinion gear teeth 66. The pinion gear 68 is rigidly mounted to a drive shaft 70 which is positioned and supported on and between the side panels 18 and 20 of the frame 14. Consequently, rotational movement of the drive shaft 70 will cause a corresponding movement of the rack gear 62 with the travel plate 28 which rides within the slots 26 of the side panels 18 and 20 of the frame 14. Located on each end of the drive shaft 70 are control knobs 72 which are designed to provide more accurate control movement of the travel plate 28 with the chamber housing 36 and syringe tip 52. Biasing means (not shown are used on the drive shaft to provide a slight resistance to the rotation of the knobs to enhance precise movement of the travel plate.
Also secured to the travel plate 28 as shown in FIG. 1 is a dial micrometer 74 having a gauge reference end 76 and a scaled measuring face 78 with rotatable indicator dial 80. Consequently, downward movement of the travel plate 28 will result in the gauge end 76 of the micrometer contacting the top surface 13 of the base 12.
Rotatably mounted on the base 12 in FIGS. 2 and 4 is a centrifuge tube holder 80 having a plurality of cavities 82 designed to receive a plurality of centrifuge tubes 84. The cylindrical holder 80 is connected to the base 12 by a screw or bolt 86 which also connects an indicator dial 88 to the base 12. Indicia 90 on the indicator dial wheel 88 are to identify and reference each of the centrifuge tubes 84.
Turning to the operation of the present fractionation system 10, attention is directed to FIGS. 1 and 2. After centrifugation of a series of fluid samples has been completed, the centrifuge tubes 84 are placed within the respective apertures 82 in the tube holder 80 of the fractionator 10. The travel plate 28 is positioned in its upper location with the top edge of the travel plate 29 being closely adjacent the top plate 30 of the device 10. A pipette or syringe tip 52 having a series of ribs 51 for easier grasping is inserted on the coupling 50 of the swivel head 48 that is connected to the housing 36. As shown in FIG. 1, the swivel mounting 48 is pivoted essentially to the position shown in phantom whereby the syringe tip can be more easily snapped into place over the coupling 50. The syringe tip, once securely placed on the swivel mounting 48, is rotated down to the vertical position as shown in solid lines in FIG. 1. The operator uses the control knobs 72 of the drive shaft 70 to rotate the pinion gear 68 to move the rack gear 62 and the travel plate 28 in a direction toward the base 12 of the device. When the operator notes that the open end 58 of the syringe tip 52 barely comes in contact with the top surface of the fluid contents in the test tube 84, the operator records the reading on the micrometer scale 78. By precise movement of the control knobs 72 the operator moves the syringe tip into the fluid noting the differential reading on the micrometer scale. When the reading on the scale corresponds to the precise volume desired, downward movement of the syringe tip is stopped.
Because the flanged end 42 of the plunger or piston 40 is restrained by the top plate 30 of the device, the downward movement of the chamber housing 36 in conjunction with the stationary piston head 46 will create a slight vacuum within the chamber 38. Further, the chamber 38 is made slightly larger than the size of the centrifuge tube 84 to enhance the creation of negative pressure in the chamber. Corresponding negative pressure which is caused within the chamber 38 will provide for the extraction of the fluid from the tube 84 as the syringe tip is lowered into the centrifuge tube. The fluid is withdrawn into the syringe tip off the very top surface of the level of contents of the tube. This alleviates any possible disturbance of subsequent fractions. Therefore, as the syringe tip is lowered, only the very top surface of the fluid is continually removed.
Once the desired volume of fluid is received within the syringe tip 52, the control knobs 72 are used to raise the travel plate 28 and retract the syringe tip 52 from within the test tube 84. It should be noted that, as the chamber housing 36 is raised with the travel plate, the flanged end 42 of the piston 40 is also raised above the top plate 30 so that the fluid is not extracted from the syringe tip as it is being raised. The operator then moves the syringe tip 52 to the horizontal position shown in phantom in FIG. 1 and gently removes the syringe tip for placement in a storage rack. In addition to the convenience provided in the removal of the syringe tip, this horizontal position also prevents the fluid in the tip from running out as the tip is removed.
A new syringe tip 52 is connected to the coupling 50 and the process repeated by extracting the next desired fraction from the contents within the centrifuge tube. Once all of the desired contents have been removed from the centrifuge tube, indicator plate 88 is rotated one notch to the next centrifuge tube to bring it in alignment with the syringe tip and the fractionation sequence is repeated on the full contents of another test tube.
Although the present invention is directed primarily to a fractionation device providing accurate and reproducible fractionation of fluid in a very small or extremely small test tube, the overall device could be scaled larger in size with increasing diameter of the chamber 38 so that it could be used for larger centrifuge tubes in density gradient experiments, for example, in conjunction with swinging bucket rotors and preparative ultracentrifuges. This device would provide the necessary fractionation with extreme simplicity, accuracy and convenience as compared to prior art fractionation systems.
The present invention describes a fractionation system device which allows for the fractionating of the contents in extremely small centrifuge tubes by the use of a simple mechanism that provides ultimate convenience and accuracy without the disadvantages of utilizing motors, pumps or electrical power as well as any connecting tube lines. The present invention is extremely versatile in the number of fractions collected and their size can be varied over a considerable range. | A device for the sequential fractionation of the contents of a centrifuge tube containing centrifugally separated contents utilizing a syringe-like apparatus. The present invention utilizes removable syringe tips that are mounted on a chamber housing for extraction and retention of a precise volume of centrifuged fluid from the centrifuge tube. The syringe-like apparatus is mounted to a frame in such a manner that the chamber housing is movable relative to the plunger or piston to permit precise movement of the chamber housing with the removable syringe tip into the centrifuge tube for delicate and precise removal of the desired fraction of the fluid. The syringe tips are removed with each fraction that is collected from the contents in the centrifuge tube and can be placed in a storage rack for subsequent analysis. | 6 |
CROSS-REFERENCE TO THE INVENTION
[0001] This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2004-379446, filed on Dec. 28, 2004; the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to a semiconductor manufacturing apparatus and a manufacturing method of a semiconductor device.
[0004] 2. Description of the Related Art
[0005] A robot arm is conventionally used when a wafer is placed on a lower electrode of a plasma processor. More specifically, a wafer is taken out of the carrier in a load lock chamber by a robot arm, and the wafer is conveyed to an orienter, by which deviation in the two-dimensional direction of the wafer with respect to the robot arm is corrected, and the wafer is conveyed into a plasma processing apparatus or in this state and is placed onto the lower electrode.
[0006] In the plasma processing apparatus, plasma treatment is performed for a wafer by generating plasma between an upper electrode and a lower electrode with the wafer placed on the lower electrode, and in order to effectively bring plasma into contact with the wafer, an annular focus ring is sometimes disposed on an outer peripheral edge portion of the lower electrode.
[0007] However, when the wafer is placed on the lower electrode in accordance with the above described procedure in the case where the focus ring is disposed, an error of about 500 μm to 1000 μm occurs to clearance between the wafer and the focus ring. Therefore, in-plane dispersion of characteristics occurs, for example, etching shape at the side near the focus ring becomes thin due to difference in plasma distribution, in the edge of the wafer, when etching of the wafer is performed, for example.
[0008] Here, an art of detecting a push pin provided at a stage by an optical sensor provided at a robot arm and placing a wafer on the stage is disclosed (for example, Japanese Patent Laid-open Application No. 2002-124556). However, even when the wafer is positioned with respect to the lower electrode by applying this art, the center of a focus ring and the center of the lower electrode are not aligned with each other in many cases, and therefore, it is difficult to make the clearance between the wafer and the focus ring constant.
SUMMARY OF THE INVENTION
[0009] According to an aspect of the present invention, a semiconductor manufacturing apparatus, including: a treatment chamber configured to house a substrate; an electrode which is disposed in said treatment chamber and on which the substrate is placed; a robot arm configured to convey the substrate to said electrode; and a sensor configured to detect a detection pattern of a focus ring which is disposed on an outer peripheral edge portion of said electrode, surrounds an peripheral edge of the substrate placed on said electrode and has the detection pattern, wherein clearance between the substrate and the focus ring is adjusted based on detection result of said sensor, is provided.
[0010] According to another aspect of the present invention, a manufacturing method of a semiconductor device, including: conveying a substrate by a robot arm into a treatment chamber in which an electrode is disposed and a focus ring having a detection pattern is disposed on an outer peripheral edge portion of the electrode, adjusting clearance between the substrate and the focus ring by detecting the detection pattern of the focus ring by a sensor provided at the robot arm and adjusting a position of the robot arm based on the detection result of the sensor, placing the substrate on the electrode while keeping the adjusted clearance, and performing plasma treatment for the substrate placed on the electrode, is provided.
[0011] According to still another aspect of the present invention, a manufacturing method of a semiconductor device, including: conveying a substrate by a robot arm into a treatment chamber in which an electrode is disposed and a focus ring having a detection pattern is disposed on an outer peripheral edge portion of the electrode, placing the substrate on the electrode so that the substrate and the focus ring are partially overlay each other and an outer periphery of the substrate is along the detection pattern of the focus ring, estimating actual positional relationship between the substrate and the focus ring by detecting the detection pattern of the focus ring in the state in which the substrate is placed on the electrode, and performing plasma treatment for the substrate placed on the electrode, is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a schematic diagrammatic view showing a semiconductor manufacturing apparatus according to a first embodiment.
[0013] FIGS. 2A and 2B are a side view including a schematic partial vertical sectional view and a plan view of an inside of an etching chamber according to first embodiment.
[0014] FIG. 3 is a side view including a schematically shown partial vertical sectional view of the inside of the etching chamber according to the first embodiment;
[0015] FIG. 4A to FIG. 4C are views schematically showing an operational situation of the semiconductor manufacturing apparatus according to the first embodiment.
[0016] FIG. 5A to FIG. 5C are views schematically showing the operational situation of the semiconductor manufacturing apparatus according to the first embodiment.
[0017] FIG. 6 is a side view including aschematic partial vertical sectional view of an inside of an etching chamber according to a second embodiment.
[0018] FIG. 7A and FIG. 7B are front views including a schematic partial vertical sectional view of an inside of an etching chamber according to a third embodiment.
[0019] FIG. 8A and FIG. 8B are a side view including a schematic partial vertical sectional view and a plan view of an inside of an etching chamber according to a fourth embodiment.
[0020] FIG. 9 is a view schematically showing an operational situation of a semiconductor manufacturing apparatus according to the fourth embodiment.
DETAILED DESCRIPTION OF THE INVENTION
FIRST EMBODIMENT
[0021] Hereinafter, a first embodiment will be explained. FIG. 1 is a schematic diagrammatic view of a semiconductor manufacturing apparatus according to this embodiment, and FIGS. 2A and 2B are a side view including a schematic partial vertical sectional view and a plan view of an inside of an etching chamber according to this embodiment. FIG. 3 is a side view including a schematically shown partial vertical sectional view of the inside of the etching chamber according to this embodiment.
[0022] As shown in FIG. 1 to FIG. 2B , a semiconductor manufacturing apparatus 1 includes a load lock chamber 2 in which a carrier (not shown) housing a plurality of wafers W (substrates) is disposed. A transfer chamber 3 is connected to the load lock chamber 2 , and an orienter 4 and an etching chamber 5 (treatment chamber) are connected to the transfer chamber 3 . The orienter 4 is for correcting a deviation in the two-dimensional direction of the wafer W with respect to a robot arm 6 which will be described later.
[0023] The robot arm 6 which supports the wafer W and conveys the wafer W is disposed in the transfer chamber 3 . The robot arm 6 is configured to be able to come and go freely to and from the load lock chamber 2 , the orienter 4 and the etching chamber 5 .
[0024] A disc-shaped lower electrode 7 (electrode) for placing the wafer W thereon is disposed in the etching chamber 5 . On the lower electrode 7 , an upper electrode (not shown) is disposed at a position opposed to the lower electrode 7 . In the state in which the wafer W is placed on the lower electrode 7 , etching gas is supplied into the etching chamber 5 and voltage is applied between the lower electrode 7 and the upper electrode, whereby plasma occurs and the wafer W is etched.
[0025] A retractable push pin 8 for placing the wafer W on the lower electrode 7 and for separating the wafer W from the lower electrode 7 is disposed on the wafer placing surface of the lower electrode 7 . When the wafer W is to be placed on the lower electrode 7 , the wafer W is placed on the push pin 8 by the robot arm 6 with the push pin 8 projected from the lower electrode 7 , and thereafter, the push pin 8 is lowered, whereby the wafer W is placed on the lower electrode 7 . On separating the wafer W from the lower electrode 7 , the wafer W is lifted by raising the push pin 8 with the push pin 8 housed in the lower electrode 7 , and thereby, the wafer W is separated from the lower electrode 7 .
[0026] A focus ring 9 is disposed on an outer peripheral edge portion of the lower electrode 7 to surround a peripheral edge of the wafer W placed on the lower electrode 7 . For example, an annular detection pattern 9 A is formed in the focus ring 9 .
[0027] The detection pattern 9 A is formed inside the focus ring 9 . As shown in FIG. 3 , the detection pattern 9 A may be formed on the surface of the focus ring 9 . The detection pattern 9 A is constituted of a material with a different reflection rate from that of a part 9 B (hereinafter, this part will be called “focus ring main body part”) of the focus ring 9 other than the detection pattern 9 A. In this embodiment, the case where the material constituting the detection pattern 9 A has a larger reflection rate than the material constituting the focus ring main body part 9 B will be explained. As an example in which the material constituting the detection pattern 9 A has a larger reflection rate than the material constituting the focus ring main body part 9 B, the case where the detection pattern is constituted of Al 2 O 3 , and the focus ring main body part 9 B is constituted of SiO 2 is cited, for example. It is possible to constitute the focus ring main body part 9 B of, for example, SiO 2 , Al 2 O 3 , C, Si and the like though it depends on the material quality of the film to be etched.
[0028] The robot arm 6 is provided with an optical sensor 11 (sensor) which is a part of clearance adjusting mechanism 10 . The clearance adjusting mechanism 10 is for adjusting clearance between the wafer W and the focus ring 9 , and is constituted of a controller 12 electrically connected to the optical sensor 11 other than the optical sensor 11 , and the like.
[0029] The optical sensor 11 is for detecting the detection pattern 9 A. More specifically, the optical sensor 11 is constituted of a projector, a light receiver and the like, and detects the detection pattern 9 A by irradiating the focus ring 9 with light by the projector, and detecting intensity of the reflected light reflected at the focus ring 9 by the light receiver. Here, in this embodiment, the material constituting the detection pattern 9 A has a larger reflection rate than the material constituting the focus ring main body part 9 B, and therefore, when the focus ring 9 is irradiated with light by the projector, the intensity of the light reflected at the detection pattern 9 A is larger than the intensity of the light reflected at the focus ring main body part 9 B.
[0030] As the projector, the one that generates light which is mainly reflected at the detection pattern 9 A and transmits through the focus ring main body part 9 B is preferable, and for example, a lamp, LED, laser or the like can be used.
[0031] The optical sensors 11 are provided at a plurality of spots of the robot arm 6 , for example, three spots. When the center of the wafer W and the center of the focus ring 9 are aligned with each other, the optical sensors 11 are disposed at positions where the intensities of the reflected light detected by the respective optical sensors 11 all become the maximum.
[0032] A controller 12 is for controlling an operation of the robot arm 6 and the like based on the detection result of the optical sensor 11 . More specifically, the controller 12 is configured to detect the position where the intensity of the reflected light detected by the optical sensor 11 becomes the maximum and determine the center position of the focus ring 9 , then determine a deviation amount from the current position to the center position of the focus ring 9 , and move the robot arm 6 by the deviation amount toward the center position of the focus ring 9 .
[0033] Hereinafter, an operation of the semiconductor manufacturing apparatus 1 will be explained. FIGS. 4A to 4 C and FIGS. 5A to 5 C are views schematically showing an operational situation of the semiconductor manufacturing apparatus 1 according to this embodiment.
[0034] As shown in FIG. 4A , the robot arm 6 enters the inside of the load lock chamber 2 , and takes the wafer W from the carrier. Subsequently, as shown in FIG. 4B , the wafer W is placed on the orienter 4 via the transfer chamber 3 . When the wafer W is placed on the orienter 4 , the deviation in the two-dimensional direction of the wafer W is corrected, and the wafer W is placed on the robot arm 6 again.
[0035] Thereafter, the wafer W is conveyed into the etching chamber 5 via the transfer chamber 3 as shown in FIG. 4C . In the etching chamber 5 , the robot arm 6 moves a very small distance while light reflected at the focus ring 9 is detected by the optical sensor 11 as shown in FIG. 5A . Subsequently, the positions where intensities of reflection light respectively become the maximum are detected by the controller 12 , and the center position of the focus ring 9 is determined. Next, a deviation amount from the current position to the center position of the focus ring 9 is determined by the controller 12 , and the robot arm 6 moves to the center of the focus ring 9 by the deviation amount. Thereby, the center of the wafer Wand the center of the focus ring 9 are aligned, so that the clearance between the wafer W and the focus ring 9 becomes constant.
[0036] Thereafter, the robot arm 6 descends, and as shown in FIG. 5B , the wafer W is placed on the push pin 8 projecting from the lower electrode 7 . When the wafer W is placed on the push pin 8 , the push pin 8 descends while maintaining the adjusted clearance between the wafer W and the focus ring 9 , and as shown in FIG. 5C , the wafer W is placed on the lower electrode 7 . Subsequently, etching gas is supplied into the etching chamber 5 by an etching gas supply mechanism (not shown), and voltage is applied between the lower electrode 7 and the upper electrode, whereby plasma occurs and the wafer W is etched.
[0037] In this embodiment, the detection pattern 9 A is detected by the optical sensor 11 provided at the robot arm 6 , and the position of the robot arm 6 is adjusted based on the detection result of the optical sensor 11 , whereby the center of the wafer W and the center of the focus ring 9 are aligned. Therefore, a variation of clearance between the wafer W and the focus ring 9 can be reduced, so that process stability can be enhanced.
[0038] In this embodiment, the optical sensors 11 are provided at the three spots of the robot arm 6 , and therefore, the center of the focus ring 9 can be easily and accurately determined. The optical sensors 11 may be provided at three or more spots of the robot arm 6 .
SECOND EMBODIMENT
[0039] Hereinafter, a second embodiment will be explained. In this embodiment, an example of using a metal detector as a sensor will be explained. In the same member and the like as the member explained in the first embodiment, the explanation will be omitted. FIG. 6 is a side view including a schematic partial vertical sectional view of the inside of the etching chamber according to the second embodiment.
[0040] In this embodiment, the detection pattern 9 A is constituted of the material with different magnetic permeability from that of the focus ring main body part 9 B. More specifically, the focus ring main body part 9 B is constituted of nonmetal when the detection pattern 9 A is constituted of metal, and when the detection pattern 9 A is constituted of nonmetal, the focus ring main body part 9 B is constituted of metal. In this embodiment, the case where the detection pattern 9 A is constituted of metal and the focus ring main body part 9 B is constituted of nonmetal will be explained.
[0041] As shown in FIG. 6 , the robot arm is provided with metal detectors 13 (sensors) which are part of the clearance adjusting mechanism 10 . The metal detector 13 is for detecting the detection pattern 9 A. More specifically, the metal detector 13 is constituted of a coil or the like, and detects the detection pattern 9 A by detecting change in impedance of the coil by an eddy current occurring to the surface of the detection pattern 9 A.
[0042] The metal detectors 13 are provided at three spots of the robot arm 6 . The metal detectors 13 are disposed at the positions where all the impedances detected by the respective metal detectors 13 are the maximum when the center of the wafer W and the center of the focus ring 9 are aligned.
[0043] The controller 12 is electrically connected to the metal detectors 13 , and is configured to detect the positions where the impedances detected by the metal detectors 13 become the maximum, determine the center position of the focus ring 9 and the deviation amount from the current position to the center position of the focus ring 9 , and move the robot arm 6 by the deviation amount toward the center position of the focus ring 9 .
[0044] Hereinafter, an operation of the semiconductor manufacturing apparatus 1 will be explained. Here, the operation of the robot arm 6 until the wafer W is conveyed into the etching chamber 5 , the operation of the push pin 8 after the wafer W is placed on the push pin 8 and the like are the same as in the first embodiment, and therefore, the explanation will be omitted.
[0045] In the etching chamber 5 , the robot arm 6 moves a very small distance while a change in impedance of the coil is detected by the metal detectors 13 . Subsequently, the positions where the impedances respectively become the maximum are detected by the controller 12 , andthecenterpositionof the focus ring 9 is determined. Next, the deviation amount from the current position to the center position of the focus ring 9 is determined by the controller 12 , and the robot arm 6 moves to the center position of the focus ring 9 by the deviation amount. Thereby, the center of the wafer W and the center of the focus ring 9 are aligned, and the clearance between the wafer W and the focus ring 9 becomes constant.
[0046] In this embodiment, the detection pattern 9 A is detected by the metal detectors 13 provided at the robot arm 6 , and the position of the robot arm 6 is adjusted based on the detection result of the metal detectors 13 , and therefore, the same effect as the first embodiment can be obtained.
[0047] In this embodiment, the case in which the detection pattern 9 A is constituted of metal and the focus ring main body part 9 B is constituted of nonmetal is explained, but the detection pattern 9 A may be constituted of nonmetal, and the focus ring main body part 9 B may be constituted of metal. In this case, the position where the impedance becomes the minimum is detected by the metal detector 13 , whereby the center of the focus ring 9 can be determined.
THIRD EMBODIMENT
[0048] Hereinafter, a third embodiment will be explained. In this embodiment, an example in which recessed and projected portions are formed on the focus ring will be explained. In the same member and the like as the member explained in the first embodiment, the explanation will be omitted. FIG. 7A and FIG. 7B are front views including schematic partial vertical sectional views of the inside of the etching chamber according to the third embodiment.
[0049] As shown in FIG. 7A , a recessed portion is formed on the surface of the focus ring 9 , and the recessed portion becomes the detection pattern 9 A. The projector of the optical sensor 11 is configured to irradiate light of which light diameter is larger than the width of the detection pattern 9 A. When the focus ring 9 is irradiated with light by the projector, there exist the place where light is reflected at only the focus ring main body part 9 B, and the place where light is reflected at the detection pattern 9 A and the focus ring main body part 9 B. Since in the place where light is reflected at the detection pattern 9 A and the focus ring main body part 9 B, the light reflected at the detection pattern 9 A differs in phase from the light reflected at the focus ring main body part 9 B and the intensity of the reflected light becomes small due to interference, the intensity of the reflected light becomes smaller than the intensity of the reflected light which is detected at the place where the light is reflected at only the focus ring main body part 9 B.
[0050] The controller 12 is configured to detect the position where the intensity of the reflected light detected by the optical sensor 11 becomes the minimum and determine the center position of the focus ring 9 , then determine the deviation amount from the current position to the center position of the focus ring 9 and move the robot arm 6 toward the center position of the focus ring 9 by the amount of deviation.
[0051] Hereinafter, the operation of the semiconductor manufacturing apparatus 1 will be explained. Here, the operation of the robot arm 6 until the wafer W is conveyed into the etching chamber 5 and the operation of the push pin 8 and the like after the wafer W is placed on the push pin 8 are the same as those in the first embodiment, and therefore, the explanation will be omitted.
[0052] In the etching chamber 5 , the robot arm 6 moves a very small distance while the light reflected at the focus ring 9 is being detected by the optical sensor 11 . Then, the positions where the intensities of the reflected light respectively become the minimum are detected by the controller 12 , and the center position of the focus ring 9 is determined. Next, the deviation amount from the current position to the center position of the focus ring 9 is determined by the controller 12 , and the robot arm 6 moves toward the center position of the focus ring 9 by the deviation amount. As a result, the center of the wafer W and the center of the focus ring 9 are aligned, and the clearance between the waferw and the focus ring 9 becomes constant.
[0053] In this embodiment, the detection pattern 9 A of the recessed portion is formed on the focus ring 9 and the detection pattern 9 A is detected by the optical sensor 11 provided at the robot arm 6 , and the position of the robot arm 6 is adjusted based on the detection result of the optical sensor 11 . Therefore, the same effect as in the first embodiment can be obtained.
[0054] In this embodiment, the case where the detection pattern 9 A is the recessed portion is explained, but as shown in FIG. 7B , the projected portion may be formed on the surface of the focus ring 9 and this projected portion may be used as the detection pattern 9 A. In this case, the center position of the focus ring 9 can be determined by detecting the position where the intensity of the reflected light becomes minimum by the optical sensor 11 .
FOURTH EMBODIMENT
[0055] Hereinafter, a fourth embodiment will be explained. In this embodiment, an example in which a deviation amount of the center position of the wafer and the center position of the focus ring is actually measured in the state in which the wafer is placed on the lower electrode so that the outer periphery of the wafer is along the detection pattern formed in the focus ring. The explanation will be omitted in the same members and the like as those explained in the first embodiment. FIG. 8A and FIG. 8B are a side view including a schematic partial vertical sectional view and a plan view of the inside of the etching treatment chamber according to this embodiment.
[0056] As shown in FIG. 8A and FIG. 8B , an outer peripheral edge portion of the lower electrode 7 becomes lower in height than in the other part of the lower electrode 7 , and on this outer peripheral edge portion, the focus ring 9 is disposed. A top surface of the inner peripheral edge portion of the focus ring 9 has substantially the same height as atop surface of the other part of the lower electrode so that the outer periphery of the wafer W partially overlays the inner peripheral edge portion of the focus ring 9 when the wafer W is placed on the lower electrode 7 , and a top surface of the other part of the focus ring 9 is not lower than a top surface of the wafer W.
[0057] Disc-shaped detection patterns 9 A are disposed at, for example, three spots in the inner peripheral edge portion of the focus ring 9 . In this embodiment, the detection patterns 9 A are disposed in the focus ring 9 , but they may be disposed on the surface of the focus ring 9 . As in the first embodiment, the annular detection pattern 9 A may be formed in the focus ring 9 or on the surface thereof.
[0058] The detection patterns 9 A are all formed into the equal sizes and the distances from the center position of the focus ring 9 to the detection patterns 9 A are all equal. In the state in which the center of the wafer W and the center of the focus ring 9 are aligned with each other, the detection pattern 9 A has a part of the detection pattern 9 A disposed at the position overlaying the wafer W. The detection pattern 9 A may be disposed at the position where the detection pattern 9 A and the wafer W circumscribe each other when the detection pattern 9 A is seen from directly above in the state in which the center of the wafer W and the center of the focus ring 9 are aligned with each other.
[0059] The detection pattern 9 A is constituted of the same material as that in the first embodiment. When the metal detector 13 is used as the sensor for detecting the detection pattern 9 A, the detection pattern 9 A may be constituted of the same material as in the second embodiment. A recessed portion or a projected portion may be formed at the focus ring 9 as in the third embodiment, and this may be used as the detection pattern 9 A.
[0060] The optical sensor 11 (first sensor) is controlled so as to detect the detection patterns 9 A in the state in which the wafer W is placed on the lower electrode 7 as well as detect the detection patterns 9 A before the wafer W is placed on the push pin 8 as in the first embodiment. In detection of the detection pattern 9 A in the state in which the wafer W is placed on the lower electrode 7 , intensity of light detected by the optical sensor 11 changes in accordance with the overlaying amount of the wafer W and the detection pattern 9 A. Namely, when the center of the wafer W and the center of the focus ring 9 are substantially aligned with each other, the overlaying amounts of the wafer W and the detection patterns 9 A at three spots are substantially equal to each other, and therefore, the intensities of light reflected at the detection patterns 9 A are substantially equal to each other. On the other hand, when the center of the wafer W and the center of the focus ring 9 are not aligned with each other, the overlaying amounts of the wafer W and the detection patterns 9 A at three spots are different from each other, and therefore, a variation occur to the intensities of light reflected at the detection patterns 9 A.
[0061] In this embodiment, the optical sensor 11 may not be provided at the robot arm 6 . Detection of the detection patterns 9 A in the state before the wafer W is placed on the push pin 8 and detection of the detection patterns 9 A in the state in which the wafer W is placed on the lower electrode 7 may be performed by using separate sensors (second sensor).
[0062] The controller 12 is configured to determine the deviation amount from the current position to the center position of the focus ring 9 based on the detection result from the optical sensor 11 as in the first embodiment and move the robot arm 6 toward the center position of the focus ring 9 by the deviation amount, before the wafer W is placed on the push pin 8 .
[0063] The controller 12 is configured to measure the actual deviation amount of the actual center position of the wafer W and the center position of the focus ring 9 by the optical sensor 11 , then perform etching for the wafer W in this state when the actual measured deviation amount is smaller than a predetermined deviation amount stored in the controller 12 , and place the wafer W on the lower electrode 7 again when the actual measured deviation amount is larger than the predetermined deviation amount.
[0064] Hereinafter, an operation of the semiconductor manufacturing apparatus 1 will be explained. Here, the operation and the like of the robot arm 6 and the push pin 8 until the wafer W is placed on the lower electrode 7 is the same as in the first embodiment, and therefore, the explanation will be omitted. FIG. 9 is a view schematically showing the operational situation of the semiconductor manufacturing apparatus 1 according to this embodiment.
[0065] The detection patterns 9 A are detected by the optical sensor 11 as shown in FIG. 9 in the state in which the wafer W is placed on the lower electrode 7 , and based on the detection result of the optical sensor 11 , the actual deviation amount of the center position of the wafer W and the center position of the focus ring 9 is measured. Namely, the current center position of the wafer W is determined by comparing the intensities of light reflected at the detection patterns 9 A by the controller 12 , and the actual deviation amount is determined by the determined current center position of the wafer W and the center position of the focus ring 9 .
[0066] When the actual deviation amount is smaller than a predetermined deviation amount, etching is performed for the wafer Win this state. On the other hand, when the measured actual deviation amount is larger than the predetermined deviation amount, the push pin 8 rises to separate the wafer W from the lower electrode 7 . Thereafter, the wafer W is supported by the robot arm 6 , and the robot arm 6 moves toward the center position of the focus ring 9 by the actual deviation amount. Thereafter, the wafer W is placed on the push pin 8 again, then the push pin 8 is lowered to place the wafer W on the lower electrode 7 again. Subsequently, the actual deviation amount of the center position of the wafer W and the center position of the focus ring 9 is measured again. These operations are repeatedly performed until the actual deviation amount becomes smaller than the predetermined deviation amount.
[0067] In this embodiment, the actual deviation amount of the current center position of the wafer W and the center position of the focus ring 9 is measured in the state in which the wafer W is placed on the lower electrode 7 , and therefore, the deviation amount can be accurately grasped. Namely, even when the clearance between the wafer W and the focus ring 9 is adjusted before the wafer W is placed on the lower electrode 7 , there is the possibility of the position of the wafer W being deviated, for example, when the push pin 8 on which the wafer W is placed is lowered, or when the wafer W is placed on the push pin 8 . On the other hand, in this embodiment, the actual deviation amount of the current center position of the wafer W and the center position of the focus ring 9 is measured in the state in which the wafer W is placed on the lower electrode 7 , and therefore, the deviation amount can be accurately grasped when the center of the wafer W and the center of the focus ring 9 are deviated from each other.
[0068] In this embodiment, actual positional relationship of the wafer W and the focus ring 9 is estimated in the state in which the wafer W is placed on the lower electrode 7 , and when the actual deviation amount of the current center position of the wafer W and the center position of the focusring 9 is larger than the predetermined deviation amount, the deviation is corrected based on the actual deviation amount. Therefore, the center of the wafer W and the center of the focus ring 9 can be reliably aligned, and the clearance between the wafer W and the focus ring 9 can be made constant.
[0069] The present invention is not limited to the description of the above described embodiments, and the structure and material, disposition or the like of each component can be properly changed without departing from the spirit of the present invention. For example, the example in which the focus ring 9 is incorporated in the etching chamber 5 is explained in the first to fourth embodiments, but any apparatus using plasma such as, for example, an ashing apparatus and a plasma CVD apparatus can be applied. | According to an aspect of the present invention, a semiconductor manufacturing apparatus, including: a treatment chamber configured to house a substrate; an electrode which is disposed in said treatment chamber and on which the substrate is placed; a robot arm configured to convey the substrate to said electrode; and a sensor configured to detect a detection pattern of a focus ring which is disposed on an outer peripheral edge portion of said electrode, surrounds an peripheral edge of the substrate placed on said electrode and has the detection pattern, wherein clearance between the substrate and the focus ring is adjusted based on detection result of said sensor, is provided. | 7 |
This application claims benefit of provisional application Ser. No. 60/015,518 filed Apr. 16, 1996.
BRIEF DESCRIPTION OF THE INVENTION
This invention relates to a cordless tool which can be a multipurpose tool including a not melt glue gun function of a type which avoids the necessity for electric power or can be simply a cordless glue gun depending upon the design preferred.
Glue guns are well known which use electric power to heat a sleeve through which a stick of hot melt glue can be fed so that the stick melts within the sleeve to allow the gun to squeeze the melted glue through a nozzle tip for effecting a hot melt gluing action.
Proposals for cordless hot melt glue guns have previously been made in which the electric power is supplied by rechargeable battery. This is however inconvenient and relatively heavy.
It is one object of the present invention, therefore, to provide an improved cordless tool which includes a hot melt glue gun function.
According to one aspect of the invention there is provided a cordless glue gun comprising a sleeve for receiving a stick of hot melt glue for sliding therethrough, a tip at a forward end of the sleeve for discharging the glue when melted, and a gas burner for heating the sleeve so as to melt the glue.
BRIEF DESCRIPTION OF THE DRAWINGS
One embodiment of the invention will now be described in conjunction with the accompanying drawings in which:
FIG. 1 is a side elevational view of a first embodiment of the invention.
FIG. 2 is a side elevational view of a second embodiment of the invention.
FIG. 3 is a side elevational view of a third embodiment of the invention.
FIG. 4 is a front elevational view of the embodiment of FIG. 3 showing the housing partly in cross-section.
DETAILED DESCRIPTION OF THE INVENTION
Referring firstly to FIG. 1, the apparatus as shown comprises a housing including an upper housing part 10 and a lower housing part 11 which can be engaged onto a portion 10A of the upper housing part as a sliding or friction fit so that the parts clip together to enclose a hollow interior. A reservoir or container 20 of butane is provided within the hollow interior of the housing. At the top of the housing is mounted a glue dispensing system including a metal sleeve 3 which acts as a thermal body and guide support for a glue stick 21 to be fed through the sleeve 3 to a replaceable metal discharge nozzle 2 at a forward end of the sleeve 3.
Behind the sleeve 3 is mounted a plastics tube 4 which can be formed of fiberglass or similar material and acts as an insulator to prevent the heat from the sleeve 3 from communicating along the glue stick to a rear part of the glue stick. Only a forward part of the glue stick which is within the sleeve 3 and within the nozzle 2 is therefore heated and can be discharged from a forward end of the nozzle 2. The plastic sleeve 4 is support in a rear collar 4A mounted on the housing and coaxial with the sleeve 3. A strap 4B interconnects the sleeve 3 and the collar 4A. The glue stick is moved forwardly by a stick advancing collar 5 carried on an actuating arm 6. The arm 6 is reciprocated by a trigger 9 through a linkage 9A so that the reciprocation of the arm 6 causes a pushing action on the glue stick 21 as the collar moves forwardly and allows the collar to be retracted over the glue stick in the return direction of reciprocation for a further pushing stroke.
On the underside of the sleeve 3 integrally connected therewith or in intimate contact therewith is provided a catalytic heater 1 of the type comprising a surrounding sleeve of metal containing a porous catalytic material so that injection of the gas from a feed line 22 into one end of the sleeve causes the gas to be fed into the porous material and allows the gas to be burned within the porous material with the combustion products escaping through holes or slots 23 in the outside of the sleeve surrounding the catalytic material. Thus the injection of the gas into the catalytic burner can be ignited by an igniter wheel 7 of conventional construction located underneath the burner 1 so that heat from the burner is applied directly to the sleeve to effect heating of the sleeve throughout the full extent of the sleeve so as to heat the glue stick within the sleeve to effect melting of the glue within the sleeve. The igniter wheel 7 includes a flint replacement screw 13 containing a flint 13A so that rotation of the wheel generates sparks from the flint to effect lighting of the burner.
The supply line 22 includes a valve 24 which is actuated by a heat control dial or switch 8 which has a number of positions movable from a first off position in which the valve is closed through minimum open to maximum open positions in a number of selectable steps.
The lower housing portion 11 includes a base 12 which allows the element to be positioned in standing position on a support surface. At the base, a portion of the container 20 is exposed to provide a filler opening 25.
The tip 2 can be removed and replaced by a plug 14 so as to close off the sleeve 3 and prevent the use of the device as a glue gun. The burner 1 can be removed and replaced by one of a plurality of interchangeable tips 15 which provide a number of different tools or uses for example a soldering iron, a hot knife, a blow torch or a heat blower.
The tool therefore is completely cordless and powered by butane or other similar gas material and has the possibility for use either as a glue gun or as a tool providing one of the other uses set forth above.
In FIG. 2 is shown a similar arrangement but in this case the burner 1A surrounds the sleeve 2 so as to provide more direct heating of the sleeve 3. In addition the housing contains a conventional cigarette lighter 30 which is used as a removable reservoir for the gas supply. In this arrangement the control of the amount of gas can be effected by operating the conventional control lever on the lighter so that the switch 8 is used solely as a control for operating the compression of the conventional switch 31 on the lighter.
FIGS. 3 and 4 show a yet further embodiment similar to the embodiment of FIG. 1 but modified by the following features.
Firstly the trigger 9 and linkage 9A are replaced by a breach pad 30 which includes two sliding side guides 31 and 32 each slidable within a rail or recess in the side wall of the housing so as to guide the breach pad in forward and rearward movement relative to the housing. The breach pad carries an arm 6A which stands normally upwardly from the breach pad but can be twisted to one side to allow insertion of a glue stick. The arm 6A carries a collar 5A with an end plate 5B which abuts the end of the glue stick and applies forward pressure when the pad 30 is pressed forwardly by a squeezing action of the hand of the user relative to finger grooves in a front of the housing. Thus the sliding breach loader is retracted to fit a glue stick into the fiber guide 4. Once loaded the glue stick is manually fed forwardly by exerting slightly palm pressure against the breach pad.
When operating the glue gun, the butane gas adjust slide control 8 is operated to set the gas flow at maximum setting of three. The ignition wheel 7 is rotated to ignite the gas at the openings 23 in the burner. Once the tip is heated sufficiently, the slide control can be slightly reduced to prevent overheating of the glue stick. The fluidity of the glue stick can be determined by squeezing a small portion from the tip 2 and can be adjusted by effecting movement of the slide control 8 between the minimum and maximum settings.
In addition in FIG. 3, the construction of the burner 1 is shown in a little more detail in the exploded view. Thus the burner 1 includes a gas injector 40 which is located in the housing with a screw threaded end engaged into the housing and a forward end projecting into the interior of the burner 1. The forward end includes a threaded coupling 41 which receives a rear end 42 of a catalytic heater valve. Thus the sleeve forming the burner remains in place attached to the sleeve 3 or integral therewith so as to allow direct communication of heat. However the valve carrying the porous catalytic material can be inserted into the sleeve and screwed into engagement with the threaded coupling 41 of the injector 40. A screw head 44 of the valve allows the screwing action and this is visible at the front of the sleeve. The valve 43 can be removed and replaced when worn.
When it is intended to use the device for purposes other than the glue gun, the tip 2 is removed and replaced by the end plug 14. In addition the valve 43 is removed and is replaced by one of the replaceable tips 15A, 15B, 15C and 15D.
The tip 15A comprises a blow torch so that it does not use the catalytic burner arrangement but instead comprises a tube which is inserted into the sleeve of the burner and is threadedly engaged onto the coupling 41 of the injector. A forward end of the tip 15A projects outwardly from the sleeve of the burner and provides a conventional blow torch nozzle so that the gas is ignited at the front of the blow torch nozzle and does not in any way heat the burner 1.
The tip 15B comprises a soldering tip which again is inserted into the sleeve of the burner and coupled onto the coupling 41. In this case the catalytic burner section of the tip is aligned with the sleeve of the burner so that the gas combustion products can escape while heating the tip 15B so that a forward end is heated for soldering purposes.
The tip 15C comprises a cutting knife which is similar in construction to the tip 15B but includes at the forward end a knife blade which is heated by the catalytic burner. The tip 15D comprises simply an insertion into the sleeve of the burner so that the gas emerges from the front end of the burner without escaping through the openings 23 and can be ignited at the front of the burner. Appropriate temperature setting is achieved by the slide control 8 as previously described. | A cordless tool which includes a glue gun function and may include other functions includes a sleeve for receiving a stick of hot melt glue for sliding through the sleeve and a tip at the forward end of the sleeve for discharging the glue when melted. A butane heated gas burner heats the sleeve using gas permeable catalytic heater which surrounds or lies in intimate contact with the sleeve to communicate heat to the sleeve. The arrangement can be modified by closing off the catalytic heater for use to provide multi function. | 1 |
RELATED APPLICATIONS
This application claims priority from U.S. Provisional Application No. 60/269,646, filed Feb. 16, 2001.
TECHNICAL FIELD
This invention relates to laser processing of circuit links and, in particular, to a laser system and method employing a laser beam and substrate positioning system that incorporates a steering mirror to compensate for stage positioning errors and enhance link severing throughput.
BACKGROUND OF THE INVENTION
Yields in integrated circuit (“IC”) device fabrication processes often incur defects resulting from alignment variations of subsurface layers or patterns or particulate contaminants. FIGS. 1, 2 A, and 2 B show repetitive electronic circuits 10 of an IC device or workpiece 12 that are typically fabricated in rows or columns to include multiple iterations of redundant circuit elements 14 , such as spare rows 16 and columns 18 of memory cells 20 . With reference to FIGS. 1, 2 A, and 2 B, circuits 10 are also designed to include particular laser severable circuit links 22 between electrical contacts 24 that can be removed to disconnect a defective memory cell 20 , for example, and substitute a replacement redundant cell 26 in a memory device such as a DRAM, an SRAM, or an embedded memory. Similar techniques are also used to sever links to program a logic product, gate arrays, or ASICs.
Links 22 are designed with conventional link widths 28 of about 2.5 microns, link lengths 30 , and element-to-element pitches (center-to-center spacings) 32 of about 8 microns from adjacent circuit structures or elements 34 , such as link structures 36 . Although the most prevalent link materials have been polysilicon and like compositions, memory manufacturers have more recently adopted a variety of more conductive metallic link materials that may include, but are not limited to, aluminum, copper, gold nickel, titanium, tungsten, platinum, as well as other metals, metal alloys such as nickel chromide, metal nitrides such as titanium or tantalum nitride, metal suicides such as tungsten silicide, or other metal-like materials.
Circuits 10 , circuit elements 14 , or cells 20 are tested for defects. The links to be severed for correcting the defects are determined from device test data, and the locations of these links are mapped into a database or program. Laser pulses have been employed for more than 20 years to sever circuit links 22 . FIGS. 2A and 2B show a laser spot 38 of spot size diameter 40 impinging a link structure 36 composed of a link 22 positioned above a silicon substrate 42 and between component layers of a passivation layer stack including an overlying passivation layer 44 (shown in FIG. 2A but not in FIG. 2B) and an underlying passivation layer 46 (shown in FIG. 2B but not in FIG. 2 A). FIG. 2C is a fragmentary cross-sectional side view of the link structure of FIG. 2B after the link 22 is removed by the laser pulse.
FIG. 3 is a plan view of a beam positioner travel path 50 performed by a traditional link processing positioning system. Because links 22 are typically arranged in rows 16 and columns 18 (representative ones shown in dashed lines), the beam position and hence the laser spots 38 are scanned over link positions along an axis in a first travel direction 52 , moved to a different row 16 or column 18 , and then scanned over link positions along an axis in a second travel direction 54 . Skilled persons will appreciate that scanning may include moving the workpiece 12 , moving the laser spot 38 , or moving the workpiece 12 and the laser spot 38 .
Traditional positioning systems are characterized by X-Y translation tables in which the workpiece 12 is secured to an upper stage that moves along a first axis and is supported by a lower stage that moves along a second axis that is perpendicular to the first axis. Such systems typically move the workpiece relative to a fixed beam position or laser spot 38 and are commonly referred to as stacked stage positioning systems because the lower stage supports the inertial mass of the upper stage which supports workpiece 12 . These positioning systems have excellent positioning accuracy because interferometers are typically used along each axis to determine the absolute position of each stage. This level of accuracy is preferred for link processing because the laser spot size 40 is typically only a little bigger than link width 28 , so even a small discrepancy between the position of laser spot 38 and link 22 can result in incomplete link severing. In addition, the high density of features on semiconductor wafers results in small positioning errors potentially causing laser damage to nearby structures. Stacked stage positioning systems are, however, relatively slow because the starting, stopping, and change of direction of the inertial mass of the stages increase the time required for the laser tool to process all the designated links 22 on workpiece 12 .
In split-axis positioning systems, the upper stage is not supported by, and moves independently from, the lower stage and the workpiece is carried on a first axis or stage while the tool, such as a fixed reflecting mirror and focusing lens, is carried on the second axis or stage. Split-axis positioning systems are becoming advantageous as the overall size and weight of workpieces 12 increase, utilizing longer and hence more massive stages.
More recently, planar positioning systems have been employed in which the workpiece is carried on a single stage that is movable by two or more actuators while the tool remains in a substantially fixed position. These systems translate the workpiece in two dimensions by coordinating the efforts of the actuators. Some planar positioning systems may also be capable of rotating the workpiece.
Semiconductor Link processing (“SLP”) systems built by Electro Scientific Industries, Inc. (“ESI”) of Portland, Oreg. employ on-the-fly (“OTF”) link processing to achieve both accuracy and high throughput. During OTF processing, the laser beam is pulsed as a linear stage beam positioner passes designated links 12 under the beam position. The stage typically moves along a single axis at a time and does not stop at each link position. The on-axis position of beam spot 38 in the direction travel 52 does not have to be accurately controlled; rather, its position is accurately sensed to trigger laser spot 38 to hit link 22 accurately.
In contrast and with reference again to FIG. 3, the position of beam spot 38 along cross-axes 56 or 58 is controlled within specified accuracy as the beam positioner passes over each link 22 . Due to the inertial mass of the stage or stages, a set-up move to start an OTF run produces ringing in the cross-axis position, and the first link 22 in an OTF run cannot be processed until the cross-axis position has settled properly. The settling delay or setting distance 60 reduces processing throughput. Without a settling delay (or, equivalently, a buffer zone of settling distance 60 ) inserted before the first laser pulse, several links 22 would be processed with serious cross-axis errors.
Although OTF speed has been improved by accelerating over gaps in the link runs, one limiting factor on the effectiveness of this “gap profiling” is still the requirement for the cross axis to settle within its specified accuracy. At the same time, feature sizes, such as link length 30 and link pitch 32 , are continuing to decrease, causing the need for dimensional precision to increase. Efforts to further increase the performance of the stage or stages substantially increase the costs of the positioning system.
The traditional way to provide for two-axis deflection of a laser beam employs a high-speed short-movement positioner (“fast positioner”) 62 , such as a pair of galvanometer driven mirrors 64 and 66 shown in FIG. 4 . FIG. 4 is a simplified depiction of a galvanometer-driven X-axis mirror 64 and a galvanometer-driven Y-axis mirror 66 positioned along an optical path 70 between a fixed mirror 72 and focusing optics 78 . Each galvanometer-driven mirror deflects the laser beam along a single axis. U.S. Pat. No. 4,532,402 of Overbeck discloses a stacked stage beam positioning system that employs such a fast positioner, and U.S. Pat. Nos. 5,751,585 and 5,847,960 of Cutler et al. disclose split-axis beam positioning systems in which the upper stage(s) carry at least one fast positioner. Systems employing such fast positioners are used for nonlink blowing processes, such as via drilling, because they cannot currently deliver the beam as accurately as “fixed” laser head positioners.
The split-axis nature of such positioners may introduce rotational Abbe errors, and the galvanometers may introduce additional positioning errors. In addition, because there must be separation between the two galvanometer-controlled mirrors, the mirrors cannot both be located near the entrance pupil to the focusing optics. This separation results in an offset of the beam that can degrade the quality of the focused spot. Moreover, two-mirror configurations constrain the entrance pupil to be displaced farther from the focusing optics, resulting in an increased complexity and limited numerical aperture of the focusing optics, therefore limiting the smallest achievable spot size. Even assuming such positioners could be used for link-severing, the above-described spot quality degradation would cause poor quality link-severing or incomplete link-severing and result in low open resistance across severed links 22 .
What is still needed, therefore, is a system and method for achieving higher link-processing throughput while maintaining focused spot quality.
SUMMARY OF THE INVENTION
An object of the invention is, therefore, to provide a system and/or method for achieving higher link-processing throughput while maintaining focused spot quality.
Another object of the invention is to employ a two-axis steering mirror to correct for linear stage settling errors.
Yet another object of the invention is to provide a positioner system employing coordinated motion for semiconductor link processing applications.
This invention preferably employs a two-axis steering mirror, pivotally mounted at the entrance pupil of the focusing lens, to perform small-angle motions that deflect the laser beam enough to compensate for cross-axis settling errors on the order of tens of microns. Although the settling errors occur in both axes, one embodiment of this invention is concerned primarily with correcting settling errors in a cross-axis direction to the OTF direction of linear stage travel. A two-axis steering mirror is employed for these corrections because either axis of the linear stage may be used as the OTF axis. The beam steering mirror is preferably used for error correction only and does not require coordination with or modification of the linear stage position commands, although such coordination is possible.
At least three technologies can be used to tilt a mirror in two axes about a single pivot point. These technologies include fast steering mirrors (“FSMs”) that employ a flexure mechanism and voice coil actuators to tilt the mirror, piezoelectric actuators that rely upon deformation of piezoelectric materials to tilt a mirror, and deformable mirrors that employ piezoelectric or electrostrictive actuators to deform the surface of the mirror. Piezoelectric actuators are preferred.
Advantages of the invention include the elimination of cross-axis settling time, resulting in increased throughput particularly for SLP systems. The invention also facilitates improved manufacturability of the main positioning stage(s) due to relaxed servo performance requirements because the steering mirror can correct for linear stage errors.
Additional objects and advantages of this invention will be apparent from the following detailed description of preferred embodiments thereof which proceed with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a portion of a DRAM showing the redundant layout of and programmable links in a spare row of generic circuit cells.
FIG. 2A is a fragmentary cross-sectional side view of a conventional, large semiconductor link structure receiving a laser pulse characterized by prior art pulse parameters.
FIG. 2B is a fragmentary top view of the link structure and the laser pulse of FIG. 2A, together with an adjacent circuit structure.
FIG. 2C is a fragmentary cross-sectional side view of the link structure of FIG. 2B after the link is removed by the prior art laser pulse.
FIG. 3 is a plan view of a prior art beam travel path.
FIG. 4 is a simplified side view of a prior art fast positioner employing a pair of galvanometer-driven mirrors that deflect the laser beam along different respective single axes.
FIG. 5 schematically illustrates a side sectional view of a preferred two-axis mirror employed in the practice of the invention.
FIG. 6 schematically illustrates a partial front view of a preferred two-axis mirror employed in the practice of the invention.
FIG. 7 illustrates the effect of the steering mirror during the OTF run.
FIG. 8 illustrates an exemplary multi-row, cross-axis dithering (“MRCAD”) work path.
FIG. 9 is a side sectional view of a representative two-axis steering mirror.
FIG. 10 is a simplified plan view of a representative two-axis steering mirror.
FIG. 11 is a simplified schematic block diagram of an exemplary positioner control system for coordinating the stage positioning and the steering mirror for error correction.
FIG. 12 is a simplified schematic block diagram of an exemplary positioner control system for coordinating the stage positioning and the steering mirror for beam-to-work scans and error correction.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
One embodiment of a representative beam positioning system is described in detail in U.S. Pat. No. 4,532,402 of Overbeck, which is assigned to the assignee of this application. A preferred X-Y stage is a “Dynamix” model available from Newport Corporation of Irvine, Calif.
The beam positioning system preferably employs a laser controller that controls a stacked, split-axis, or planar positioner system and coordinates with reflectors to target and focus laser system output to a desired laser link 22 on IC device or workpiece 12 . The beam positioning system permits quick movement between links 22 on the same or different workpieces 12 to effect unique link-severing operations based on provided test or design data. The beam positioning system may alternatively or additionally employ the improvements, beam positioners, or coordinated motion schemes described in U.S. Pat. Nos. 5,751,585, 5,798,927, and 5,847,960 of Cutler et al., which are assigned to the assignee of this application. Other fixed head or linear motor driven conventional positioning systems could also be employed, as well as the systems employed in the 9000, 9800, and 1225 model series manufactured by ESI of Portland, Oreg., the assignee of this application.
With reference to FIGS. 5 and 6 and with respect to this invention, the final turn mirror of a fixed head system or alternatively fast positioner 66 (FIG. 4) is preferably replaced by a single high-speed, high-accuracy two-axis steering mirror system 100 that includes a mirror 102 capable of actuation with at least two degrees of freedom. Mirror 102 has a centrally positioned pivot point 104 that preferably coincides with an entrance pupil 106 of a focusing lens 108 . Two-axis steering mirror system 100 is preferably used for error correction, although it may be employed for beam steering because either axis of the linear stage maybe used as the OTF axis.
Because the beam is focused to a very fine spot size for SLP applications, the mechanism directing mirror system 100 preferably pivots the mirror 102 along at least two axes about pivot point 104 , which is located at or near the entrance pupil of focusing optics or lens 108 . Small angle perturbations in the position of mirror 102 deflect the beam enough to correct for linear stage settling errors at the work surface, and because mirror 102 is located at or near the entrance pupil of focusing lens 108 , the beam is shifted without distorting the focused spot, allowing delivery of a small, high quality spot.
In one embodiment, settling errors in a cross-axis direction 110 are corrected by mirror 102 , while motion in an on-axis direction 112 is not corrected. This single axis correction allows the linear stage interferometer feedback to be the sole source of laser pulse triggering. However, with proper coordination, on-axis direction 112 steering mirror 102 motion is possible, although it complicates the design and introduces additional error sources that can degrade on-axis direction 112 accuracy if such errors are not addressed.
Motion in each axis of mirror 102 exhibits scale factor and offset errors, noise, and cross-axis coupling. These error source can be well-controlled and calibrated out in the system, with noise and temperature stability effects controlled through conventional design techniques.
Calibration of mirror system 100 through beam-to-work (“BTW”) alignments can correct for any non-linearity and alignment errors in steering mirror 102 . Traditionally, the term beam-to-work is used as nomenclature for the process of scanning the linear stage back and forth, while directing the laser beam spot at low power at an alignment target on the wafer or workpiece 12 (FIG. 1 ). Optical measurements of the reflection off the target are used to precisely determine target and hence wafer location. By scanning several targets with BTW scans, the offset and rotation of the wafer relative to the beam spot can be ascertained. It is also possible to map out other effects such as axis orthogonality and positional distortions.
After mirror system 100 is added to the laser system, traditional BTW type scans can be used to map out any inaccuracies/nonlinearities in steering mirror 102 response. This is accomplished by doing a BTW scan with mirror 102 in the nominal zero offset (in either axis) position. Then mirror 102 is tilted, and another BTW scan is performed to determine how much lateral offset of the laser beam spot is imparted by the tilt. By measuring the offset caused by numerous mirror tilts in the U and V axes, mirror system 100 can be fully characterized.
Once the response of mirror system 100 is determined to sufficiently fine precision, then instead of moving the linear stage back and forth, it is possible to use mirror system 100 for subsequent BTW type alignment scans.
FIG. 7 illustrates the corrective effect of two-axis steering mirror system 100 during an OTF run. A linear stage ringing is represented by a ringing curve 120 . Mirror 102 deflects the laser beam in cross-axis direction 110 as represented by a correction curve 122 that is the inverse of ringing curve 120 . The resulting beam position is the sum of the linear stage motion and the deflected beam position and is represented by a resulting beam path curve 124 , which is free of cross-axis error.
FIG. 8 illustrates using steering mirror system 100 for MRCAD processing during boustrophedon or raster scanning in the context of link severing to further improve the speed at which links are blown. In a preferred mode of operation, MRCAD scanning is done in cross-axis direction 110 while moving along a row 130 of links 132 . MRCAD scanning employs steering mirror 102 (FIGS. 5 and 6) to direct the laser beam along a pathway 134 at links 132 and adjacent links 136 in adjacent rows 138 without needing to move the slower linear motion stage in cross-axis direction 110 . This is possible because not all the links in each row need to be blown. Link processing becomes far more efficient with MRCAD because the linear or stages do not have to be scanned or slewed down each row, so the total number of link row scans can be substantially reduced. As integration increases and link sizes, spot sizes, and pitch distance decrease, MRCAD scanning will become an even more valuable technique.
In another mode, supplemental on-axis dithering (“SOAD”) uses mirror 102 to deflect the beam in on-axis direction 112 (FIGS. 5 - 7 ). In this operational mode, the beam can be quickly directed ahead in on-axis direction 112 , severing links while the linear motion stage catches up. The SOAD scan ahead or scan behind the stage feature allows the positioning system to reduce stage velocity changes or to sever several links during a single slowed movement segment.
At least three technologies can be employed to tilt mirror 102 in two axes about pivot point 104 . These technologies include FSMs that employ a flexure mechanism and voice coil actuators, piezoelectric actuators that rely upon deformation of piezoelectric materials, and piezoelectric or electrostrictive actuators to deform the surface of a mirror. Suitable voice coil actuated FSMs are available from Ball Aerospace Corporation of Broomfield, Colo. and Newport Corporation of Irvine, Calif. However, the preferred actuator is a model S-330 Ultra-Fast Piezo Tip/Tilt Platform manufactured by Physik Instrumente (“PI”) GmbH & Co. of Karlsruhe, Germany.
Traditional galvanometers are not typically used for this application because they each tilt a mirror about only one axis and ordinarily have insufficient positioning accuracy. Moreover, a pair of physically separated galvanometer mirrors is required for two axes of actuation. This separation is incompatible with the desire that actuation occur about one pivot point located near the entrance pupil of focusing lens 108 (FIGS. 5 and 6) to maintain a high quality laser spot at the surface of workpiece 12 . Nevertheless, it is possible to employ galvanometer deflected mirrors in this invention, particularly if employed in single-axis and small deflection applications to maintain accuracy and well focused laser spots.
By way of example only, FIGS. 9 and 10 show an FSM two-axis mirror system 200 in which four electrical to mechanical vibration generators or transducers are supported by a transducer support platform 220 in a quadrature relationship, whereby transducers 222 , 224 , 226 , and 228 are positioned at 0, 90, 180, and 270 degrees with respect to a central axis 230 ; therefore, adjacent ones of the transducers are set at right angles with respect to each other. A movable mirror support member 232 has a central portion or hub 234 bearing a mirror or reflective surface 236 centered with respect to axis 230 . Mirror 236 has a diameter of about 30 mm or less to reduce its weight and facilitate high frequency response for desired beam correction. Mirror 236 is coated with conventional laser optical coatings to account for laser wavelength or design parameters.
Four lightweight rigid struts or elongated members 242 , 244 , 246 , and 248 extend radially from hub 234 of mirror support member 232 , and have respective peripheral terminal portions 252 , 254 , 256 , and 258 affixed to respective transducers 222 , 224 , 226 , and 228 , which are electrically movable voice coils. For a further description of a suitable conventional voice coil/loudspeaker arrangement, see Van Nostrand's Scientific Encyclopedia, Sixth Edition, page 1786. The use of such conventional loudspeaker coils for the transducers to perform mechanical actuation, decreases the manufacturing cost of the apparatus. The floating mirror support 232 can beneficially be made of a lightweight material, such as metal (e.g. aluminum or beryllium) or plastic, enabling rapid response to the electrical input signals to the voice coils to be described.
A tip control generator 260 is connected to transducers 224 and 228 to cause them to move in a complementary “push pull” relationship with each other. Similarly, a tilt control generator 262 is connected to transducers 222 and 226 to cause these coils to also move in a complementary push pull relationship with each other. A laser beam 270 is reflected off reflective surface 236 and a reflected beam 272 is positioned by the generators controlling the cross axis, which is perpendicular to OTF direction of travel, to compensate for cross axis errors. The pairs of signals produced by each generator assume a push-pull relationship, so that when transducer 222 is pulling upper terminal portion 252 of support member 232 to the right in FIG. 10 , lower transducer 226 is pushing terminal portion 256 to the left, to tilt reflective surface 236 , thereby deflecting reflected beam 272 . The actuation can be alternated at the beginning of an OTF run, for example, to move reflective surface 236 at a proper frequency and damped amplitude to compensate for linear stage ringing in cross-axis direction 110 , thereby eliminating the negative effects of linear stage settling time and producing a relatively straight beam path. Thus, links that would otherwise be in the conventional buffer zone can be processed accurately.
Mirror systems suitable for use with this invention can be implemented with a large enough field to do MRCAD scans by providing beam deflection in a range of about 50 to 100 microns; however, such mirror systems can also be implemented for cross-axis correction only by providing beam deflection in a range of about 10 to 50 microns or as little as about 10 to 20 microns. The mirror is preferably positioned within about plus or minus 1 mm of the entrance pupil of the focusing lens. These ranges are exemplary only and can be modified to suit the system design and particular link processing applications.
The preferred model S-330 Tip/Tilt Platform manufactured by PI uses piezoelectric actuators for high speed, two-dimensional mirror tilting. Strain gage sensors accurately determine mirror position and provide feedback signals to the control electronics and drive circuitry. A more complete description of the model S-330 Tip/Tilt Platform is available at the PI web site, www.physikinstrumente.com.
The main advantages of the PI Piezo Tip/Tilt Platform are that the device is commercially available and has a very compact size that readily mounts in an ESI model 9820 positioning system.
Disadvantages of the PI Piezo Tip/Tilt Platform are that it has insufficient beam deflection range for use in beam-to-work scanning applications even though its range is sufficient for error correction applications; and nonlinear motion, thermal drive, hysteresis, and high-voltage actuation are all inherent problems with piezoelectric actuation that have to be accounted for.
Of course, other vendors or other types of mirror or actuator designs are suitable for use with this invention.
In addition to all the other above-described advantages, this invention permits a relaxation on the requirements for the linear motors (jerk time, settling time) using the secondary system to correct for errors. This substantially reduces the cost of the linear motors and also reduces the dependency of the system throughput on the acceleration limit of the linear stage or stages.
FIG. 11 shows an embodiment of a positioner control system 300 of this invention for coordinating the positioning of X- and Y-axis motion stages 302 and 304 , and also the positioning of a two-axis steering mirror 306 for positioning error correction. Of course, motion stages 302 and 304 may be combined into a single planar motion stage having positioning control in the X- and Y-axis directions. In a standard operational mode, two-axis steering mirror 306 is used to correct positioning errors caused by X- and Y-axis motion stages 302 and 304 .
A position command generator 308 generates X- and Y-axis position command signals for delivery through summing junctions 310 and 312 to X- and Y-axis motion controllers 314 and 316 to respective X- and Y-axis motion stages 302 and 304 . The actual positions of X- and Y-axis motion stages 302 and 304 are sensed by respective X- and Y-axis position sensors 318 and 320 and signals representing the actual positions are conveyed to adders or summing junctions 310 and 312 to generate X- and Y-axis position error signals. X- and Y-axis motion controllers 314 and 316 receive the error signals and act to minimize any errors between the commanded and actual positions. For high-accuracy applications, X- and Y-axis position sensors 318 and 320 are preferably interferometers.
Residual error signals, such as those generated by ringing, are conveyed through enabling gates 322 and 324 to a coordinate transformation generator 326 , which may be optional depending on whether motion stages 302 and 304 share a common coordinate system with two-axis steering mirror 306 . In either event, the residual error signals are passed through adders or summing junctions 328 and 330 to U- and V-axis steering mirror controllers 332 and 334 , which act to tip and/or tilt steering mirror 306 by controlled amounts to deflect, for example, laser beam 270 (FIG. 9) to correct for positioning errors of X- and Y-axis motion stages 302 and 304 . The actual tip and/or tilt positions of two-axis steering mirror 306 are sensed by respective tip and tilt sensors 336 and 338 and signals representing the actual tip and tilt positions are conveyed to adders or summing junctions 328 and 330 to generate tip and tilt position error signals. U- and V-axis steering mirror controllers 332 and 334 receive the error signals and act to correct any errors between the commanded and actual positions. For high-accuracy applications, two-axis steering mirror 306 is preferably a piezoelectric tilt/tip platform, and position sensors 318 and 320 are preferably strain gages. Suitable alternative sensors may include optical, capacitive, and inductive sensing techniques. In this embodiment, skilled workers will understand that U- and V-axis steering mirror controllers 332 and 334 should be adapted to provide zero to 100 volt drive signals to the piezoelectric actuators deflecting two-axis steering mirror 306 .
Enabling gates 322 and 324 implement a provision in which position command generator 308 can selectively disable position error correction for either the X or the Y axis, thereby enabling error correction for the cross-axis while leaving the on-axis unaffected, or vice versa.
FIG. 12 shows an embodiment of a positioner control system 340 for coordinating the positioning of X- and Y-axis motions stages 302 and 304 and, in this embodiment, FSM 236 (FIGS. 9 and 10) for MRCAD scans and positioning error correction. In an extended operational mode, the steering mirror is used for error correction and MRCAD scanning. In this mode of operation, a position command generator 342 generates X- and Y-axis positioning commands for X- and Y-axis motion stages 302 and 304 and also U- and V-axis tip and tilt commands for deflecting FSM 236 . Summing junctions 328 and 330 generate the positioning command for FSM 236 as the sum of the error signals from X- and Y-axis motion stages 302 and 304 and, in this embodiment, also the U- and V-axis tip and tilt commands.
The error signals are generated in the same manner as in the standard error correction mode. The additional U- and V-axis tip and tilt commands are produced by position command generator 342 to accomplish the desired beam-to-work scanning. Because beam-to-work and MRCAD applications typically require wider ranges of mirror deflection, this embodiment of the invention preferably employs voice coil actuated FSM two-axis mirror system 200 .
In typical operation, the position commands for MRCAD scanning are used to produce cross-axis motion of the laser beam without commanding cross-axis motion of the motion stages. However, other applications are envisioned that would benefit from on-axis supplemental dithering to boustrophedon scanning.
The control schemes depicted in these figures are intended to illustrate the basic implementation and operation of this invention. More advanced control schemes, such as those employing feedforward commands to the motion stages and steering mirror, will be obvious to those skilled in the art.
Skilled workers will appreciate that the two-axis steering mirror systems of this invention can be adapted for use in etched-circuit board via drilling, micro-machining, and laser trimming applications as well as for link severing.
It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiment of this invention without departing from the underlying principles thereof. The scope of this invention should, therefore, be determined only by the following claims. | Laser beam positioners ( 300, 340 ) employ a steering mirror ( 236, 306 ) that performs small-angle deflection of a laser beam ( 270 ) to compensate for cross-axis ( 110 ) settling errors of a positioner stage ( 302 ). A two-axis mirror is preferred because either axis of the positioner stages may be used for performing work. In one embodiment, the steering mirror is used for error correction only without necessarily requiring coordination with the positioner stage position commands. A fast steering mirror employing a flexure mechanism and piezoelectric actuators to tip and tilt the mirror is preferred in semiconductor link processing (“SLP”) applications. This invention compensates for cross-axis settling time, resulting in increased SLP system throughput and accuracy while simplifying complexity of the positioner stages because the steering mirror corrections relax the positioner stage servo driving requirements. | 1 |
RELATED APPLICATIONS
[0001] This application is a continuation-in-part of copending U.S. patent application Ser. No. 14/038,424 entitled “Recovering and Recycling Uranium Used for Production of Molybdenum-99,” filed Sep. 26, 2013, incorporated by reference herein.
STATEMENT REGARDING FEDERAL RIGHTS
[0002] This invention was made with government support under Contract No. DE-AC52-06NA25396 awarded by the U.S. Department of Energy. The government has certain rights in the invention.
FIELD OF THE INVENTION
[0003] The present invention relates generally to the recovery of uranium from an irradiated solid target and more particularly to the recovery and purification of uranium from an irradiated solid target after removal of molybdenum-99 produced from the target.
BACKGROUND OF THE INVENTION
[0004] Technetium-99m (“Tc-99m”) is the most commonly used radioisotope in nuclear medicine. Tc-99m is used in approximately two-thirds of all imaging procedures performed in the United States. Tens of millions of diagnostic procedures using Tc-99m are undertaken annually. Tc-99m is a daughter isotope produced from the radioactive decay of molybdenum-99 (“Mo-99”). Mo-99 decays to Tc-99m with a half life of 66 hours.
[0005] The vast majority of Mo-99 used in nuclear medicine in the U.S. is produced in aging foreign reactors. Many of these reactors still use solid highly enriched uranium (“HEU”) targets to produce the Mo-99. HEU has a concentration of uranium-235 (“U-235”) of greater than 20%. Maintenance and repair shutdowns of these reactors have disrupted the supply of
[0006] Mo-99 to the U.S. and to most of the rest of the world. The relatively short half-life of the parent radioisotope Mo-99 prohibits the build-up of reserves. One of the major producers, The National Research Reactor in Canada, will cease production in 2016.
[0007] An alternative strategy for providing Mo-99 is based upon the use of low enriched uranium (LEU), which presents a much lower nuclear proliferation risk than HEU. LEU has a concentration of U-235 of less than 20%, and many international Mo-99 producers are converting from HEU to LEU solid targets for Mo-99 production.
[0008] Several of the technologies currently being considered for the domestic supply of Mo-99 are based on the fission of U-235 in LEU. In all processes being considered, only a small fraction of the U-235 present in the irradiated target will be consumed during irradiation. Fission of U-235 generates a variety of fission products, one of which is Mo-99.
[0009] Some form of enriched uranium (HEU and/or LEU) is used for the production of Mo-99. After the fission process, the remaining uranium is typically discarded along with other fission products as waste. Recovery and purification of the uranium would make it available for reuse, storage, or disposal.
[0010] Therefore, an object of the present invention is to provide a process for recovering, and purifying, uranium from an irradiated solid target after separating Mo-99 produced from the irradiated target.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 provides a flow diagram of an embodiment process for recovery and purification of uranium from an irradiated solid target after separating Mo-99 produced from the irradiated target.
SUMMARY OF THE INVENTION
[0012] The embodiments for recovering uranium apply to recovering all isotopic ratios of uranium, including low-enriched uranium (LEU) as well as highly-enriched uranium (HEU). Enriched uranium refers to uranium enriched in isotope U-235.
[0013] An embodiment relates to a process for recovering uranium from an irradiated solid target, after recovering Mo-99 produced from the irradiated target. The process includes irradiating a solid target comprising uranium to produce fission products comprising Mo-99, and thereafter dissolving the target. Following dissolution, the solution is conditioned to provide an aqueous nitric acidic solution comprising a first acid concentration and a first uranium concentration. The uranium in the acidic solution will be in the +VI oxidation state and in the chemical form of the uranyl di-oxo di-cation (UO 2 2+ ). The acidic solution, along with the uranium, will pass through a solid sorbent, while Mo-99 is removed from the solution, remaining adsorbed to the sorbent. The Mo-99 will be recovered in a subsequent desorption step. After passing through the sorbent, the concentration of acid and uranium in the acidic uranium solution is adjusted to concentrations suitable for crystallization of uranyl nitrate hydrates. After inducing this crystallization of uranyl nitrate hydrates, the uranium contained in the uranyl nitrate hydrates is separated from a supernatant which contains soluble fission products. Thus the uranium is recovered and purified during this process, and is available for reuse, storage, or disposal.
[0014] The embodiment process for recovering uranium applies to recovering all isotopic ratios of uranium including LEU as well as HEU. Enriched uranium refers to uranium enriched in isotope U-235.
DETAILED DESCRIPTION
[0015] An embodiment process relates to recovery of uranium that has been used for the production of Mo-99 generated from the fission of U-235. Mo-99 undergoes radioactive decay to Tc-99m, the most widely used radioisotope in nuclear medicine. Recovery and purification of uranium allows for its reuse, storage, or disposal.
[0016] It should be understood that uranium includes both LEU (uranium having less than 20% of the U-235 isotope), and also HEU (uranium having greater than 20% of the U-235 isotope). Thus, an embodiment of the disclosed process may be used for recovery of either LEU or HEU.
[0017] An embodiment relates to a process for recovering uranium from a solid target that has been used for the production of Mo-99. The process employs a sorbent-based separation. The sorbent is used to remove Mo-99 prior to recovery and purification of the uranium. The process begins with irradiation of a solid target having fissionable uranium (i.e., U-235). The irradiation promotes fission of the U-235 to form fission products that include Mo-99.
[0018] After the irradiation the solid target is dissolved. The resultant solution is conditioned to provide an aqueous nitric acid solution of from about 0.01 M to about 2 M (M means moles of nitric acid per liter of solution). The uranium concentration of this solution is from about 50 gU/L to about 350 gU/L (gU/L means grams of uranium per liter of solution). The acidic solution, along with the uranium, will pass through a solid sorbent (e.g., a titania-based sorbent or an alumina-based sorbent), while Mo-99 is removed from the solution, remaining adsorbed to the sorbent. The Mo-99 will be recovered in a subsequent desorption step (e.g., washing the sorbent with an alkaline solution to strip the Mo-99 from the sorbent). The sorbent may be packed into a column, with processing solutions then flowing through the column.
[0019] After passing through the sorbent, and removal of the majority of the Mo-99, the aqueous nitric acid solution of from about 0.01 M to about 2 M, containing a uranium concentration of from about 50 gU/L to about 350 gU/L, is evaporated under vacuum and/or through heating. The resultant solution is acidified with a suitable amount of nitric acid, and water if needed, to yield a solution concentration of nitric acid of from about 4M to about 8M, and a uranium concentration of from about 350 gU/L to about 650 gU/L. The temperature of this solution may be raised to ensure that all the uranium remains in solution. This solution is then evaporated under reduced pressure and/or cooled in order to promote conditions suitable for the formation of crystals of uranyl nitrate hydrates from the solution. An example of such a uranyl nitrate hydrate is UO 2 (NO 3 ) 2 .6H 2 O. The crystals are then separated from the supernatant that remains and can be washed with nitric acid.
[0020] Most of the uranium from any solid uranium target suitable for the production of Mo-99 that can be dissolved, and then converted into a solution containing aqueous nitric acid of concentration from about 0.01 M to about 2 M and uranium of concentration from about 50 gU/L to about 350 gU/L, can be recovered using this crystallization process. Examples of suitable solid uranium targets include, but are not limited to, uranium metal foils, U 3 Si 2 plates, UAl x targets and UO 2 targets. Through dissolution and subsequent chemical processing of the solid targets, a solution of irradiated uranium (50-350 gU/L) in nitric acid (0.01-2 M) can be prepared for recovery of Mo-99. After recovery of the majority of the Mo-99 using a sorbent, the remaining solution can be conditioned for crystallization of uranyl nitrate hydrates. Crystallization of uranyl nitrate hydrates removes most of the uranium from solution. The crystals can be filtered or otherwise removed from the supernatant and washed with nitric acid.
[0021] Only a small fraction of the U-235 component of the uranium undergoes fission during irradiation. Removal of the Mo-99 along with other fission products with the sorbent separation process provides a uranium-containing solution having a greatly reduced amount of fission products. Additionally, many fission products will remain soluble during uranium nitrate hydrates crystallization; including Ba-140, Zr-95, Ru-103 and Ce-141, and these fission products will thus be separated from uranium nitrate hydrates. Therefore, according to the present process, recovery of such a purified uranium product, as uranium nitrate hydrates, affords uranium for reuse, storage, or disposal. In the case of disposal, purification of the uranium nitrate hydrates reduces the hazardous nature of any eventual uranium waste form.
[0022] Nitric acid that is used in the process may also be recovered. Thus, nitric acid can also be recycled, further minimizing hazardous waste.
[0000] An embodiment process will allow (1) recovery of Mo-99 using a sorbent and (2) recovery of purified uranium from the irradiated target for reuse, storage, or disposal.
[0023] The concentrations of fission products and other impurities in the crystallized uranium nitrate hydrates may be too high for reuse, storage, or disposal. In this case further purification of the uranium nitrate hydrates crystalline material can be undertaken. Additional purification can be accomplished by a number methods including washing the crystals with nitric acid, heating the crystals to sweat out impurities prior to washing, and/or undertaking a second recrystallization process. In the latter case the uranyl nitrate hydrates solid would be dissolved in nitric acid, and the resulting solution would be conditioned to yield a 350-650 gU/L solution in a nitric acid concentration of between 4-8 M prior to crystallization through concentration by evaporation under reduced pressure and/or by cooling.
[0024] 80% or greater of the Mo-99 produced from the U-235 fission in a solid uranium target (not corrected for radioactive decay) may be recovered after a sorbent-based separation, and 93% or greater of the uranium may be recovered in a purified form.
[0025] After the solid target irradiation and dissolution, a crude Mo-99 product is separated from the uranium using a sorbent. Additional purification steps on the crude Mo-99 will result in a pure Mo-99 product for use in Tc-99m generators. In an embodiment, a solution of uranium in nitric acid may be concentrated through evaporation and acidified to a concentration of nitric acid of between 4 M and 8 M and uranium in an amount of, for example, 500 gU/L. Cooling to a temperature effective for crystallization, forming crystals of uranyl nitrate hydrates, an effective temperature being a temperature of from about 10° C. to about −30 ° C. (e.g., −10° C.) allows crystallization of 93% or greater of the uranium as uranyl nitrate hydrates, which is a largely insoluble salt at such cold temperatures. Evaporation under reduced pressure may be used as a means of both cooling the solution and lowering solution volume to increase the percentage of uranyl nitrate hydrates crystallized from solution. The crystals of uranyl nitrate hydrates are filtered from the supernatant that remains.
[0026] An inorganic oxidant may be added to the solution of irradiated uranium (50-350 gU/L) in nitric acid (0.01-2 M) to ensure all of the Mo-99 is in the +VI oxidation state. +VI is the preferred oxidation state for the separation of Mo-99 from the uranium in nitric acid, in the sorbent separation step. Suitable inorganic oxidants include potassium permanganate, oxalic acid, hydrogen peroxide, and sodium persulfate.
[0027] In another embodiment, a uranium solution could be irradiated instead of a solid target to generate Mo-99. In this case the solution containing irradiated uranium can be conditioned to produce a solution of uranium (50-350 gU/L) in nitric acid (0.01-2 M) suitable for sorbent recovery of Mo-99. After recovery of the majority of the Mo-99 using a sorbent, the remaining solution can be conditioned for crystallization of uranyl nitrate hydrates. The purified uranium nitrate hydrates from the irradiated uranium solution is then available for reuse, storage, or disposal.
[0028] FIG. 1 provides a flow diagram for an embodiment process. The boxes refer to a particular material and the numbers 1 through 5 , which are in between boxes refer to process steps. Thus, the topmost box refers to an irradiated solid target of enriched uranium. After target irradiation, step 1 refers to the irradiated uranium target dissolution, and conditioning to form an aqueous nitric acid solution having a concentration of from about 0.01 M to about 2 M (e.g., 0.5 M). The concentration of uranium would be from about 50 gU/L to about 350 gU/L. Next, process step 2 involves removal of greater than 80% of the Mo-99 (not corrected for radioactive decay) from the solution using a solid sorbent-based separation process. >98% of the uranium remains in the nitric solution and is subjected to process step 3 . Process step 3 involves conditioning the solution by increasing the concentration of uranium nitrate to a concentration of from about 350 gU/L to about 650 gU/L and increasing the concentration of nitric acid to a concentration of from about 4 M to about 8 M. These results may be achieved by evaporation using heat and/or evaporation under a reduced pressure and addition of nitric acid. This solution may be held at above ambient temperature (e.g., 40° C.) to be sure all of the uranium is dissolved. Process step 4 is performed on the now more concentrated solution, and results in crystallization to form crystals of uranyl nitrate hydrates, and a supernatant. The uranyl nitrate hydrates contain greater than 93% of the uranium. The supernatant contains less than 7% of the uranium which can be subsequently recovered, if required. Process step 5 results in uranium for reuse, storage, or disposal.
[0029] The aforementioned embodiments relate to the irradiation of solutions of uranium and subsequent recovery of Mo-99 for generating Tc-99m, and thus relate to satisfying an objective of using LEU for generating Mo-99 and subsequent reuse, disposal, or storage of the LEU.
[0030] Although the present invention has been described with reference to specific details, it is not intended that such details should be regarded as limitations upon the scope of the invention, except as and to the extent that they are included in the accompanying claims. | A process for minimizing waste and maximizing utilization of uranium involves recovering uranium from an irradiated solid target after separating the medical isotope product, molybdenum-99, produced from the irradiated target. The process includes irradiating a solid target comprising uranium to produce fission products comprising molybdenum-99, and thereafter dissolving the target and conditioning the solution to prepare an aqueous nitric acid solution containing irradiated uranium. The acidic solution is then contacted with a solid sorbent whereby molybdenum-99 remains adsorbed to the sorbent for subsequent recovery. The uranium passes through the sorbent. The concentrations of acid and uranium are then adjusted to concentrations suitable for crystallization of uranyl nitrate hydrates. After inducing the crystallization, the uranyl nitrate hydrates are separated from a supernatant. The process results in the purification of uranyl nitrate hydrates from fission products and other contaminants. The uranium is therefore available for reuse, storage, or disposal. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a process for harvesting, packing, cooling and subsequently transporting fresh produce, and more particularly, to a process which does not require shipping containers to be coated or impregnated with a wax compound. The present invention provides a cold, wet environment without a fresh produce container, rather than having the container held in a wet, cold environment.
Many methods are in use today for harvesting, packing, cooling and transporting produce. Typically produce is picked from fields when the ambient temperature is above 60° and oftentimes much hotter, such as in the 80s and 90s. Once the product is picked, it must be quickly packaged and often transported over long distances with a significant time period until ultimate marketing. It is a requirement that the produce be cooled and remain in a cooled state throughout the transportation process. Cooling is done to retard degradation of the product, the ultimate consumer, of course wishing to purchase fresh, wholesome produce. Typical cooling processes include hydrocooling, vacuum cooling, icing and forced air refrigeration. A typical state-of-the-art process for harvesting and packing broccoli, and the like would include having a ready supply of wax-impregnated shipping containers (produced from corrugated paperboard) in the field and as the broccoli is harvested, it is immediately placed in a shipping container. Thereafter the containers are iced, meaning the open volume within the packed container is filled with ice. These iced containers are then palletized and refrigerated to maintain the temperature of the fresh produce within a range of from approximately 32°-34° F. What occurs here is that as the relatively warm produce gives up its heat a fair amount of free water is formed by the melting ice. It is for this reason that in the past shipping containers made from corrugated paperboard necessarily had to be made moisture resistant, typically by saturating them with wax.
Another example is the picking, packaging and shipping of celery which usually is cooled using cold water. Large amounts of cold water are cascaded over the celery stalks after they are placed in wax-impregnated shipping containers.
Not only were these processes undesirable from the standpoint of utilizing large amounts of ice (which simply adds to shipping weight) or cold water, but they also resulted in a wax-impregnated shipping container at the receiving end which had to be disposed of properly after the shipment and use. Today as more and more shipping containers and other paper products are being recycled, it becomes essential to have paper containers that are in fact recyclable without difficulty. The fact that shipping containers contained wax made those containers difficult, if not impossible, to send through a repulping-recycling process. It has thus become highly desirable to utilize nonwax-impregnated shipping container material in the packaging and transport of fresh produce. The fundamental requirement, however, must still be met in that fresh produce as it is picked and packed and subsequently cooled must thereafter be maintained in a fresh and marketable condition. If a shipping container is utilized which does not have objectionable moisture resistant compounds, such as the wax, it cannot then be subjected to large amounts of moisture because the moisture will degradate the strength characteristics of the shipping container. It is of course critical to retain the strength characteristics as a plurality of packed shipping containers are normally stacked in palletized form prior to shipment. During shipment, unloading and distribution, the containers must maintain their structural rigidity. Therefore, when using nonwaxed containers, it becomes essential to eliminate the use of ice or large amounts of cooling water to cool the fresh produce after packing.
The present invention provides a packaging system whereby objectionable compounds such as wax can be eliminated from the shipping container and where ice or large volumes of cold water are not required for use in cooling. In addition, the pressent process utilizes a vacuum cooling step where the relatively high field temperatures are reduced down to an acceptable temperature range very quickly compared to some prior vacuum cooling steps utilized in known prior art processes.
Accordingly, from the foregoing, one object of the present invention is to eliminate the use of objectionable compounds within the shipping container so that the container is repulpable-recyclable.
Yet another object of the present invention is to reduce the overall time period for cooling selected fresh picked produce from its field temperature down to its desired transport temperature and to eliminate the use of heavy ice during transport.
Still a further object is to provide the appropriate environment for the product after packing and during shipment without reducing the performing strengths of the shipping container.
Yet another object of this invention is to provide a harvesting, packing, cooling and transport process for fresh produce which is cost effective and results in the arrival of harvest fresh product ready for consumption.
These and many additional objects will be better understood by reading the specification to follow in conjunction with the attached drawings.
SUMMARY OF THE INVENTION
Briefly stated the present invention is practiced by providing a corrugated paperboard shipping container without wax or other objectionable compounds therein and with sufficient stacking strength for palletizing with an open top. An open unvented, thin, flexible plastic bag is placed within the shipping container and thereafter it is filled with fresh picked produce in the field. Substantially simultaneously with the filling of the plastic bag sitting within the shipping container a predetermined amount of water is sprayed over the fresh picked and packed produce. Soon thereafter the tops of the unvented bags are folded and loosely closed. A plurality of thusly packed shipping containers are then palletized and loaded into a vacuum cooling chamber where the temperature of the produce is brought down to its temperature range for shipment and subsequently handling which will normally be within a range of 32°-34° F. Since the plastic bags are not completely sealed from the atmosphere, the free liquid sprayed onto the produce will begin to evaporate and effectly reduce the temperature of the produce down to its desired range. This method of cooling is well known. However, in utilizing the cooling method with the additional water sprayed over the produce and not the container, the temperature of the produce can be reduced in a relatively short period of time with minimum dehydration of the product. Once the vacuum chamber reduces the temperature of the produce to its shipping temperature, the palletized stacks of packaged produce will then be loaded into refrigerated containers for transportation to selected destinations. By maintaining the environment within the box, this packing, cooling and shipping process has been found to yield superior produce when being marketed which is still fresh and wholesome after transport and storage times well beyond that currently experienced.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a typical corrugated paperboard box and a flexible plastic bag above the box prior to insertion therein.
FIG. 2 is a representation in schematic form of the process forming the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, the typical corrugated paperboard shipping container suitable for use in the present invention is depicted generally at 10. Container 10 is typical in that it is composed of corrugated shipping container material which is a corrugated medium overlaid with two sheets of linerboard. Corrugated paperboard is produced in a well known in-line process and thereafter the corrugated paperboard material is cut, scored and folded to form containers with various structures. In some cases as the containers are folded into their erected configuration, they will be glued in order to hold their final shape.
Typically, when harvesting, packing and shipping fresh produce, corrugated paper packaging materials are often the material of choice for the container. Corrugated paperboard containers provided good containment at relatively low cost and by good containment it is meant holding the particular type of produce to provide optimum transport while retaining product freshness. In addition, corrugated paperboard does provide suitable stacking strength when a plurality of such packed containers are stacked one atop another, in palletized form, for shipment.
The structure of container 10 is known and is commonly used for shipping fresh produce such as cauliflower, broccoli, and the like. Typically, it is manufactured utilizing single wall corrugated board with a wax impregnant to make it substantially moisture proof. The wax compound was necessary to waterproof the corrugated paperboard since fresh produce contains significant amounts of water and ice or additional water was normally applied to the produce for cooling purposes, thereby allowing free water to contact the paperboard. Unless the paperboard material had been treated with a waterproofing agent, water would be readily absorbed into the board and the paperboard would deteriorate over time, causing the container to lose its strength and other properties. As pointed out in the background of the invention after the fresh produce is harvested and placed within the container, the produce must be cooled from its field temperature down to a temperature usually within a range of from about 32° F. to about 34° F. which will maintain the freshness of the produce and slow further respiration and decay.
The present invention utilizes a suitable corrugated paperboard container design sized for the particular produce but one without having a wax or other chemical compound impregnated into the material which causes problems with subsequent repulping-recycling. Given the requirements of shipping fresh produce with the boxes being stacked one atop another, each of the individual containers 10 must have sufficient top-to-bottom stacking strength so they maintain their structural properties when stacked into a palletized form.
Turning now to the construction of container 10, it will be seen that it is comprised of bottom wall 12, two opposed side walls 14, 16 and two opposed end walls 18, 20. It will be fabricated from a single piece of cut and scored corrugated paperboard. A pair of opposed strap members 22, 24 extend along each side and top of container 10. A portion of each strap 22, 24 is folded over one of the top end edges and overlies a portion of its respective end wall. A central opening extends between the inner edges of straps 22, 24 and forms the opening through which the fresh-picked produce is packed and through which it may be extracted after shipment. Again, typical of this known container structure is a pair of stacking tabs 26, 28 extending upwardly from each end wall 18, 20. Similarly, along each side wall 14, 16 and extending upwardly therefrom are individual stacking tabs each indicated at 30. These stacking tabs 30 will fit within receiving slots each indicated at 32 located along the bottom edge of side walls 14, 16. Again, these are well known features utilized for stacking purposes. Hand hold apertures 34 are located in each end wall 18, 20 to allow easy pickup and handling. If necessary for vertical stacking strength and as illustrated in FIG. 1, an inclined corner panel indicated at 36 can be provided in each corner of container 10. Corner panels are well known for use in containers to provide additional stacking strength. Perforations or apertures 38 are provided within container 10 for air and gas flow during both the cooling process and throughout shipment to the destination. This particular container is of a construction whereby the folding and erection can take place in the field utilizing a series of interlocking tabs and slots (not shown). An alternative would be to machine form a substantially similar container by gluing it together and then utilizing the formed container in the present invention.
Turning now to a description of plastic bag indicated at 40 it may be seen that bag 40 has a length and width which is approximately equal to the length and width of container 10. Bag 40 is constructed of tough, flexible, water impervious plastic and could be on the order of one mil or more in thickness. While the length and width of bag 40 is approximately the length and width of container 10, its overall height will be approximately that of depth plus two widths of container 10. In the field when fresh-cut produce is ready to be packed, individual plastic bags 40 will be inserted downwardly into containers 10 where the bottom of bag 40 will then be spread out to conform to the bottom rectangular configuration of bottom wall 12. As bag 40 is manipulated into place, its side walls will move downwardly into the opening on the top but a substantial portion towards the top of bag 40 will remain exposed and above the horizontal plane of straps 22, 24. Alignment means, such as sunburst holes, can be provided in the bottom of container 10 for quickly placing bag 40 in place. What is thusly formed when the plastic bag is in its location within container 10 is a substantially water-impervious receiving bag for accepting fresh-cut produce. It is desirable that there be no perforations within the lower half of plastic bag 40 so that any free water within the produce or the free water which is added as part of the invention will be securely retained by the plastic bag.
Turning now to FIG. 2, the series of process steps forming the present invention will be described. At the beginning a plastic bag 40 is inserted into the typical shipping container 10. Again, to reiterate, the shipping container 10 is one that does not utilize any objectionable chemical additive within the corrugated paperboard which would prohibit or otherwise make repulping and recycling difficult. For purposes of illustrating a substantially continuous in-line process, a conveyor means is shown at 42 and it has an infeed end 44 and outfeed end 46. Taking place in close proximity to produce being loaded into the bottom of a container with the bag inserted therein will be the harvest and cleaning step. Of course, it is highly desirable to pack the fresh-cut produce as soon after it is harvested as is practical. As the produce is being harvested the ambient temperature is relatively high, ranging anywhere from between 60° F. to 90° F., sometimes lower and sometimes higher. With this ambient temperature, the produce temperature is relatively high and if stored would soon spoil.
When packing typical harvested row crops such as broccoli, celery, mixed green and the like, a suitably sized container and its related bag will be receiving individual pieces of produce that are inserted into the opening of the container. This is usually done by hand, although it could be done mechanically. Depending upon the weight of produce to be packed, the container is filled while the outwardly extending walls of the plastic bag remain in an open configuration. At the next step in the process, a predetermined amount of water is added to the packed produce. It is added in a suitable form such as in droplet form by being sprayed over the top surface of the produce resting in the container. The amount of water added is determined based on the weight of the packed produce and the temperature of the produce. Typically the shipping and storage temperature is to be between 32° and 34° F. When utilizing a vacuum cooling step, it is known that in order to reduce dehydration of the produce, i.e., drawing free water out of the produce, an amount of water should be added which should be approximately 1% by weight of the fresh produce for every 10° F. of needed cooling. For example, if the pulp temperature of the fresh-cut produce is 85° F. and the desired cooled temperature is 35° F., approximately 5% by weight of the packed produce should be added as free water. Care should be taken when the free water is added to avoid spraying or otherwise allowing the free water to contact the underlying container 10 keeping in mind that container 10 is regular corrugated paperboard. The objective is to spray or otherwise uniformly cover the packed produce with the predetermined amount of free water prior to it being vacuum cooled.
After the required amount of free water has been added, any excess flowing to the bottom of the plastic bag but being retained within the bag, the top neck of the bag is neatly folded over the surface of the product and tucked in beneath the edges of straps 22, 24. The top of the bag will remain loosely closed in that there is not an effective seal created tightly closing off the produce to the atmosphere.
After the bag is closed, a final check and off load of the packed produce can be made at outfeed end 46. Thereafter, a predetermined number of packed containers will be palletized in the typical manner. For example, containers filled with celery could be palletized in tiers of five, seven or eight high, while containers with broccoli could be palletized in tiers of four-2×2-ten to twelve high. These palletizing configurations are all well known to those skilled in the art.
With the fresh produce so packed and palletized, the pallets are then moved to a vacuum cooler where depending upon its capacity, the appropriate number of pallets will be inserted therein. The vacuum cooling step is, as previously mentioned, known for cooling produce. However, in the present invention as the vacuum cooling sequence is started and the pressure reduced, the free water will begin to evaporate drawing the heat out of the fresh-cut produce, thereby bringing its temperature down relatively rapidly. The water vapor is typically condensed on coils which are maintained at a temperature to yield a cooled product within the range of 32°-34° F. It has been found that when cooling relatively dense produce like celery or broccoli it takes approximately one hour to bring the temperature of the produce down to its desired range of from 32°-34° F. During this time period, approximately the amount of free water added will be evaporated allowing the produce to cool with minimum dehydration. At the end of the cooling step the vacuum should be released slowly, allowing the pressure to come back up to atmospheric over approximately a 5-10 minute period so as to not damage the produce by driving any free water back into the produce. Similarly, it has been found in leafy produce such as romaine and mixed leaf that the vacuum cooling step only takes from between 20 to 30 minutes depending upon the particular type of produce and likewise that the vacuum should be release slowly.
During storage and shipment which will be within refrigerated units, the water content of the packed produce will remain relatively stable. At the receiving end, the produce will be unpacked where it has been found to be very fresh appearing and wholesome, even after being refrigerated for long periods. Further, it has been found that after unpacking, the produce does not have to be rejuvenated by adding additional water or ice prior to marketing.
Other process variations are available, for example, when shipping to a destination where fumigation is required. If cool, fresh produce is to be shipped to Japan, for example, there may be a fumigation requirement. In this case a relatively shorter bag length is utilized leaving an open strip along the top of the produce whereby a fumigating gas will be allowed to diffuse over the fresh produce. A separate strip of plastic is applied over the open area of the bag during shipment and removed prior to fumigation.
Another option would be to provide an easily tearable perforated line around the entire circumference of the plastic bag but at a location at the top edge of the container (so as to leave bottom portion of the bag as moisture impervious) so that after receiving the produce in Japan, the top of the bag can be readily torn away exposing the produce for fumigation.
Still another option involves the use of evaporative liquids other than regular water. Liquids including additives or multifuntional liquids can be utilized to provide enhanced product performance. For example, additives such as lemon juice could be utilized to minimize browning and odor control additives may be utilized.
While a detailed description has been provided of the preferred embodiment and several alternatives, it may occur to those skilled in the art to make modifications and changes to the process which will nevertheless still come within the scope and spirit of the present invention. All such changes and modifications are intended to be included within the scope of the appended claims. | A process for packing, cooling and shipping fresh produce incorporates a standard corrugated paperboard, stackable container without utilizing any water resistant chemical compounds, together with a moisture-impervious plastic bag which is inserted into the paperboard container. The free ends of the plastic bag extend upwardly and above the top plane of the paperboard container as produce is packed and thereafter allows an opening for a preselected amount of free water to be applied over the fresh-packed produce. Thereafter, the top of the bag is tucked in providing a loose closure and the package is palletized and inserted into a vacuum chamber where the temperature of the produce is rapidly brought down to its storage and shipping temperature. | 1 |
REFERENCE TO RELATED APPLICATIONS
[0001] Reference is made to PCT Patent Application PCT/IL2004/000430, filed May 20, 2004, entitled “ENDOSCOPIC BITE BLOCK”, the disclosure of which is hereby incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to the field of bite blocks for endoscopic use and specifically to endoscopic bite blocks suitable for use with gas sampling or delivery cannulae.
BACKGROUND OF THE INVENTION
[0003] The following U.S. Patents are believed to represent the current state of the art: U.S. Pat. Nos. 5,174,284; 6,257,238; 6,422,240; 5,273,032 and 5,513,634.
SUMMARY OF THE INVENTION
[0004] The present invention seeks to provide a new endoscopic bite block.
[0005] There is thus provided in accordance with a preferred embodiment of the present invention a bite block assembly adapted for capnography and oxygen delivery to a subject, the bite block assembly including a first capnography passageway adapted for passage therethrough of exhaled breath from the subject to a capnograph, and a second oxygen delivery passageway, separate from the first passageway, adapted for passage therethrough of oxygen from an oxygen source to the mouth of the subject.
[0006] Preferably the bite block assembly also includes a gas collection cannula having formed therein the first capnography passageway. Additionally the gas collection cannula also includes an oxygen delivery cannula adapted to deliver oxygen from the oxygen source to the nostrils of the subject. More preferably the oxygen delivery cannula is connected to the oxygen source by a gas delivery tube.
[0007] Preferably the bite block assembly also includes a bite block having formed therein the second oxygen delivery passageway.
[0008] More preferably the bite block assembly also includes a tube element adapted to connect the oxygen delivery cannula to the second oxygen delivery passageway. Additionally, the tube element includes a branch of the gas delivery tube, and is adapted to connect to the second oxygen delivery passageway. Additionally the tube element is sealed by a normally closed valve. Preferably the normally closed valve includes a luer valve. Additionally a mating luer portion of the luer valve is mounted onto the oxygen delivery passageway.
[0009] Preferably the tube element is permanently mounted onto the bite block and is adapted to connect to the gas delivery tube at a connection point formed therein. Additionally the connection point is sealed by a normally closed valve. Preferably the normally closed valve includes a luer valve. More preferably a mating luer portion of the luer valve is mounted onto the tube element.
[0010] There is thus provided in accordance with another preferred embodiment of the present invention, a capnography system including a capnograph, a bite block adapted to maintain the mouth of a subject open during a medical procedure, an exhaled breath sampling element which is connectable to the capnograph and mountable onto the bite block, and an oral oxygen delivery passageway which is connectable to the bite block for delivering oxygen from an oxygen source to the mouth of the subject.
[0011] Preferably the exhaled breath-sampling element has at least one gas collection passageway, formed therein, the gas collection passageway being configured to collect exhaled breath of the subject. Additionally the at least one gas collection passageway includes a nasal gas collection passageway configured for collecting breath exhaled through at least one nostril of the subject. Additionally or alternatively the at least one gas collection passageway includes an oral gas collection passageway configured for collecting breath exhaled through the mouth of the subject.
[0012] Preferably the capnography system also includes a nasal gas delivery passageway for delivering oxygen from the oxygen source to at least one nostril of the subject. Additionally the nasal gas delivery passageway is connected to the oxygen source by a gas delivery tube. More preferably the oral oxygen delivery passageway includes a tubular branch of the gas delivery tube.
[0013] Preferably the oral oxygen delivery passageway is sealed by a normally closed valve. Additionally the normally closed valve includes a luer valve. More preferably a mating luer portion of the luer valve is mounted onto the oral oxygen delivery passageway.
[0014] Preferably the oral oxygen delivery passageway is permanently mounted onto the bite block and is adapted to connect to the gas delivery tube at a connection point formed therein. Additionally the connection point is sealed by a normally closed valve. More preferably the normally closed valve includes a luer valve. Additionally a mating luer portion of the luer valve is mounted onto the oral oxygen delivery passageway.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
[0016] FIGS. 1A and 1B are simplified pictorial illustrations of an oral nasal sampling cannula forming part of an endoscopic bite block assembly, constructed and operative in accordance with a preferred embodiment of the present invention, in retracted and extended orientations respectively;
[0017] FIGS. 2A and 2B are front-view and rear-view simplified pictorial illustrations of an endoscopic bite block forming part of an endoscopic bite block assembly, constructed and operative in accordance with a preferred embodiment of the present invention;
[0018] FIG. 3 is a simplified sectional pictorial illustration of the endoscopic bite lock of FIGS. 2A and 2B , taken along sections lines III-III in FIG. 2B ;
[0019] FIG. 4 is a simplified schematic illustration of the connection between the oral nasal cannula of FIGS. 1A and 1B and the endoscopic bite block of FIGS. 2A-3 ;
[0020] FIGS. 5A , 5 B, 5 C, 5 D, 5 E, 5 F and 5 G are pictorial illustrations of various stages of typical use of the endoscopic bite block assembly of FIGS. 1A-4 ;
[0021] FIGS. 6A and 6B are simplified pictorial illustrations of an oral nasal cannula forming part of an endoscopic bite block assembly, constructed and operative in accordance with another preferred embodiment of the present invention, in retracted and extended orientations respectively;
[0022] FIGS. 7A and 7B are front-view and rear-view simplified pictorial illustrations of an endoscopic bite block forming part of an endoscopic bite block assembly, constructed and operative in accordance with another preferred embodiment of the present invention;
[0023] FIG. 8 is a simplified sectional pictorial illustration of the endoscopic bite block of FIGS. 7A and 7B , taken along sections lines VIII-VIII in FIG. 7B ;
[0024] FIG. 9 is a simplified schematic illustration of the connection between the oral nasal cannula of FIGS. 6A and 6B and the endoscopic bite block of FIGS. 7A-8 ;
[0025] FIGS. 10A , 10 B, 10 C, 10 D, 10 E, 10 F and 10 G are pictorial illustrations of various stages of typical use of the endoscopic bite block assembly of FIGS. 5A-9 ;
[0026] FIGS. 11A and 11B are simplified pictorial illustrations of an oral nasal cannula forming part of an endoscopic bite block assembly, constructed and operative in accordance with yet another preferred embodiment of the present invention, in retracted and extended orientations respectively;
[0027] FIGS. 12A and 12B are front-view and rear-view simplified pictorial illustrations of an endoscopic bite block forming part of an endoscopic bite block assembly, constructed and operative in accordance with yet another preferred embodiment of the present invention;
[0028] FIG. 13 is a simplified sectional pictorial illustration of the endoscopic bite block of FIGS. 12A and 12B , taken along sections lines XIII-XIII in FIG. 12B ;
[0029] FIG. 14 is a simplified schematic illustration of the connection between the oral nasal cannula of FIGS. 11A and 11B and the endoscopic bite block of FIGS. 12A-13 ; and
[0030] FIGS. 15A , 15 B, 15 C, 15 D, 15 E, 15 F and 15 G are pictorial illustrations of various stages of typical use of the endoscopic bite block assembly of FIGS. 11A-14 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0031] A bite block is a device commonly used during upper gastro-intestinal endoscopic procedures to facilitate passage of an esophago-gastro-duodenoscopy (EGD) endoscope. The purpose of the bite block is to allow the physician to perform the procedure without the subject interfering by biting and damaging the endoscope tubing inserted via his mouth, whether voluntarily or involuntarily.
[0032] The upper gastro-intestinal endoscopic procedure itself, together with the use of a bite block, is often highly uncomfortable for the subject and therefore it is very common for the subject to be sedated during the procedure. Despite this, it is common for the subject to show opposition to the procedure.
[0033] During upper gastro-intestinal endoscopy, and especially during long duration procedures performed under sedation, CO2 monitoring is often performed using a separate nasal or oral/nasal cannula in conjunction with a bite block. Concomitant use of bite blocks and cannulae may noticeably affect capnographic performance for a number of reasons, including inter alia misalignment between the cannula and the bite block and inefficient oral sampling due to the space taken up by the endoscope. The present invention provides a solution that generally does not affect the capnographic performance.
[0034] Reference is now made to FIGS. 1A and 1B , which are simplified pictorial illustrations of an oral nasal sampling cannula forming part of an endoscopic bite block assembly, constructed and operative in accordance with a preferred embodiment of the present invention, in retracted and extended orientations respectively.
[0035] FIGS. 1A and 1B show an oral nasal sampling cannula 10 , which is adapted for collection of gases, such as carbon dioxide, exhaled by a subject, and for supplying oxygen to the subject.
[0036] The oral nasal sampling cannula 10 comprises a main body portion 12 , having formed therein an exhaled breath collection bore 14 and an oxygen delivery bore 16 . A pair of hollow nasal prongs 18 , which are adapted for insertion into the nostrils of the subject, is integrally formed with the main body portion 12 . A hollow oral prong 22 , which is formed with a limiting rib 23 and a cut-away tip 24 , is mounted onto a bottom surface of main body portion 12 . An oral breath directing element 26 , which is preferably in the shape of a cut-away tube, is slidably mounted onto oral prong 22 by a mounting portion 28 , and positioning of the oral breath directing element 26 is limited by the limiting rib 23 of oral prong 22 .
[0037] A channel farmed in oral prong 22 is in fluid flow connection with channels formed in nasal prongs 18 , thereby fanning, a single junction 32 . Single junction 32 is in fluid flow communication with exhaled breath collection bore 14 , which in turn is in fluid flow communication with an exhaled breath collection tube 34 , which is adapted to be connected to a breath test analyzer or a capnograph (not shown), such as Microcap® which is commercially available from Oridion Medical LTD. of Jerusalem, Israel.
[0038] Main body portion 12 is formed with oxygen delivery openings 36 , which are in fluid flow communication with oxygen delivery bore 16 , which in turn is in fluid flow communication with an oxygen delivery tube 38 . Alternatively, at least one nasal oxygen delivery prong, adapted for insertion into the subject's nostril, may be used instead of oxygen delivery openings 36 . Oxygen delivery tube 38 is adapted to be connected to a source of oxygen (not shown).
[0039] Oxygen delivery tube 38 and exhaled breath collection tube 34 may optionally be placed around the ears of the subject, thereby stabilizing the oral nasal sampling cannula 10 on the subject's face, such that any movement of the subject will have a negligible effect on the placement of the oral nasal sampling cannula 10 .
[0040] It is appreciated that oral breath directing element 26 may be in a retracted orientation as shown in FIG. 1A , or in an extended orientation as shown in FIG. 1B , thereby allowing the oral nasal sampling cannula 10 to be suited to the facial dimensions of the subject, resulting in more efficient collection of exhaled breath.
[0041] Reference is now made to FIGS. 2A and 2B , which are front-view and rear-view simplified pictorial illustrations of an endoscopic bite block forming part of an endoscopic bite block assembly constructed and operative in accordance with a preferred embodiment of the present invention and to FIG. 3 , which is a simplified sectional pictorial illustration thereof.
[0042] FIGS. 2A , 2 B and 3 show an endoscopic bite block 50 , which is adapted to be inserted into the mouth of a subject while the subject is sedated, to ensure that the mouth of the subject is maintained open during the endoscopy process and that the subject does not interfere with the process by biting on the medical instruments used.
[0043] The endoscopic bite block 50 includes a main body portion 52 , having formed rein a central opening 54 . A hollow tubular portion 56 extends distally from main body portion 52 , such that the opening of tubular portion 56 is an extension of central opening 54 . Central opening 54 is of a first height, indicated by H 1 in FIG. 3 , which is typically 16 to 20 mm in bite blocks for adult use, which is the height required by medical personnel for performing an endoscopy. In order to ensure that during breath sampling, oral prong 22 of oral nasal sampling cannula 10 ( FIGS. 1A and 1B ) does not interfere with the space required by medical personnel for performing the endoscopy procedure, the height of tubular portion 56 is greater than the height H 1 of the central opening 54 as indicated by 112 in FIG. 3 , and is typically 2 to 4 mm more than height H 1 (18 to 24 mm).
[0044] An outer surface 58 of tubular portion 56 is formed with top and bottom teeth engagement surfaces 60 and 62 , such that top teeth engagement surface 60 is relatively forward of bottom teeth engagement surface 62 . This structure facilitates easy and accurate biting of the bite block 50 by a subject, as it is suited to the jaw morphology of a closed human mouth. Surface 58 is additionally formed with jaw engagement recesses 64 , which are formed forwardly of teeth engagement surfaces 60 and 62 , respectively.
[0045] A top inner surface 70 of main body portion 52 is formed with a longitudinal groove 72 having a transverse surface 73 , which is adapted to accommodate oral prong 22 and oral breath directing element 26 of the oral nasal sampling cannula 10 ( FIGS. 1A and 1B ), as described with more detail herein below with reference to FIG. 4 .
[0046] A flexible barrier 76 , preferably comprised of several flaps 78 , is disposed within central opening 54 , thereby substantially closing off the central opening and preventing dilution of exhaled breath by ambient air during sampling. An opening 80 is preferably maintained within flexible barrier 76 , thereby ensuring a small part of central opening 54 remains open in order to enable the subject to inhale external air. The flexible barrier 76 ensures that a majority of the subject's orally exhaled breath will be directed toward oral prong 22 ( FIGS. 1A and 1B ) thereby ensuring accurate sampling of the subject's breath. Opening 80 is preferably placed at a top part of central opening 54 near the cut-away tip 24 of oral prong 22 ( FIGS. 1A and 1B ), thereby directing exhaled breath toward the oral prong 22 as it is the only substantial exit.
[0047] The flaps 78 are preferably formed of a plastic material selected to be of suitable thickness to maintain their position when undisturbed, yet bend readily when pushed by an endoscope probe, and thus do not limit the actions of the medical personnel performing the endoscopy. However, the flaps 78 preferably close back around the endoscope probe, thus maintaining a substantially closed oral cavity volume and allowing most of the exchange of gases to occur close to the opening 80 of the flexible barrier 76 which is close to the cut-away tip 24 of oral prong 22 ( FIGS. 1A and 1B ) from which capnographic sampling can be performed accurately. Additionally, the flaps 78 are preferably transparent, thus enabling medical personnel to see into the oral cavity during the endoscopy procedure.
[0048] Two attachment surfaces 82 , each formed with a slit 84 , extend horizontally outwardly from main body portion 52 . Slits 84 are adapted to connect to a band which is placed around the subject's head and is used to maintain the endoscopic bite block 50 firmly in position during the endoscopy procedure. Preferably, slits 84 are located above a horizontal centerline of main body portion 52 , such that the connected band will tend to exert a stronger pull to the top of the main body portion 52 , thus assisting in overcoming the subject's tendency to tilt the bite block 50 outward during the endoscopy procedure and in maintaining the bite block 50 upright in the subject's mouth.
[0049] Reference is now made to FIG. 4 , which is a simplified schematic illustration of the connection between the oral nasal sampling cannula of FIGS. 1A and 1B and the endoscopic bite block of FIGS. 2A-3 .
[0050] As seen in FIG. 4 , oral prong 22 of oral nasal sampling cannula 10 is accommodated within groove 72 of bite block 50 , such that a bottom surface of oral breath directing element 26 engages transverse surface 73 of the groove 72 . It is appreciated that transverse surface 73 is located below an inner surface of tubular portion 56 in order to ensure that air exhaled by the subject into tubular portion 56 will be directed toward groove 72 and oral prong 22 .
[0051] Reference is now made to FIGS. 5A , 5 B, 5 C, 5 D, 5 E, 5 F and 5 G, which are pictorial illustrations of various stages of typical use of the endoscopic bite block assembly of FIGS. 1A-4 .
[0052] As seen in FIG. 5A , the nasal prongs 18 of the oral nasal sampling cannula 10 are placed in the subjects nostrils, preferably before the subject is sedated. Preferably, the exhaled breath collection tube 34 and the oxygen delivery tube 38 are placed around the subject's ears, in order to ensure the stability of the oral nasal sampling cannula 10 on the subject's face. As seen in the enlarged portion of FIG. 5A , at this stage the oral breath-directing element 26 is in its retracted orientation, indicated by the length H 3 .
[0053] Turning to FIG. 5B , it is seen that the oral breath directing element 26 is extended to accommodate the facial dimensions of the subject, revealing part of oral prong 22 . Preferably, the oral breath-directing element is moved down to a point in which a bottom end thereof is at the height of the top of the bottom lip of the subject, its new length being indicated by H 4 . This action is preferably preformed by medical personnel, but may alternatively be performed by the subject himself, a family member, or any other person.
[0054] FIG. 5C illustrates the insertion of bite block 50 into the mouth of the subject, such that main body portion 52 engages the outer surface of the subject's lips and the tubular portion 56 is inside the subject's mouth. A strap, indicated by reference numeral 90 , is attached to slits 84 of attachment surfaces 82 and is placed around the subject's head, thereby securing the bite block 50 in place. This stage is preferably performed when the subject is sedated, but may alternatively he performed prior thereto.
[0055] As seen in the enlarged portion of FIG. 5C , the oral breath directing element 26 and the oral prong 22 are accommodated in groove 72 , such that a bottom surface of the oral breath directing element 26 engages transverse surface 73 of groove 72 . Additionally, if oral breath directing element 26 has been extended more than necessary for the facial features of the subject, the transverse surface 73 pushes the oral breath-directing element 26 back, until it is optimally positioned. The lips of the subject, indicated by reference numeral 92 preferably engage jaw engagement recesses 64 , and the top and bottom teeth of the subject, indicated by reference numerals 94 and 96 engage top and bottom teeth engagement surfaces 60 and 62 , respectively.
[0056] Turning to FIG. 5D , it is seen that air exhaled orally by the subject, indicated by arrows, passes through the bore of tubular portion 56 , and is directed toward oral breath directing element 26 and oral prong 22 by the flaps 78 of flexible barrier 76 . Air that is exhaled nasally by the subject passes through nasal prongs 18 .
[0057] FIG. 5E illustrates the sedated subject, having the nasal prongs 18 of the oral nasal sampling cannula 10 in his nostrils and the endoscopic bite block 50 placed in his mouth and strapped to his head. Preferably, once the subject is sedated, oxygen is supplied to the nose of the subject via oxygen delivery openings 36 of oral nasal sampling cannula 10 , as indicated by arrows in the enlarged portion of FIG. 5E . The oxygen is supplied to oxygen delivery openings 36 via oxygen delivery bore 16 ( FIGS. 1A and 1B ) and oxygen delivery tube 38 .
[0058] Turning to FIG. 5F , it is seen that when the subject is sedated, he tends to move or slump his head, thereby moving oral nasal sampling cannula 10 relative to bite block 50 , as indicated by angle a in the enlarged portion of FIG. 5F . The feature of the present invention which provides oral nasal sampling cannula 10 which is physically separated from bite block 50 and the placement of oral breath directing element 26 and oral prong 22 within groove 72 , ensure that even when the subject moves or slumps his bead, the oral prong 22 and nasal prongs 18 will be maintained in their respective places, and accurate sampling will continue. Additionally, the placement of oral prong 22 within groove 72 provides a counter force to force applied by the subject's tongue to push at least the top portion of the bite block 50 out of the subject's mouth, thus ensuring accurate placement of the bite block.
[0059] As seen in FIG. 5G , an endoscope probe 98 is inserted into the bore of tubular portion 56 of bite block 50 , for performing an endoscopy procedure. During the insertion of endoscope probe 98 and its presence in the subject's mouth and pharynx, flaps 78 of flexible barrier 76 bend slightly inward to allow the passage of the endoscope probe 98 , as seen with particular clarity in the enlarged portion of FIG. 5G . However, the central opening 54 of bite block 50 remains substantially closed by flaps 78 , thereby separating the exhaled breath of the subject which is in the bore of tubular portion 56 from the ambient air.
[0060] Additionally, the sampling may continue during the presence of the endoscope probe 98 in the pharynx of the subject, as the tubular portion 56 is of a slightly larger diameter than the central opening 54 , thereby ensuring that medical personnel have the space required for the endoscopy procedure and sampling can take place from the space defined by the difference between heights H 2 and H 1 ( FIG. 3 ), as indicated by arrows in the enlarged portion of FIG. 5G .
[0061] It is appreciated that following the endoscopy, the bite block 50 may be removed from the subject's mouth, preferably by medical personnel. However, the sampling of exhaled breath through nasal prongs 18 which remain in the subject's nostrils and through oral prong 22 which remains near the subject's mouth, preferably continues until the subject has awaken from the sedation. This is necessary because the subject's breath must be monitored as long as the subject is sedated.
[0062] Reference is now made to FIGS. 6A and 6B , which are simplified pictorial illustrations of an oral nasal sampling cannula forming part of an endoscopic bite block assembly, constructed and operative in accordance with another preferred embodiment of the present invention, in retracted and extended orientations respectively.
[0063] FIGS. 6A and 6B show an oral nasal sampling cannula 110 , which is adapted for collection of gases, such as carbon dioxide, exhaled by a subject, and for supplying oxygen to the subject.
[0064] The oral nasal sampling cannula 110 comprises a main body portion 112 , having formed therein an exhaled breath collection bore 114 and an oxygen delivery bore 116 . A pair of hollow nasal prongs 118 , which are adapted for insertion into the nostrils of the subject, is integrally formed with the main body portion 112 . A hollow oral prong 122 , which is formed with a limiting rib 123 and a cut-away tip 124 , is mounted onto a bottom surface of main body portion 112 . An oral breath directing element 126 , which is preferably in the shape of a cut-away tube, is slidably mounted onto oral prong 122 by a mounting portion 128 , and positioning of the oral breath directing element 126 is limited by the limiting rib 123 of oral prong 122 .
[0065] A channel formed in oral prong 122 is in fluid flow connection with channels formed in nasal prongs 118 , thereby forming a single junction 132 . Single junction 132 is in fluid flow communication with exhaled breath collection bore 114 , which in turn is in fluid flow communication with an exhaled breath collection tube 134 , which is adapted to be connected to a breath test analyzer or a capnograph (not shown), such as Microcap® which is commercially available from Oridion Medical LTD. of Jerusalem, Israel.
[0066] Main body portion 112 is formed with oxygen delivery openings 136 , which are in fluid flow communication with oxygen delivery bore 116 , which in turn is in fluid flow communication with an oxygen delivery tube 138 . Alternatively, at least one nasal oxygen delivery prong, which is adapted to be inserted into the nostril of the subject, may be used instead of oxygen delivery openings 136 . Oxygen delivery tube 138 is preferably formed with a T-element 140 , connecting the oxygen delivery tube 138 to an oral oxygen delivery tube 142 . Oxygen delivery tube 138 is adapted to be connected to a source of oxygen (not shown). Oral oxygen delivery tube 142 is preferably normally dosed by a valve element 144 . Typically, the valve is a luer type valve.
[0067] Oxygen delivery tube 138 and exhaled breath collection tube 134 may optionally be placed around the ears of the subject, thereby stabilizing the oral nasal sampling cannula 110 on the subject's face, such that any movement of the subject will have negligible effect on the placement of the oral nasal sampling cannula 110 .
[0068] It is appreciated that oral breath directing element 126 may be in a retracted orientation as shown in FIG. 6A , or in an extended orientation as shown in FIG. 6B , thereby allowing the oral nasal sampling cannula 110 to be suited to the facial dimensions of the subject, resulting in more efficient collection of exhaled breath.
[0069] Reference is now made to FIGS. 7A and 7B , which are front-view and rear view simplified pictorial illustrations of an endoscopic bite block forming part of an endoscopic bite block assembly constructed and operative in accordance with a preferred embodiment of the present invention and to FIG. 8 , which is a simplified sectional pictorial illustration thereof.
[0070] FIGS. 7A , 7 B and 8 show an endoscopic bite block 150 , which is adapted to be inserted into the mouth of a subject while the subject is sedated, to ensure that the mouth of the subject is maintained open during the endoscopy process and that the subject does not interfere with the process by biting on the medical instruments used.
[0071] The endoscopic bite block 150 includes a main body portion 152 , having formed therein a central opening 154 . A hollow tubular portion 156 extends distally from main body portion 152 , such that the opening of tubular portion 156 is an extension of central opening 154 . Central opening 154 is of a first height, indicated by H 1 in FIG. 8 , which is typically 16 to 20 mm in bite blocks for adult use, which is the height required by medical personnel for performing an endoscopy. In order to ensure that during breath sampling, oral prong 122 of oral nasal sampling cannula 110 ( FIGS. 6A and 6B ) does not interfere with the space required by medical personnel for performing the endoscopy procedure, the height of tubular portion 156 is greater than the height H 1 of central opening 154 as indicated by H 2 in FIG. 8 , and is typically 2 to 4 mm more than height H 1 (18 to 24 mm).
[0072] An outer surface. 158 of tubular portion 156 is formed with top and bottom teeth engagement surfaces 160 and 162 , such that top teeth engagement surface 160 is relatively forward of bottom teeth engagement surface 162 . This structure facilitates easy and accurate biting of the bite block 150 by a subject, as it is suited to the jaw morphology of a closed human mouth. Surface 158 is additionally formed with jaw engagement recesses 164 , which are formed forwardly of teeth engagement surfaces 160 and 162 , respectively.
[0073] A top inner surface 170 of main body portion 152 is formed with a longitudinal groove. 172 having a transverse surface 173 , which is adapted to accommodate oral prong 122 and oral breath directing element 126 of the oral nasal sampling cannula 110 ( FIGS. 6A and 6B ), as described with more detail hereinbelow with reference to FIG. 9 .
[0074] A tubular portion 174 is formed on a side of outer surface 158 of tubular portion 156 . Tubular portion 174 is adapted to threadably engage oral oxygen delivery tube 142 ( FIGS. 6A and 6B ), thereby opening valve 144 to the passage of gases and thus supplying oxygen directly to the oral cavity of the subject. Preferably, tubular portion 174 includes a luer portion corresponding to luer valve element 144 . It is appreciated that tubular portion 174 is formed on outer surface 158 of tubular portion 156 , in order to ensure that the oral oxygen delivery does not interfere with the procedure performed by the medical personnel and so that the oxygen flow does not directly interfere with the CO2 sampling.
[0075] A flexible barrier 176 , preferably comprised of several flaps 178 , is disposed within central opening 154 , thereby substantially closing off the central opening and preventing dilution of exhaled breath by ambient air during sampling. An opening 180 is preferably maintained within flexible barrier 176 , thereby ensuring a small part of central opening 154 to remain open in order to enable the subject to inhale external air. The flexible barrier 176 ensures that a majority of the subject's orally exhaled breath will be directed toward oral prong 122 ( FIGS. 6A and 6B ) thereby ensuring accurate sampling of the subject's breath. Opening 180 is preferably placed at a top part of central opening 154 near the cut-away tip 124 of oral prong 122 ( FIGS. 6A and 6B ), thereby directing exhaled breath toward the oral prong 122 as it is the only substantial exit.
[0076] The flaps 178 are preferably formed of a plastic material selected to be of suitable thickness to maintain their position when undisturbed, yet bend readily when pushed by an endoscope probe, and thus do not limit the actions of the medical personnel performing the endoscopy. However, the flaps 178 preferably close back around the endoscope probe, thus maintaining a substantially closed oral cavity volume, and allowing most of the exchange of gases to occur close to the opening 180 of the flexible barrier 176 , which opening is close to the cut-away tip 124 of oral prong 122 from which capnographic sampling can be performed accurately. Additionally, the flaps 178 are preferably transparent, thus enabling medical personnel to see into the oral cavity during the endoscopy procedure.
[0077] Two attachment surfaces 182 , each formed with a slit 184 , extend horizontally outwardly from main body portion 152 . Slits 184 are adapted to connect to a band which is place around the subject's head and is used to maintain the endoscopic bite block 150 firmly in position during the endoscopy procedure. Preferably, slits 184 are located above a horizontal centerline of main body portion 152 , such that the connected band will tend to exert a stronger pull to the top of the main body portion 152 , thus assisting in overcoming the subject's tendency to tilt the bite block 150 outward during the endoscopy procedure and in maintaining the bite block 150 upright in the subject's mouth.
[0078] Reference is now made to FIG. 9 , which is a simplified schematic illustration of the connection between the oral nasal sampling cannula of FIGS. 6A and 6B and the endoscopic bite block of FIGS. 7A-8 .
[0079] As seen in FIG. 9 , oral prong 122 of oral nasal sampling cannula 110 is accommodated within groove 172 of bite block 150 , such that a bottom surface of oral breath directing element 126 engages transverse surface 173 of the groove 172 . It is appreciated that transverse surface 173 is located below an inner surface of tubular portion 156 in order to ensure that air exhaled by the subject into tubular portion 156 will be directed toward groove 172 and oral prong 122 .
[0080] Additionally, valve 144 ( FIGS. 6A and 6B ) of oral oxygen delivery tube 142 is accommodated in tubular portion 174 of endoscopic bite block 150 , thereby opening the valve element and forming a fluid flow engagement between oxygen delivery tube 138 and tubular portion 174 of endoscopic bite block 150 , which is in fluid flow engagement with the oral cavity of the subject.
[0081] Reference is now made to FIGS. 10A , 10 B, 10 C, 10 D, 10 E, 10 F and 10 G, which are pictorial illustrations of various stages of typical use of the endoscopic bite block assembly of FIGS. 6A-9 .
[0082] As seen in FIG. 10A , the nasal prongs 118 of the oral nasal sampling cannula 110 are placed in the subjects nostrils, preferably before the subject is sedated. Preferably, the exhaled breath collection tube 134 and the oxygen delivery tube 138 are placed around the subject's ears, in order to ensure the stability of the oral nasal sampling cannula 110 on the subject's face. As seen in the enlarged portion of FIG. 10 A, at this stage the oral breath-directing element 126 is in its retracted orientation, indicated by the length 113 . At this stage, oral oxygen delivery tube 142 is not connected to the bite block 150 ( FIGS. 7A-8 ).
[0083] Turning to FIG. 10B , it is seen that the oral breath directing element 126 is extended to accommodate the facial dimensions of the subject, revealing part of oral prong 122 . Preferably, the oral breath-directing element is moved down to a point in which a bottom end thereof is at the height of the top of the bottom lip of the subject, its new length being indicated by H 4 . This action is preferably preformed by medical personnel, but may alternatively be performed by the subject himself, a family member, or any other person.
[0084] FIG. 10C illustrates the insertion of bite block 150 into the mouth of the subject, such that main body portion 152 engages the outer surface of the subject's lips and the tubular portion 156 ( FIGS. 7A-8 ) is inside the subject's mouth. Additionally, valve 144 of oral oxygen delivery tube 142 is inserted, preferably by medical personnel, into tubular portion 174 of endoscopic bite block 150 , as indicated by an arrow in the enlarged portion of FIG. 10C , thereby opening the valve and allowing passage of fluids from the oral oxygen delivery tube 142 into the oral cavity of the subject.
[0085] A strap, indicated by reference numeral 190 , is attached to slits 184 of attachment surfaces 182 and is placed around the subject's head, thereby securing the bite block 150 in place. This stage is preferably performed when the subject is sedated, but may alternatively be performed prior thereto.
[0086] Turning to FIG. 10D , it is seen that air exhaled orally by the subject, indicated by arrows, passes through the bore of tubular portion 156 , and is directed toward oral breath directing element 126 and oral prong 122 by the flaps 178 of flexible barrier 176 . Air that is exhaled nasally by the subject passes through nasal prongs 118 .
[0087] FIG. 10D illustrates the oral breath directing element 126 and the oral prong 122 being accommodated in groove 172 , such that a bottom surface of the oral breath directing element 126 engages transverse surface 173 of groove 172 . Additionally, if oral breath directing element 126 has been extended more than necessary for the facial features of the subject, the transverse surface 173 pushes the oral breath-directing element 126 hack until it is optimally positioned. The lips of the subject, indicated by reference numeral 192 preferably engage jaw engagement recesses 164 , and the top and bottom teeth of the subject, indicated by reference numerals 194 and 196 engage top and bottom teeth engagement surfaces 160 and 162 , respectively.
[0088] FIG. 10E illustrates the sedated subject, having the nasal prongs 118 of the oral nasal sampling cannula 110 in his nostrils and the endoscopic bite block 150 placed in his mouth and strapped to his head. Preferably, once the subject is sedated, oxygen is supplied to the nose of the subject via oxygen delivery openings 136 of oral nasal sampling cannula 110 , and to the mouth of the subject via oral oxygen delivery tube 142 and tubular portion 174 , as indicated by arrows. The oxygen is supplied to the oxygen delivery openings 136 via oxygen delivery bore 116 ( FIGS. 6A and 6B ) and to oral oxygen delivery tube 142 via oxygen delivery tube 138 and T-element 140 .
[0089] Turning to FIG. 10F , it is seen that when the subject is sedated, he tends to move or slump his head, thereby moving oral nasal sampling cannula 110 relative to bite block 150 , as indicated by angle α in the enlarged portion of FIG. 10F . The feature of the present invention which provides oral nasal sampling cannula 110 which is physically separated from bite block 150 and the placement of oral breath directing element 126 and oral prong 122 within groove 172 , ensure that even when the subject moves or slumps his head, the oral prong 122 and nasal prongs 118 will be maintained in their respective places, and accurate sampling will continue. Additionally, the placement of oral prong 122 within groove 172 provides a counter force to force applied by the subject's tongue to push at least the top portion of the bite block 150 out of the subject's mouth, thus ensuring accurate placement of the bite block.
[0090] As seen in FIG. 10G , an endoscope probe 198 is inserted into the bore of tubular portion 156 of bite block 150 , for performing the endoscopy procedure. During the insertion of endoscope probe 198 and its presence in the subject's mouth and pharynx, flaps 178 of flexible barrier 176 bend slightly inward to allow the passage of the endoscope probe 198 , as seen with particular clarity in the enlarged portion of FIG. 10G . However, the central opening 154 of bite block 150 remains substantially closed by flaps 178 , thereby separating the exhaled breath of the subject which is in bore of tubular portion 156 from the ambient air.
[0091] Additionally, the sampling may continue during the presence of the endoscope probe 198 in the pharynx of the subject, as the tubular portion 156 is of a slightly larger diameter than the central opening 154 , thereby ensuring that medical personnel have the space defined by the difference between heights H 2 and H 1 ( FIG. 8 ), as indicated by arrows in the enlarged portion of FIG. 10G .
[0092] It is appreciated that following the endoscopy, the bite block 150 may be removed from the subject's mouth, preferably by medical personnel. Prior to this stage, the valve 144 of oral oxygen delivery tube 142 is removed from tubular portion 174 thereby closing the valve and thus fully decoupling the oral nasal sampling cannula 110 from the endoscopic bite block 150 . However, the sampling of exhaled breath through nasal prongs 118 which remain in the subject's nostrils and through oral prong 122 which remains near the subject's mouth, preferably continues until the subject has awaken from the sedation. This is necessary because the subject's breath must be monitored as long as the subject is sedated.
[0093] Reference is now made to FIGS. 11A and 11B , which are simplified pictorial illustrations of an oral nasal sampling cannula forming part of an endoscopic bite block assembly, constructed and operative in accordance with yet another preferred embodiment of the present invention, in retracted and extended orientations respectively.
[0094] FIGS. 11A and 11B show an oral nasal sampling cannula 210 , which is adapted for collection of gases, such as carbon dioxide, exhaled by a subject, and for supplying oxygen to the subject.
[0095] The oral nasal sampling cannula 210 comprises a main body portion 212 , having formed therein an exhaled breath collection bore 214 and an oxygen delivery bore 216 . A pair of hollow nasal prongs 218 , which are adapted for insertion into the nostrils of the subject, is integrally formed with the main body portion 212 . A hollow oral prong 222 , which is formed with a limiting rib 223 and a cut-away tip 224 , is mounted onto a bottom surface of main body portion 212 . An oral breath directing element 226 , which is preferably in the shape of a cut-away tube, is slidably mounted onto oral prong 222 by a mounting portion 228 , and positioning of the oral breath directing element 226 is limited by the limiting rib 223 of oral prong 222 .
[0096] A channel formed in oral prong 222 is in fluid flow connection with channels formed in nasal prongs 218 , thereby forming a single junction 232 . Single junction 232 is in fluid flow communication with exhaled breath collection bore 214 , which in turn is in fluid flow communication with an exhaled breath collection tube 234 , which is adapted to be connected to a breath test analyzer or a capnograph (not shown), such as Microcap® which is commercially available from Oridion Medical LTD. of Jerusalem, Israel.
[0097] Main body portion 212 is formed with oxygen delivery openings 236 , which are in fluid flow communication with oxygen delivery bore 216 , which in turn is in fluid flow communication with an oxygen delivery tube 238 . Alternatively, at least one nasal oxygen delivery prong, adapted for insertion into the subject's nostril, may be used instead of oxygen delivery openings 236 . Oxygen delivery tube 238 is preferably formed with a T-element 240 , preferably terminating at an end thereof in a normally closed valve element 244 , which is preferably a luer valve. Oxygen delivery tube 238 is adapted to be connected to a source of oxygen (not shown).
[0098] Oxygen delivery tube 238 and exhaled breath collection tube 234 may optionally be placed around the ears of the subject, thereby stabilizing the oral nasal sampling cannula 210 on the subject's face, such that any movement of the subject will have negligible effect on the placement of the oral nasal sampling cannula 210 .
[0099] It is appreciated that oral breath directing element 226 may be in a retracted orientation as shown in FIG. 11A , or in an extended orientation as shown in FIG. 11B , thereby allowing the oral nasal sampling cannula 210 to be suited to the facial dimensions of the subject, resulting in more efficient collection of exhaled breath.
[0100] Reference is now made to FIGS. 12A and 12B , which are front-view and rear-view simplified pictorial illustrations of an endoscopic bite block forming part of an endoscopic bite block assembly constructed and operative in accordance with yet another preferred embodiment of the present invention and to FIG. 13 , which is a simplified sectional pictorial illustration thereof.
[0101] FIGS. 12A , 12 B and 13 show an endoscopic bite block 250 , which is adapted to be inserted into the mouth of a subject while the subject is sedated, to ensure that the mouth of the subject is maintained open during the endoscopy process, and that the subject does not interfere with the process by biting on medical instruments used.
[0102] The endoscopic bite block 250 includes a main body portion 252 , having formed therein a central opening 254 . A hollow tubular portion 256 extends distally from main body portion 252 , such that the opening of tubular portion 256 is an extension of central opening 254 . Central opening 254 is of a first height, indicated by H 1 in FIG. 13 , which is typically 16 to 20 mm in bite blocks for adult use, which is the height required by medical personnel for performing an endoscopy. In order to ensure that during breath sampling, oral prong 222 of oral nasal sampling cannula 210 ( FIGS. 11A and 11B ) does not interfere with the space required by medical personnel for performing the endoscopy procedure, the height of tubular portion 256 is greater than the height H 1 of central opening 254 as indicated by H 2 in FIG. 13 , and is typically 2 to 4 mm more than height H 1 (18 to 24 mm).
[0103] An outer surface 258 of tubular portion 256 is formed with top and bottom teeth engagement surfaces 260 and 262 , such that top teeth engagement surface 260 is relatively forward of bottom teeth engagement surface 262 . This structure facilitates easy and accurate biting of the bite block 250 by a subject, as it is suited to the jaw morphology of a closed human mouth. Surface 258 is additionally formed with jaw engagement recesses 264 , which are formed forwardly of teeth engagement surfaces 260 and 262 , respectively.
[0104] A top inner surface 270 of main body portion 252 is formed with a longitudinal groove 272 having a transverse surface 273 , which is adapted to accommodate oral prong 222 and oral breath directing element 226 of the oral nasal sampling cannula 210 ( FIGS. 12A and 12B ), as described with more detail hereinbelow with reference to FIG. 14 .
[0105] A tubular portion 274 is formed on a side of outer surface 258 of tubular portion 256 . Extending out of tubular portion 274 is an oral oxygen delivery tube 275 including a tip 276 , which is adapted to engage valve 244 ( FIGS. 11A and 11B ), thereby supplying oxygen directly to the oral cavity of the subject. Preferably, tip 276 comprises a luer corresponding to luer valve 244 . It is appreciated that tubular portion 274 is formed on outer surface 258 of tubular portion 256 , in order to ensure that the oral oxygen delivery does not interfere with the procedure performed by the medical personnel.
[0106] A flexible barrier 277 , preferably comprised of several flaps 278 , is disposed within central opening 254 , thereby substantially closing off the central opening and preventing dilution of exhaled breath by ambient air during sampling. An opening 280 is preferably maintained within flexible barrier 277 , thereby ensuring a small part of central opening 254 remains open in order to enable the subject to inhale external air. The flexible barrier 277 ensures that a majority of the subject's orally exhaled breath will be directed toward oral prong 222 ( FIGS. 11A and 11B ) thereby ensuring accurate sampling of the subject's breath. Opening 280 is preferably placed at a top part of central opening 254 near the cut-away tip 224 of oral prong 222 ( FIGS. 11A and 11B ), thereby directing and amplifying exhaled breath toward the oral prong 222 as it is the only substantial exit.
[0107] The flaps 278 are preferably formed of a plastic material selected to be of suitable thickness to maintain their position when undisturbed, yet bend readily when pushed by an endoscope probe, and thus do not limit the actions of the medical personnel performing the endoscopy. However, the flaps 278 preferably close back around the endoscope probe, thus maintaining a substantially closed oral cavity volume, and allowing most of the exchange of gases to occur close to the opening 280 of flexible barrier 277 , which opening is close to the cut-away tip 224 of oral prong 222 ( FIGS. 11A and 11B ) from which capnographic sampling can be performed accurately.
[0108] Additionally, the flaps 278 are preferably transparent, thus enabling medical personnel to see into the oral cavity during the endoscopy procedure.
[0109] Two attachment surfaces 282 , each formed with a slit 284 , extend horizontally outwardly from main body portion 252 . Slits 284 are adapted to connect to a band which is placed around the subject's head and is used to maintain the endoscopic bite block 250 firmly in position during the endoscopy procedure. Preferably, slits 284 are located above a horizontal centerline of main body portion 252 , such that the connected band will tend to exert a stronger pull to the top of the main body portion 252 , thus assisting in overcoming the subject's tendency to tilt the bite block 250 outward during the endoscopy procedure and in maintaining the bite block 250 upright in the subject's mouth.
[0110] Reference is now made to FIG. 14 , which is a simplified schematic illustration of the connection between the oral nasal sampling cannula of FIGS. 11A and 11B and the endoscopic bite block of FIGS. 12A-13 .
[0111] As seen in FIG. 14 , oral prong 222 of oral nasal sampling cannula 210 is accommodated within groove 272 of bite block 250 , such that a bottom surface of oral breath directing element 226 engages transverse surface 273 of the groove 272 . It is appreciated that transverse surface 273 is located below an inner surface of tubular portion 256 in order to ensure that air exhaled by the subject into tubular portion 256 will be directed toward groove 272 and oral prong 222 .
[0112] Additionally, tip 276 of oral oxygen delivery tube 275 engages valve 244 ( FIGS. 11A and 11B ) of T-element 240 of oral nasal sampling cannula 210 , thereby opening the valve 244 and forming a fluid flow engagement between oxygen delivery tube 238 and tubular portion 274 of endoscopic bite block 250 , which is in fluid flow engagement with the oral cavity of the subject.
[0113] Reference is now made to FIGS. 15A , 15 B, 15 C, 15 D, 15 E, 15 F and 15 G, which are pictorial illustrations of various stages of typical use of the endoscopic bite block assembly of FIGS. 11A-14 .
[0114] As seen in FIG. 15A , the nasal prongs 218 of the oral nasal sampling cannula 210 are placed in the subjects nostrils, preferably before the subject is sedated. Preferably, the exhaled breath collection tube 234 and the oxygen delivery tube 238 are placed around the subject's ears, in order to ensure the stability of the oral nasal sampling cannula 210 on the subject's face. As seen in the enlarged portion of FIG. 15A , at this stage the oral breath-directing element 226 is in its retracted orientation, indicated by the length H 3 .
[0115] At this stage, oral oxygen delivery tube 275 ( FIGS. 12A-13 ) is not connected to the T-element 240 of oral nasal sampling cannula 210 . However, even if oxygen is supplied to oral nasal sampling cannula 210 via oxygen delivery tube 238 , there is no oxygen leakage, as the T-element 240 is sealed by valve 244 .
[0116] Turning to FIG. 15B it is seen that the oral breath directing element 226 is extended to accommodate the facial dimensions of the subject, revealing part of oral prong 222 . Preferably, the oral breath-directing element 226 is moved down to a point in which a bottom end thereof is at the height of the top of the bottom lip of the subject, its new length being indicated by H 4 . This action is preferably preformed by medical personnel, but may alternatively be performed by the subject himself, a family member, or any other person.
[0117] FIG. 15C illustrates the insertion of bite block 250 into the mouth of the subject, such that main body portion 252 engages the outer surface of the subject's lips and the tubular portion 256 is inside the subject's mouth. Additionally, tip 276 of oral oxygen delivery tube 275 is inserted, preferably by medical personnel, into valve 244 of T-element 240 of oral nasal sampling cannula 210 , as indicated by an arrow in the enlarged portion of FIG. 15C , thereby opening the valve 244 .
[0118] A strap, indicated by reference numeral 290 , is attached to slits 284 of attachment surfaces 282 and is placed around the subject's head, thereby securing the bite block 250 in place. This stage is preferably performed when the subject is sedated, but may alternatively be performed prior thereto.
[0119] Turning to FIG. 15D , it is seen that air exhaled orally by the subject, indicated by arrows, passes through the bore of tubular portion 256 , and is directed toward oral breath directing element 226 and oral prong 222 by the flaps 278 of flexible bar 277 . Air that is exhaled nasally by the subject passes through nasal prongs 218 .
[0120] FIG. 15D illustrates the oral breath directing element 226 and the oral prong 222 being accommodated in groove 272 , such that a bottom surface of the oral breath directing element 226 engages transverse surface 273 of groove 272 . Additionally, if oral breath directing element 226 has been extended more than necessary for the facial features of the subject, the transverse surface 273 pushes the oral breath-directing element 226 back until it is optimally positioned. The lips of the subject, indicated by reference numeral 292 preferably engage jaw engagement recesses 264 , and the top and bottom teeth of the subject, indicated by reference numerals 294 and 296 engage top and bottom teeth engagement surfaces 260 and 262 , respectively.
[0121] FIG. 15E illustrates the sedated subject, having the nasal prongs 218 of the oral nasal sampling cannula 210 in his nostrils and the endoscopic bite block 250 placed in his mouth and strapped to his head. Preferably, once the subject is sedated, oxygen is supplied to the nose of the subject via oxygen delivery openings 236 of oral nasal sampling cannula 210 , and to the mouth of the subject via oral oxygen delivery tube 275 and tubular portion 274 , as indicated by arrows. The oxygen is supplied to the oxygen delivery openings 236 via oxygen delivery bore 216 ( FIGS. 11A and 11E ) and to oral oxygen delivery tube 275 via oxygen delivery tube 238 and T-element 240 .
[0122] Turning to FIG. 15F , it is seen that when the subject is sedated, he tends to move or slump his head, thereby moving oral nasal sampling cannula 210 relative to bite block 250 , as indicated by angle α in the enlarged portion of FIG. 15F . The feature of the present invention which provides oral nasal sampling cannula 210 which is physically separated from bite block 250 and the placement of oral breath directing element 226 and oral prong 222 within groove 272 , ensure that even when the subject moves or slumps his head, the oral prong 222 and nasal prongs 218 will be maintained in their respective places, and accurate sampling will continue. Additionally, the placement of oral prong 222 within groove 272 provides a counter force to force applied by the subject's tongue to push at least the top portion of the bite block 250 out of the subject's mouth, thus ensuring accurate placement of the bite block.
[0123] As seen in FIG. 15G , an endoscope probe 298 is inserted into the bore of tubular portion 256 of bite block 250 , for performing the endoscopy procedure. During the insertion of endoscope probe 298 and its presence in the subject's mouth and pharynx, flaps 278 of flexible barrier 277 bend slightly inward to allow the passage of the endoscope probe 298 , as seen with particular clarity in the enlarged portion of FIG. 15G . However, the central opening 254 of bite block 250 remains substantially closed by flaps 278 , thereby separating the exhaled breath of the subject which is in the bore of tubular portion 256 from the ambient air.
[0124] Additionally, the sampling may continue during the presence of the endoscope probe 298 in the pharynx of the subject, as the tubular portion 256 is of a slightly larger diameter than the central opening 254 , thereby ensuring that medical personnel have the space defined by the difference between heights H 2 and H 1 ( FIG. 13 ), as indicated by arrows in the enlarged portion of FIG. 15G .
[0125] It is appreciated that following the endoscopy the bite block 250 may be removed from the subject's mouth, preferably by medical personnel. Prior to this stage, the tip 276 of oral oxygen delivery tube 275 is removed from valve 244 ( FIGS. 11A and 11B ) of T-element 240 , thereby dosing the valve and fully decoupling the oral nasal sampling cannula 210 from the endoscopic bite block 250 . However, the sampling of exhaled breath through nasal prongs 218 which remain in the subject's nostrils and through oral prong 222 which remains near the subject's mouth, preferably continues until the subject has awaken from the sedation. This is necessary because the subject's breath must be monitored as long as the subject is sedated.
[0126] It is appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations, and subcombinations of various features described hereinabove as well as variations and modifications thereto which would occur to a person of skill in the art upon reading the above description and which are not in the prior art. | According to a preferred embodiment of the present invention there is provided a bite block assembly adapted for capnography and oxygen delivery to a subject, the bite block assembly ( 50 ) including a first capnography passageway adapted for passage therethrough of exhaled breath from the subject to a capnograph and a second oxygen delivery passageway, separate from the first passageway, adapted for passage therethrough of oxygen from an oxygen source to the mouth of the subject. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a multifunction signal switch suitable for use in a motor vehicle and, in particular, to a self-contained signal switch which is both rugged in construction and easy to maintain.
As exemplified by U.S. Pat. No. 3,858,176, multifunction switches such as turn signals and hazard warning devices are typically housed within the steering column of the vehicle. The size of the switch components is thus restricted and, as a consequence, the switch assemblies are susceptible to breakage when subjected to prolonged strenuous usage. The in-column switch assembly has therefore not found wide acceptance in heavy duty equipment. Similarly, it is difficult to perform maintenance upon a signal switch assembly that is built into the steering column because of the limited amount of space available in which to work. Normally, when such maintenance is required, the vehicle must be taken out of service for a period of time which, in the case of a heavy duty truck, can be costly.
To overcome some of the difficulties associated with the in-column signal switches, many heavy duty vehicle users have turned to the stronger and generally more reliable "hang on" or self-contained assemblies which can be clamped to the outside of the steering post. Although more accessible, these devices are still difficult to maintain because the electrical components, and particularly the switch contacts, are generally hard wired into the circuitry. Accordingly, changing contacts, which become worn with usage, require special maintenance that usually necessitates removal of the vehicle from service.
Most signal switch assemblies, whether self-contained or otherwise, only offer two modes of operation; a turn signal mode and a hazard warning mode. As a result, full advantage of the conveniently located signal switch is not truly realized.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to improve self-contained signal switches to provide for more reliable heavy duty service.
A further object of the present invention is to provide a rugged, easy to maintain, signal switch capable of delivering more than two functional modes of operation.
Another object of the present invention is to provide an automotive signal switch utilizing modular contacts that may be easily replaced in assembly.
These and other objects of the present invention are attained by means of a self-contained signal switch assembly that is adapted to be secured to the steering post of a motor vehicle and which includes a single actuator arm that is selectively positionable to provide three individual switching functions including a turn signal function, a hazard warning function and an optional function that can be selected by the user. Flexible blade contacts are utilized in the assembly that are packaged in modular units which can be easily replaced as required in assembly. The electrical system of the present device is further provided with a two lead pilot light that is compatible with either a two or three terminal flasher unit.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention as well as other objects and further features thereof, reference is had to the following detailed description of the invention to be read in conjunction with the accompanying drawings, wherein:
FIG. 1 is a perspective view of a signal switch apparatus embodying the teachings of the present invention showing the apparatus secured to the outside of the steering column of a motor vehicle;
FIG. 2 is an enlarged side elevation in section of the present signal switch assembly better illustrating component parts thereof;
FIG. 3 is a partial side elevation of the sectional view of FIG. 2 showing the actuating arm in a hazard warning mode of operation;
FIG. 4 is an enlarged plan view of the signal switch apparatus shown in FIG. 2 with the top cover removed;
FIG. 5 is a partial sectional view taken along lines 5--5 in FIG. 2 illustrating in greater detail the modular arrangement of the electrical contacts contained therein;
FIG. 6 is a partial view taken along lines 6--6 in FIG. 3 having parts omitted to more clearly show the contacts positioned in a hazard warning condition;
FIG. 7 is a breakaway sectional view showing the ball and detent arrangement for holding the lever arm of the apparatus in a number of manually selected functional positions;
FIG. 8 is a partial view of one of the contact modules being actuated by the actuating arm of the instant assembly; and
FIG. 9 is an electrical diagram setting out in schematic representation the electrical components of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring initially to FIG. 1 there is illustrated a heavy duty signal switch assembly 10 suitable for use in large trucks and other heavy duty vehicles normally requiring this type of rugged mechanism. The present signal switch is a "hang-on" installation which typically engages the steering column 11 of the vehicle by means of a clamp or the like (not shown) to support the assembly in a position wherein the operator of the vehicle can conveniently manipulate the actuating arm 12 without adversely affecting his control of the vehicle. The signal switch assembly is contained within a housing 13 that includes a base 14, having an inclined section 15, and a removable cover 16 situated over the base. A transparent lens assembly 17, made up of a central window 18 and two indicating arrows 19,20, is located in the top surface of the cover to provide a visual indication of the mode of operation selected by the operator.
The arm 12 passes out of the housing through means of an opening 21 that is provided in one side wall thereof. As best seen in FIGS. 2-5, the arm 12 is rotatably supported within the housing upon a pivot 22 staked into the base 14. A flat spring 24 of generally circular form is secured to a flange 25 carried upon the top surface of the arm 12 by any suitable means, as for example rivets 26. The spring 24 is provided with a hole 68 centrally formed therein having a close running fit with the undercut end of the pivot 22. In assembly, the flat spring is passed over the end of the pivot and is seated against the undercut shoulder to support the arm in a generally horizontal position. A clearance hole 27 is formed in the flange 25 of the arm through which the main body of the pivot passes. Sufficient clearance between the pivot and the arm is supplied so that the arm can be deflected in a generally vertical plane upon the flat spring while at the same time allowing the arm to be rotated in a horizontal direction. A pair of stops 29 extend upwardly from the top surface of the arm and are adapted, in assembly, to cooperate with the inner top wall of the housing cover to limit the vertical movement of the arm. Vertical deflection of the arm in a counterclockwise direction will cause the stops to contact the top wall of the cover and prevent further movement of the arm. As a result, the arm may only be deflected vertically in a clockwise direction as depicted by the phantom outline of the arm illustrated in FIGS. 2 and 3.
A detent mechanism, generally referenced 28, is also provided in conjunction with the arm to regulate horizontal positioning of the arm in assembly. The detent mechanism is made up of a plurality of balls 31, which are seated in openings formed in arcuate shaped sections 32 of the flat spring, and which cooperate with detent elements 33 depending downwardly from the top wall of cover 16. As best seen in FIG. 7, elements 33 contain a central detent notch 34 and two notch segments 35 and 36 respectively on either side thereof. The resilient flat spring and ball arrangement allows the arm to be horizontally repositioned between the three detent positions while at the same time supplying a sufficient biasing force to hold the arm in a selected position under heavy duty operating conditions. By the same token, this arrangement also permits the arm to be deflected in a vertical direction regardless of the detent position selected.
Referring now more specifically to FIGS. 4 and 5, there is illustrated two modular contact units 38 and 39 which serve to control the initiation of both the turn signal functions and the hazard warning function which will be explained in greater detail below. Each module contains a set of four flexible blades that includes one longer control blade 40 and three shorter follower blades 41-43. The central or body portion of the blades which make up the individual sets is supported within a rectangular spacer block 45 cast from an insulating material, such as a glass filled polyester, and which functions to maintain the blades in spaced parallel alignment in assembly. As shown, electrical contacts are supported at the free end of each blade which can be actuated, as will be explained below, to initiate or terminate certain electrical lighting functions.
The rectangular form of each spacer block is adapted to be seated within a holding frame 46 (FIG. 7) cast into the inner wall of the inclined section 15 of base 14. Each frame consists of two raised corner tabs 47,48 (FIG. 5) and two raised end tabs 49,50 which cooperate to receive the spacer block of a module therebetween and prevent the module from moving laterally in the housing. A spring loaded wire retainer 52 is rotatably supported upon post 51 situated between the two holding frames and the wire retainer is adapted to pass over the back of the spacer block of each module, as illustrated in FIGS. 4 and 5, to keep the units from moving out of the frame in assembly.
The terminal end of each blade in the module, that is, the end opposite the contact supporting end, is insertably receivable within plug in type socket assembly 53. The socket assembly forms part of an electrical harness, generally referenced 55, which includes a grommet 56, positioned within an opening provided in the lower part of the housing, and an insulating sleeve 57 through which passes a wire bundle 58 containing the electrical leads of the various related circuits. In practice, the sleeve is brought down the steering column of the vehicle and carried under the dashboard where the wires are electrically connected into the appropriate automotive circuits. The switch end of the leads are cast into the socket assembly as shown in FIG. 5. Each lead terminates at the socket face with a snap-in type receptacle 59 adapted to slidably receive the terminal ends of the contact blades therein and thus securely support the module units in place in assembly. To provide for interchangeability, equal spacing is maintained between the blades so that a single module can be used to service each contact set.
As can be seen, in the event one set of contacts needs replacing, the base is simply removed from the cover 16, which remains mounted upon the steering column, and the defective module unplugged from the socket assembly and a new module slipped into its place. Normally, the changeover can be accomplished by the operator of the vehicle in a matter of minutes using simple tools. As a consequence, a change of defective contacts can be made quickly while the vehicle is in use thereby avoiding the need of taking the vehicle out of operation.
The contact module 38 on the left-hand side of the housing, as viewed in FIG. 5, controls the operation of the front and rear warning lights on the right side of the vehicle while the contact module 39 controls the operation of the front and rear warning lights on the left-hand side. To initiate a right-hand turn signal, the arm is rotated in a horizontal plane about the pivot in a clockwise direction. This causes the detent balls to be moved out of the central detent notch and into notch segment 36. At the same time, a downwardly depending lug 30 supported upon the arm actively engages the contacts associated with contact module 38 to activate the lamps on the right-hand side of the vehicle. Rotating the arm in a counterclockwise direction, of course, will bring the lug into engagement with the contacts of module 39 and thus actuate the lamps on the left-hand side of the vehicle to generate a left-hand turn signal.
Referring to FIG. 8, there is shown a partial view of the arm positioned to signal a left-hand turn. As shown, the activating lug 30 engages a follower 60 supported on the longer or extended blade 40 of module 39 to deflect the blade back and thus open normally closed contact 61 and close the two normally opened contacts 62,63 which, as will be explained below, causes the warning lamps on the left-hand side of the vehicle to be flashed on and off. The detent mechanism noted above serves to hold the arm in the left turn operative position until such time as the operator manually returns the arm to its neutral position. This latter non-cancelling feature is desirable in many larger type vehicles having a relatively wide turning radius wherein the truck must swing wide in one direction before a turn in the opposite direction can be completed. This maneuver would normally cancel a conventional self-cancelling mechanism halfway through the turn and thus force the operator to reinitiate the turn signal while he is attempting to complete the turn.
Referring once again specifically to FIGS. 2 and 3, a slide, generally referenced 65, is slidably mounted within the actuator arm and is arranged to move back and forth over a reciprocal path of travel parallel with the central axis of the arm. The slide includes an outwardly depending pushbutton 66 at the left-hand end thereof as viewed in FIG. 2 that is adapted to pass through the unsupported end wall 67 of the arm and extend outwardly therefrom some distance to allow the operator of the vehicle to push the slide inwardly toward the housing. Preferably, the slide is fabricated of a resilient plastic material having a low coefficient of friction whereby the slide moves freely within the arm. The pivot 22, which supports the arm, passes upwardly through an elongated, axially aligned, opening 68 (FIG. 2) formed in the slide and also serves as a stop to govern the degree of lateral movement provided for the slide. A semicircular camming surface 69, which is formed on the right-hand end of the slide, is contoured so that its working face simultaneously engages both followers 60 on contact modules 38,39 to deflect the blades sufficiently to actuate the warning lamps on both sides of the vehicle when the slide is moved to a fully extended inward position as shown in FIG. 6. As will be explained below, this gang loading of the module contacts generates a flashing hazard warning signal. A slotted groove 70, centrally located in the camming surface, provides clearance for the downwardly extending actuating lug 30 affixed to arm 12.
A locking mechanism is operatively associated with the slide to hold the slide in the extended or hazard warning position when button 68 is pushed to a full in position. The holding mechanism includes a latch 72, depending downwardly from the slide, and a receiving notch 73 formed in the side wall of the housing. The latch normally extends downwardly beyond the level of the wall whereby the latch is forced upwardly as the slide is pushed toward the housing warning position. The latch is formed of the same resilient material as the slide and is therefore able to deform sufficiently to clear the wall. Upon clearing the wall, the latch immediately drops into the notch as shown in FIG. 3 to hold the camming surface in actuating contact against the contacts of the two modular units thus generating a continuous hazard warning signal.
A compression spring 75 is mounted horizontally within arm 12 and acts between the arm and the sleeve to urge the sleeve towards a home or non-actuating position. Two recesses 76,77 (FIG. 4) are formed in the side wall of the housing on either side of the latch receiving notch. The recesses are brought to a depth which will permit the latch to move out of the locked hazard warning position, under the urging of the compression spring, when the arm is rotated horizontally about the pivot to either side of its neutral position.
A pilot light 79 is mounted on the side of the arm as illustrated in FIG. 4. The light includes a lamp 80 and a shield 81 which are secured to the side wall of the arm to position the light directly below the indicator window lens 18, in the top cover of the housing, when the arm is in a neutral position. The location of the pilot light is offset in reference to the pivot of the arm such that the pilot light illuminates the appropriate arrow 19 or 20 when the lever arm is moved to a right or left-hand turn operative position. Electrical wiring to the lamp is brought into the housing via the harness as shown in FIG. 4.
The signal switch assembly of the present invention is also equipped with an additional switching function which can be wired into any one of a wide variety of automotive related electrical circuits at the option of the user. These circuits can include, but are in no way limited to, a horn actuating circuit, running light circuits or a headlight dimmer circuit. In the present apparatus, the arm is formed of a conductive material and is electrically grounded in assembly. An elongated switch contact 85 is positioned beneath the actuating lug 30 of the lever arm and, by means of the flat spring and detent arrangement as described above, the grounded lug is able to make the contact when the arm is deflected in a vertical direction. The lateral width of the contact is such as to permit the circuit to be closed regardless of the horizontal position of the arm. As a result, the operator is able to select the optional switch function when the arm is in a neutral position, an operative position or when the slide is extended inwardly. Again, the electrical wiring associated with the contact is carried out of the housing via the wiring harness as shown in FIG. 4.
Turning now to FIG. 9, there is shown an electrical diagram which will be used to describe the operational features of the present invention. In this diagram, the arm and slide are schematically represented as element 90 which can be activated in the manner described above to open and close the contacts of modules 38,39. Power to the electrical system is provided by the main automotive system which, for explanatory purposes, is depicted as a battery 91. As shown, the positive side of the battery is connected in series with a flasher circuit 92, brake switch 93 and relay circuit 94. The right rear warning lamps and right front warning lamps are represented by lights 95 and 96, respectively, while those on the left rear and front are represented by lights 97 and 98. The lamps, in this arrangement, are electrically grounded.
As is conventional, the brake switch is adapted to be closed by the operator depressing the brake pedal of the vehicle. Releasing the pedal causes the switch to be opened. The brake switch is electrically connected to normally closed contacts 61 and 100 contained in modules 39 and 38 so that the two rear warning lamps 95 and 97 are normally illuminated any time the brake pedal is depressed.
Flasher circuit 92 can be of any suitable construction and typically includes a transistorized switching network adapted to periodically open and close a control circuit at a predetermined rate to flash the warning lights on and off. The flasher circuit is electrically connected to the two normally opened contacts in both modular units which are represented as contacts 62 and 63 in module 39 and contacts 101 and 102 in module 38. As explained above, the arm, upon being manually rotated to an operative position on either side of its neutral position, opens the brake light contact of the engaged module and closes the flasher associated contacts thereby overriding the brake light function and generating a flashing turn signal on the appropriate side of the vehicle.
Pressing the button on the slide inwardly causes both modular contact units to be actuated simultaneously by the working face of the cam. This results in both brake light contacts 61,100 being opened and the four flasher contacts 62,63 and 101,102 to be closed thus generating a hazard warning signal wherein all warning lamps on both sides of the vehicle are brought into a periodic on-off function.
As further illustrated in FIG. 9, pilot light 80 is electrically shunted over the flasher control circuit 92. When the turn signal contacts are closed, a complete circuit from the battery to ground is provided through the flasher circuit, the pilot light and the closed contacts. Closing the flasher circuit puts a voltage on both sides of the pilot light causing the light to go off. Upon opening of the flasher circuit, most of the battery voltage is dropped over the pilot light thus turning the light on. Although the warning lights provide a path to ground for the pilot, they nevertheless remain unlit during the period that the pilot is illuminated because of the difference in resistance between the pilot bulb and the parallel wired warning lamps. As can be seen, this arrangement minimizes the amount of components required while still providing a system that is compatible with most two and three terminal flasher circuits.
Regardless of which position arm 12 is in, the arm can be deflected in a vertical plane to make the relay contact 85. This provides a path to ground for relay 94 causing the relay to become energized. In practice, the relay can be electrically connected into any one of a number of useful circuits at the option of the operator. As noted, these circuits can include, but are not limited, to a headlight dimming circuit, cab roof marker lights, side marker lights, fog lights, a horn actuator or the like.
As can be seen from the present disclosure, the apparatus of the present invention provides a rugged switch assembly that can be conveniently attached to the steering column of any type of motor vehicle to enable the operator to select a number of functions at his option. It should be further noted that the present device can be wired directly into any conventional flasher system using either a two or three terminal arrangement and can be easily assembled and disassembled for maintenance without having to dismantle the steering column of the vehicle. By utilizing plug in modular contact units, the down time involved for maintenance is further reduced thus affording the user substantial savings in time and money.
While this invention has been disclosed with reference to the details as set forth above, it is not confined to the details contained herein, and this application is intended to cover any modifications or changes as may come within the scope of the following claims. | A multifunction signal switch assembly suited for use in heavy duty trucks or the like requiring a rugged installation which can be readily dismantled and reassembled for convenient maintenance. The switch mechanism includes easily replaceable plug-in contact modules and a simple pilot light arrangement which renders the apparatus compatible with most standard two or three terminal flasher systems typicall used in the industry. The apparatus, in addition to the conventional turn signal and hazard warning functions, also supplies an additional function that can be wired, atthe user's option, into any number of automotive related circuits such as a headlight dimming circuit or the like. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention generally relates to methods for estimating a vehicle's feed-forward lateral acceleration and, more particularly, to methods using a measured parameter of the vehicle's steering system to refine a feed-forward lateral acceleration estimation technique.
[0003] 2. Description of Related Art
[0004] A vehicle develops an acceleration component lateral to the longitudinal axis of the vehicle when the vehicle begins to turn. During these situations it is normal in vehicles that provide an adjustability feature, to adjust the torque distribution between the wheels (front-to-back, side-to-side, etc.) in order to allow for effective handling of the vehicle. Lateral acceleration is one factor that is used in calculations that control the torque distribution amongst the wheels.
[0005] To enhance control response, it is advantageous to estimate the lateral acceleration of the vehicle from specific driver inputs. An estimated lateral acceleration may be used in a feed-forward control system to adjust for a condition caused by turning the vehicle, in combination with changing vehicle speed or alone, prior to the turn having a major affect on the stability of the vehicle. This estimated lateral acceleration is known as feed-forward lateral acceleration.
[0006] With reference to FIG. 3 , a known feed-forward lateral acceleration estimation method is schematically illustrated. In this known method, the measured vehicle speed 10 is input into a gain table 12 to arrive at a signal 14 that is lateral acceleration per degree of steering angle. In multiplier 17 the measured steering angle 16 is multiplied with the signal 14 to provide a lateral acceleration signal 18 , which is then converted to a magnitude value (by taking the absolute value 20 ) and its output is limited by passing this result through a saturation table 22 (to ensure the calculated value does not rise above actual vehicle cornering limits) to derive a normalized lateral acceleration signal 24 . In multiplier 29 , the normalized lateral acceleration signal 24 is multiplied by the sign of the steering angle, 26 , to arrive at the estimated feed-forward lateral acceleration signal 28 , which is used to control the front-to-rear and/or side-to-side torque applied to the vehicle wheels.
[0007] Unfortunately, in situations of low vehicle speed and tight turning, the known method for estimating feed-forward lateral acceleration become less accurate. More specifically, the feed-forward lateral acceleration is overestimated. It is believed that this overestimation is primarily due to the fact that the high turning angle (steering angle) tends to dominate the calculation. As a result, in a drive torque system utilizing feed-forward control, high rates of activation or shifting of drive torque may be implemented when they are, in fact, not required. Therefore, there exists a need in the art to correct the measured steering angle to compensate the feed-forward estimate of the lateral acceleration in low speed, tight turning situations.
SUMMARY OF THE INVENTION
[0008] The present invention is directed toward a method and apparatus for compensating for overestimations to feed-forward lateral acceleration estimates at low speeds and tight turning radii.
[0009] In accordance with the present invention, a correction factor based on a known quantity in the state of the art of vehicle dynamics is used. In one embodiment of the invention a method is provided that measures the speed of the moving vehicle, measures the steering angle of the moving vehicle, calculates an Ackerman steer angle of the moving vehicle, corrects the steering angle using the Ackerman steer angle, and finally calculates the feed-forward lateral acceleration of the vehicle using the speed of the vehicle and the corrected steering angle.
[0010] In further accordance with the present invention, the measured vehicle steering angle is corrected by subtracting the calculated Ackerman steer angle, and the so-corrected or adjusted vehicle steering angle is used to estimate the feed-forward lateral acceleration.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] These and further features of the invention will be apparent with reference to the following description and drawings, wherein:
[0012] FIG. 1 schematically illustrates a feed-forward lateral acceleration calculation technique using an Ackerman steer angle correction according to the present invention;
[0013] FIG. 2 is a schematic representation of the position of wheels on a vehicle during a turn; and,
[0014] FIG. 3 schematically illustrates a conventional feed-forward lateral acceleration estimating technique.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] As used in this description and in the appended claims, the following terms will have the definitions indicated thereafter:
“feed-forward lateral acceleration” means a calculated estimation of a vehicle's actual lateral acceleration (excluding any delays associated with the natural build-up of lateral acceleration following a steering angle input); “steering angle” means the angular displacement of the steering wheel itself by the driver; and “vehicle overall steering ratio” means the number of turns (rotations) of the steering wheel of the vehicle for one turn (rotation) of the vehicle road wheel about a vertical axis.
[0019] An improved method of calculating feed-forward lateral acceleration of a vehicle is provided. This improved method uses measurements of a vehicle speed and measurements of a vehicle steering angle, corrected using a calculated Ackerman steer angle, to calculate feed-forward lateral acceleration. The present invention provides an estimated feed-forward lateral acceleration that is more accurate, and minimizes or eliminates the problems of over-actuation from which the known methods suffer. Accordingly, the present invention, to be described hereafter in greater detail, provides greater accuracy, especially in situations when the vehicle is traveling at a low speed and making a tight turn.
[0020] Referring to FIG. 2 , the wheels 100 , 102 , 104 of a vehicle 106 are illustrated in a turning orientation. The wheels include a front left wheel 100 , a front right wheel 102 , and a pair of rear wheels 104 . As the vehicle 106 makes any type of turn, acceleration is created in a direction lateral to the vehicle's centerline 108 . This component, called lateral acceleration, is estimated by the method of the present invention, described hereinafter, and is used as part of a feed-forward control system to adjust the front-to-rear and side-to-side drive torque distribution to the wheels 100 , 102 , 104 for greater stability. As previously stated, feed-forward lateral acceleration estimation may lose its accuracy in conditions of low vehicle speed and tight turning. The improved estimation method and system of the present invention employs a correction factor to maintain accuracy.
[0021] With reference to FIG. 1 , the improved method of calculating or estimating feed-forward lateral acceleration is described. It is noted that although several of the components used in the improved method are identical to those used in the conventional method described hereinbefore with regard to FIG. 3 , these components are described in more detail hereinafter and given different reference numerals.
[0022] Readings of vehicle speed 200 and vehicle steering angle 202 are made. These readings are made by one or more sensors, as is known in the art. The sensed vehicle speed is input into a lookup table referred to hereinafter as a lateral acceleration gain table 204 . The lateral acceleration gain table includes values that are experimentally determined and serve to correlate input vehicle speed to lateral acceleration per steering angle degree. Therefore, the lateral acceleration gain table 204 serves to convert the measured vehicle speed into an anticipated or predicted lateral acceleration signal 206 , which has units of: (lateral acceleration)/(steering angle).
[0023] The output 206 of the lateral acceleration gain table 204 is supplied to a multiplier 208 , which also receives the corrected steering angle signal 210 , described hereinafter.
[0024] The vehicles measured steering angle 202 is reduced by the Ackerman steer angle 212 to arrive at the corrected steering angle. Calculation of the Ackerman steer angle 212 is described in more detail below.
[0025] Preferably, the measured steering angle 202 is corrected by subtracting the Ackerman steer angle 212 from the measured value in a subtraction block 214 to provide the corrected steering angle 210 . The corrected steering angle 210 is then multiplied by the predicted lateral acceleration gain signal 206 to provide a signal referred to hereinafter as the estimated lateral acceleration 216 . The absolute value of the estimated lateral acceleration is modified into a normalized lateral acceleration signal 218 by using a saturation table 220 .
[0026] The saturation table 220 contains values that are experimentally determined, and takes into account that the vehicle is not capable of generating lateral accelerations above a certain level due to natural tire adhesion limits. Therefore, the feed-forward lateral acceleration using the present method is reduced or limited so as not to produce lateral acceleration levels that are not physically possible from normal tire adhesion limits. Accordingly, the saturation table 220 includes a range of factors that vary based on the absolute value of the calculated lateral acceleration, 216 , prohibiting it from achieving a level that is not possible based on tire lateral adhesion. Rather than a simple saturation function (which assumes a 1:1 correspondence of the output to the input up to the saturation limit value) a shaping saturation function is used to allow progressive growth of the input parameter (calculated lateral acceleration) up to a defined maximum value.
[0027] The normalized lateral acceleration 218 output by the saturation table 220 is multiplied in the multiplier 221 by the sign of the corrected steering angle 210 to provide feed-forward lateral acceleration 222 . The feed-forward lateral acceleration 222 is used to adjust the front-to-back and/or side-to-side wheel torque distribution of the vehicle. Insofar as use of feed-forward lateral acceleration to adjust wheel torque distribution is known in the art, and is not part of the present invention, it will not be discussed further hereinafter.
[0028] With reference to FIG. 2 , for correct Ackerman steering the steer angle A i of the inner wheel 100 is greater than the steer angle A o of the outer wheel 102 , such that the axes 101 , 103 of the inner and outer wheels intersects at a single point 107 on the projection 105 of the rear axle. Accordingly, the Ackerman steer angle may be thought of the difference between the inner wheel steering angle A i and the outer wheel steering angle A o necessary to make the aforementioned condition exist. Although the Ackerman steer angle is considered to be known in the art, it will be described hereinafter to assist understanding of the disclosure.
[0029] The Ackerman steer angle δ may be referred to as the front road wheel input required to steer a normally front steer vehicle around a tight turn at or near zero velocity. The Ackerman steer angle of the vehicle may simply be defined as the vehicle's wheelbase divided by the turning radius of the vehicle. The turning radius of the vehicle may be described by other vehicle characteristics as follows:
R=V/Ψ
R=Vehicle turning radius V=Vehicle speed Ψ=Vehicle yaw rate
[0033] The yaw rate is estimated by known vehicle parameters in combination with other measured outputs of the vehicle, such as described below. Alternatively, the yaw rate may be measured by a yaw rate sensor. One way to estimate the yaw rate is as follows:
Ψ = 2 TR ⨯ ( V OUT - V IN )
Ψ=Vehicle Yaw Rate V OUT =Speed of outside wheel in a turn V IN =Speed of inside wheel in a turn TR=Vehicle Track Width
[0038] An estimate of the vehicle speed is the average of the speed of an inside wheel of the vehicle and an outside wheel of the vehicle, shown as follows:
V = 1 2 ⨯ ( V OUT + V IN )
[0039] The equations are rewritten in combination to provide a calculation for the Ackerman steer angle:
δ = 2 ⨯ L ⨯ ( V OUT - V IN ) TR ⨯ ( V OUT + V IN )
[0040] The equation for measuring the Ackerman steer angle may be scaled by the overall vehicle steer ratio thus allowing the Ackerman steer angle to be expressed in a manner that allows for direct correction of the measured steering angle:
δ = 2 ⨯ L ⨯ ( V OUT - V IN ) TR ⨯ ( V OUT + V IN ) ⨯ SR
δ=Ackerman steer angle V OUT =Speed of outside wheel in a turn V IN =Speed of inside wheel in a turn TR=Vehicle Track Width L=vehicle wheelbase SR=Vehicle overall steering ratio
[0047] In a preferred method of practicing the invention, a correction based on Ackerman steer angle 212 is limited with speed in order to mitigate any failure risk of certain sensors. Before applying the calculated Ackerman steer angle 212 to a correction of the measured steering angle 202 , the Ackerman steer angle 212 is passed through a speed-based correction permission table. Since correction is only required at speeds below a certain level a diminishing correction effect with increasing speed is created to ensure system failsafe robustness. For speeds below a certain value (40 kph), the Ackerman steer angle 212 is multiplied by “1” and fully used in correction. Within a speed range of 40-50 kph, the multiplying factor is gradually decreased to “0”, such that above 50 kph, the Ackerman steer angle 212 no longer takes effect.
[0048] The vehicle includes a number of sensors used to measure the parameters of the vehicle while in operation. A known speedometer is used to measure the overall speed of the vehicle. Velocity sensors that are part of known anti-lock braking systems (ABS) are used to measure individual wheel velocities. The vehicle's steering angle may be measured by a sensor in the steering column or by other known means.
[0049] Although the invention has been shown and described with reference to certain preferred and alternate embodiments, the invention is not limited to these specific embodiments. Minor variations and insubstantial differences in the various combinations of materials and methods of application may occur to those of ordinary skill in the art while remaining within the scope of the invention as claimed and equivalents. | A method of calculating feed-forward lateral acceleration of a moving vehicle is provided. The method includes the use of a corrected steering angle of the vehicle. The steering angle is corrected by using the Ackerman steer angle of the vehicle. Depending upon the speed at which the vehicle is traveling the steering angle may be corrected using the full Ackerman steer angle, a fraction of the Ackerman steer angle or not at all. | 1 |
This is a continuation of copending application(s) Ser. No. 07/972,887 filed on Nov. 6, 1992 as a file wrapper continuation of prior application Ser. No. 07/771,365 which was filed Oct. 1, 1991, both abandoned.
BACKGROUND OF THE INVENTION
This invention relates to an electric motor driven tool, and more particularly, to a power tool including a speed reduction mechanism for changing the revolution speed of a tool.
In general, there is known a power tool in which the tool is driven by an electric motor through a gear speed reduction mechanism comprising a plurality of stages of planetary speed reduction mechanisms, such electric motor and speed reduction mechanisms being arranged in a tool body. The power tool further includes a trigger switch for carrying out "ON" or "OFF" switching operations of the motor. The tool is driven and rotated in a desired operation mode by operating the trigger switch.
In a conventional power tool of the character described above, the rotation speed of an output shaft of a gear speed reduction mechanism driven by an electric motor is switched from a low speed to a high speed or vice versa to thereby drive the tool with variable rotation speeds.
One example of such a power tool including a speed reduction mechanism is disclosed in Japanese Patent Laid-open Publications No. 61-209883 and No. 62-224584.
The speed reduction mechanism disclosed in these prior art references includes a slide gear member provided with an internal gear engaged with a plurality of planetary gears of the speed reduction mechanism. The slide gear member is disposed to be movable in its rotation axis direction and is supported to be rotatable or non-rotatable in accordance with its moved positions.
In a conventional power tool, an arcuate swing member is connected to such a slide gear member in a manner that the slide gear member can be moved by swinging the swing member by means of a speed change lever. Two kinds of speed reduction ratios can be obtained in accordance with the difference between the rotation speeds of the planet gears at both the rotation stop time of the slide gear member and the rotating time of the internal gear by the operation of the speed change lever, whereby a desired speed reduction operation can be performed.
In the conventional power tool of the described type, however, the slide gear member is moved by the swinging motion of the swing member, and moreover, since the swing member is formed so as to have an arcuate configuration, the swing member is subjected to an expansion deformation when a load is applied thereto. Thus, there causes a case in which the smooth motion of the slide gear member is not expected, resulting in less reliability of the speed changing operation. Furthermore, the requirement for the location of the speed change lever and the swing member will result in the increasing of the constructional members or parts as well as troublesome manufacturing workings thereof.
SUMMARY OF THE INVENTION
An object of the present invention is to substantially eliminate defects or drawbacks encountered in the prior art and to provide a power tool having a structure capable of smoothly changing a driving speed with an improved reliability.
Another object of the present invention is to provide a power tool having improved speed reduction gear arrangements capable of smoothly changing the engagement thereof for a high and a low speed driving operations of the tool.
These and other objects can be achieved according to this invention by providing a power tool comprising: a tool body to which a tool is mounted; a driving motor incorporated in the tool body and having an output shaft; a motor operating mechanism incorporated in the tool body for operating the driving motor; a speed reduction gear mechanism including a plurality of stages of planetary gear arrangements for transmitting a driving force of the driving motor to the tool to drive the same; a s 1 ida gear member disposed in the tool body to be axially movable therein, the slide gear member being provided with an internal gear to be meshed with planet gears of the planetary gear arrangement and adapted to change revolution speed of the speed reduction mechanism; and a movable member operatively connected to the slide gear member for moving the slide gear member, the movable member having a ring shape and being disposed on an outer side of the slide gear member.
In preferred embodiments, the slide gear member is constructed to be rotatable in a high speed driving operation and to be non-rotatable in a low speed driving operation. The movable member comprises a resilient support ring having a slide lever having an operating portion exposed outward of the tool body. A cylindrical gear case is further disposed on an output side of the motor in the tool body with a space from an inner surface of the tool body, the support ring being disposed in the space to be axially movable, the slide lever being integrally formed with the support ring.
The motor operating mechanism comprises a trigger switch for carrying out an ON-OFF switching operation of the motor, a rotation change lever operatively connected to the trigger switch to change rotation direction of the motor and a battery detachably mounted to the tool body for supplying an electric power to the motor.
The cylindrical gear case is disposed in the tool body and the speed reduction gear mechanism substantially disposed in the gear case comprises a first, a second and a third stages of planetary gear arrangements, the first stage planetary gear arrangement comprising a first sun gear mounted to the output shaft of the motor, a plurality of first stage planet gears meshed with a first sun gear and with an internal gear formed on the gear case, and a first support plate having one side surface on which are projected a plurality of pins to which the first stage planet gears are rotatably supported, respectively, the second stage planetary gear arrangement comprising a second sun gear integrally disposed on another side surface of the first support plate, a plurality of second stage planet gears meshed with a second sun gear and with an internal gear of the slide gear member, and a second support plate having one side surface on which are projected a plurality of pins to which the second stage planet gears are rotatably supported, the second support plate being provided with an external gear which is meshed with the internal gear of the slide gear member in accordance with an axial movement thereof; and the third stage planetary gear arrangement comprising a third sun gear integrally disposed on another side surface of the second support plate, a plurality of third stage planet gears meshed with the third sun gear and with an internal gear formed on the gear case, and a third support plate having one side surface on which are projected a plurality of pins to which the third stage planet gears are rotatably supported, the third support plate being secured to an external gear formed on the spindle shaft in a spline engagement.
According to the power tool having the characteristics described above, the annular support ring is axially movable by the operation of the slide lever which is easily operated by an operator. The slide gear is positioned by this movement in a rotatable or non-rotatable position to thereby carry out the desired driving speed changing operation. Accordingly, in a case where any load is applied to the support ring, the support ring can be prevented from deforming, whereby the slide gear member can be smoothly moved, resulting in the improvement of the speed changing reliability. This change of the driving speed can be surely transmitted to the spindle shaft through the driving speed reduction mechanism including improved planetary gear arrangements.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of this invention and to show how the same is carried out, reference is first made, by way of preferred embodiments, to the accompanying drawings, in which:
FIG. 1 is a longitudinal sectional view of a power tool according to the present invention;
FIG. 2 is a sectional view showing a gear arrangement of the power tool of FIG. 1 in a low speed operation thereof;
FIG. 3 is a sectional view similar to FIG. 2, showing the gear arrangement in a high speed operation;
FIG. 4 is a lateral sectional view of FIG. 2;
FIG. 5 is an explanatory view showing a function of a support ring; and
FIGS. 6(a), 6(b) and 6(c) are a front, a plan and a side, partially in section, views of one example of the support ring.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2 showing one embodiment of a power tool according to this invention, a power tool comprises a hand-grip pistol-type tool body 1 provided with a cylinder portion 1a, a hand-grip portion 1b and a grip end portion 1c. In the cylinder portion 1a of the tool body 1, is disposed an electric motor 2 having an output shaft 2a, and a substantially cylindrical gear case 3 is disposed on the side of the output shaft 2a, the right side as viewed in FIG. 1, with a predetermined space between the gear case 3 and the inner surface of the tool body 1.
An output pinion 4 is mounted on the output shaft 2a and a plurality of planet gears 5 constituting a first stage planetary reduction mechanism are meshed with the output pinion 4. The output pinion 4 may be called a first sun gear. These planet gears 5 are supported to be rotatable by pins 7 projected from one side of a first stage support plate 6. On the other side of this first stage support plate 6, a second sun gear 8 of a second stage planetary reduction mechanism is integrally formed. The gear case 3 is provided, on its inner surface, with an internal gear 9 with which the respective planet gears 5 are meshed.
The second sun gear 8 of the second reduction mechanism is meshed with a plurality of planet gears 12 rotatably supported by pins 11 projected from one side of a second stage support plate 10 having an outer periphery to which an external gear 10a is formed. A third sun gear 13 of a third stage planetary reduction mechanism is integrally formed to the other side of the second stage support plate 10.
A plurality of third planet gears 14 are meshed with the third stage sun gear 13, and on the outer side of the respective planet gears 14 is arranged an internal gear 15 which stationarily abuts against the gear case 3 so that the internal gear 15 is meshed with the planet gears 14. The respective planet gears 14 are arranged to be rotatable about pins 15 secured to a third stage support plate 16. An inside portion 16a of the third stage support plate 16 is secured to an external gear 18a formed on a spindle shaft 18 through a spline engagement. As shown in FIG. 2, the spindle shaft 18 has a front end portion 18b to which a chuck 20 (FIG. 1) for mounting a desired tool is mounted. As described above, the gear speed reduction mechanism is comprised of the first, second and third stage planet gears, sun gears and support plates for rotating and driving the tool.
An annular support ring 21 formed of a material such as resin, rubber or metal (e.g., iron and spring steel) having a resiliency or springy property is arranged to be movable in a predetermined space formed between the inner surface of the tool body 1 and the outer surface of the gear case 3. A slide lever 22 is arranged outside, on the upper side as viewed in FIG. 2, of the support ring 21 in a manner that an upper operating portion 22a of the slide lever 22 is exposed outwardly of the tool body 1 in a state as shown in FIGS. 6(a) to 6(c).
Projections 23 serving as engaging pieces are formed, as shown in FIGS. 4 and 6(a), on both the upper and lower edge portions of the slide lever 22, and the tool body 1 is provided with recessed portions 24 for receiving the projections 23 in engagement therewith at predetermined low and high speed operating positions of the tool body 1. A pair of guide pins 25 are formed on both side portions of the support ring 21 so as to project inwardly. The guide pins 25 extend so as to penetrate guide holes 26 axially formed in both the side portions of the gear case 3 towards the inside of the gear case 3.
A slide gear member 27 is provided with an internal gear 27a meshed with the planet gears 12 and is arranged to be axially movably inside the gear case 3 at a portion corresponding to the outside portion of the planet gears 12 meshed with the second stage sun gear 8. The slide gear member 27 is provided with an annular recessed portion 27c to which the inner end of the guide pins 25 of the support ring 21 are fitted to thereby rotate the slide gear member 27. A plurality of projections 28 are formed at a portion near the internal gear 9 of the gear case 3 and a plurality of recessed portions 29 are also formed on the outer peripheral surface of the slide gear member 27 so that the projections 28 are engageable with the recessed portions 29.
When the slide lever 22 is operated, in FIG. 4, so that the engaging projection 23 thereof is engaged with the recessed portion 24 of the tool body 1, the support ring 21 is displaced in the axial direction. According to this axial displacement of the support ring 21, the guide pin 25 now engaging with the annular recess 27c of the slide gear member 27 is moved along the guide hole 26 of the gear case 3, and the slide gear member 27 is hence moved along the axial direction. When the slide gear member 27 is moved rearwardly and the engaging projections 28 of the gear case 3 are then engaged with the recessed portions 29 of the slide gear member 27, the slide gear member 27 is inhibited in its rotation and maintains its stationary state and the support plate 10 is rotated at a low speed as shown in FIG. 2. Accordingly, FIG. 2 represents a low speed driving operation.
In the meantime, when the slide gear member 27 is moved forwardly and the engagement between the recessed portions 29 of the slide gear member 27 and the engaging projections 28 of the gear case 3 is released, the slide gear member 27 is made rotatable. The engagement of the external gear 10a of the support plate 10 with the internal gear 27a of the slide gear member 27 allows the second sun gear 8 and the planet gears 12 and the support plate 10 to rotate together, thus the support plate 10 being rotated at a high speed as shown in FIG. 3. Accordingly, FIG. 3 represents a high speed driving operation.
Reference is now made back to FIG. 1, in which a switch unit 30 for controlling the switching of the operation of the motor 2 is accommodated in the hand-grip portion 1b of the tool body 1 below the motor 2, and a battery 31 for supplying an electric power to the motor 2 is detachably mounted to the grip end portion 1c of the tool body 1.
A trigger switch 32 is incorporated in the tool body 1 in an electrical connection with the switch unit 30 for carrying out switching operation, i.e. ON or OFF switching operation, of the switch unit 30. A rotation change lever 33 for changing the rotating direction of the motor 2 is disposed in the tool body 1 above the trigger switch 32, and the rotation change lever 33 is pivoted about a pivot pin 34 disposed at the central portion of the lever 33. On both sides of the front end of the rotation switch lever 33 are integrally formed operation projections 35, respectively, so as to project outward from both the sides of the tool body 1.
In an actual operation of the power tool of the present embodiment, an operator grips the hand-grip portion 1b and presses forwardly the operation projections 35 with a finger of the operator, whereby the rotation change lever 33 is operated to rotate the switch unit 30 through a rotation switch pin thereof.
The power tool of the structure described above will operate as follows.
First, as shown in FIG. 2, in a case where the power tool is driven at a low driving speed, the slide lever 22 is shifted rearward, leftward as viewed in FIG. 2, to engage the engaging projection 23 with the recessed portion 24 (FIG. 4) Of the tool body 1 for carrying out the low speed operation, and the slide gear member 27 is then moved to engage the recessed portions 29 of the slide gear member 27 with the engaging projections 28 of the gear case 3 to thereby maintain the slide gear member 27 to a non-rotatable state.
The operator holds the hand-grip portion 1b of the tool body 1 and pulls the trigger switch 32 to turn on the switch unit 30. The switch unit 30 then generates a signal to the motor 2 to drive the same. The rotation driving force of the motor 2 is transmitted to the spindle shaft 18 in a speed reduced manner through the output pinion 4, the respective stage planet gears 5, 12, 14, and the sun gears 8, 13, whereby the tool mounted to the chuck 20 is rotated to carry out the predetermined working. During this low speed operation, since the slide gear member 27 is secured in a non-rotatable manner, the second stage planet gears 12 are rotated with the teeth thereof being meshed with the teeth of the internal gear of the slide gear member 27 in the stationary state, thus increasing the speed reduction ratio and hence the spindle shaft 18 is rotated with a reduced speed.
On the contrary, as shown in FIG. 3, in a case where the power tool is operated with a high rotation speed, the slide lever 22 is shifted frontward, i.e. rightward as viewed in FIG. 3, to engage the engaging projection 23 with the recessed portion 24 (FIG. 4) of the tool body 1. In the next step, by moving the slide gear member 27, the recessed portions 29 of the slide gear member 27 is released from the engaging projections 28 of the gear case 3, and the internal gear 27a of the slide gear member 27 is meshed with the external gear 10a of the support plate 10, whereby the slide gear member 27, support plate 10 and the sun gear 8 are integrally operated, thus maintaining the slide gear member 27 in a rotatable state.
With this state, when the operator operates the trigger switch 32, the motor 2 is driven through the switch unit 30, and the rotation driving force from the motor 2 is transmitted to the spindle shaft 18 through the output pinion 4, the respective stage planet gears 5, 12, 14 and the sun gears 8 and 13 at a high rotation speed. During this high speed operation, since the slide gear member 27 is in the rotatable state, the slide gear member 27 is rotated together with the second stage planet gears 12, the sun gear 8 and the support plate 10, thus decreasing the speed reduction ratio, whereby the spindle shaft 18 is rotated at a high speed.
Therefore, as described above, according to the power tool of the present invention, the operation of the power tool can be easily switched to a high or low rotating speed.
Referring to FIG. 5, when the slide lever 22 is shifted, there may cause a case where the slide gear member 27 fails to be engaged with the teeth of the planetary gears 12. In such a case, however, since the support ring 21 is formed of a springy material, the engagement therebetween can be achieved by the springy property of the support ring 21 when the motor 2 is driven.
Since the operation change lever 33 is operated by the operator by pressing the operation projections 35, the switch unit 30 can be operated in the reversible manner, thus switching the rotating direct/on of the driving motor 2.
As described above, according to the present invention, since the support ring 21 is formed in a ring shape and disposed axially movably to carry out the speed changing operation, the deformation of the support ring 21 can be surely prevented even in a case where a load is applied to the support ring 21, resulting in the smooth movement of the slide gear member 27 and hence remarkably improving the speed changing reliance. Moreover, since the slide lever 22 is integrally formed with the support ring 21, the number of tile parts or elements can be reduced as well as easy manufacturing thereof.
It is to be understood that the present invention is not limited to the described embodiment and many other changes and modifications may be made without departing from the scope of the appended claim. | A power tool has a speed reduction gear mechanism including a plurality of stages of planetary gear arrangements, a slide gear member disposed in a tool body to be axially movable therein to change revolution speed of the speed reduction mechanism, and a movable member operatively connected to the slide gear member for moving the same, the movable member having a ring shape and being disposed on an outer side of the slide gear member whereby the slide gear member can be smoothly moved. | 1 |
This is a division of application Ser. No. 473,260, filed May 24, 1974.
BACKGROUND OF THE INVENTION
This invention relates to an improved apparatus for production of synthetic multifilamentary yarns having uniform quality from high molecular weight linear polymers, in particular polyesters, according to an improved melt spinning process.
An important area of use of such synthetic multifilamentary yarns is the production of tire cord. A number of high polymers are well suited for this utility, especially polyesters and polyamides; however, in the following description reference will be made particularly to filaments of polyethylene terephthalate.
Since tire cord and the structures formed from it are among the essential construction elements for the safety and useful life of a tire, high quality requirements are naturally placed on such endless filaments. In view of the alternating stretching and compression stresses which tires experience in operation, a necessary precondition for the use of synthetic multifilamentary yarns for tire cord is an adequate fatigue resistance of the filaments. For optimum results, it is critical that the individual filaments be substantially uniform. Accordingly, it is common practice to determine the coefficient of variation of the evenness of the yarn (U %) using an Uster evenness tester as manufactured by the Zellweger Company of Uster, Switzerland, and described in "Handbood of Textile Testing and Quality Control" by E. Groover and D. S. Hamby.
Polyethylene terephthalate has come into strong prominence in the last few years for use in tire cord production. Polyethylene terephthalate unfortunately undergoes a considerable thermal decomposition between the conclusion of the production of the spinning raw material (raw polymer melt) and its subsequent shaping into threads. This thermal decomposition can be reduced if the molten spinning raw material is maintained for as short a time and at as low a temperature as possible. However, the residence time of the spinning melt in the spinning apparatus is prescribed by the dimensions of the apparatus, and the lower limit of the spinning temperature is determined by the highly undesirable condition of melt fracture. Where melt fracture occurs, the spun, unstretched filaments do not have a smooth or even surface, and exhibit fluctuations in diameter which are unacceptable for use in tire cord.
It is evident from this that the spinning requirements are diametrically opposed. On the one hand, low melt temperature is required for low decomposition, and on the other hand, high spinning temperature is required for trouble-free spinning. It has been suggested that this problem may be overcome by supplying the polymer melt for melt spinning at a temperature below the spinning temperature and heating the melt prior to filament formation. Normally, the required increase in the temperature of the melt is accomplished by use of a spinning assembly that includes a spinning filter disposed upstream of the spinneret plate, the pressure drop across said spinning filter being at least about 150 atmospheres.
Unfortunately, the polyester yarn made in accordance with known processes is not completely satisfactory. In particular, fused filaments and excessive variation in the evenness of filaments (U %) has been noted when the polymer melt is extruded through the spinneret at a rate of about 50 pounds per hour or greater. Problems in fiber uniformity have been particularly troublesome in so-called double-end melt spinning of synthetic fibers, i.e., using one spin pot to feed both sides of a "split" spinneret. Accordingly, research has been continued in an effort to solve these deficiencies.
SUMMARY OF THE INVENTION
The present invention relates to an improved apparatus for preparing synthetic multifilamentary yarns having uniform quality. The process may be summarized as follows:
In a process for the production of a synthetic multifilamentary yarn from a high-molecular weight thermoplastic polymer, selected from the group consisting of linear polyester and polyamide polymers, by melt-spinning, including the steps of supplying a melt of said polymer at a temperature below the spinning temperature, and heating the melt to spinning temperature prior to filament formation, the improvement which comprises:
a. extruding the molten synthetic polymer at a rate of at least 50 pounds per hour downwardly through a spinneret having a plurality of extrusion orifices.
b. advancing the extruded filaments downwardly through a substantially stationary column of air having a temperature of 100° to 330°C. immediately below the spinneret, the average distance between adjacent filaments immediately below the spinneret being at least 0.24 inch, preferably 0.28 to 0.4 inch; and
c. subsequently advancing the filaments downwardly through a quenching zone wherein they are in contact with cooling air introduced into the path of the filaments, said air contacting said filaments transverse, countercurrent and cocurrent in progressive order of their movement through said quenching zone, said air contacting the filaments at a volumetric rate of 100 to 800 cubic feet of air per pound of filaments entering the quenching zone.
The apparatus for carrying out the process of the present invention comprises a spinning unit comprising a spinning pump, a spinneret, and a spinning filter disposed between said pump and said spinneret, for extruding a plurality of filaments downwardly into a heated sleeve, the wall of said heated sleeve being imperforate and secured to the spinneret in an air-tight manner, said heated sleeve leading downwardly in an air-tight manner, said heated sleeve leading downwardly to a quenching chamber having an inlet and an outlet for allowing cooling air to pass through the chamber and means for regulating the stream of cooling air passing through said chamber whereby both the volumetric rate of the air stream and its general direction as it contacts the descending plurality of filaments may be regulated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic front view of the preferred apparatus used for the process of this invention.
FIG. 2 is a schematic side view of the preferred apparatus used for the process of this invention.
FIG. 3 is a perspective view of the quenching chimney labeled 6 in FIGS. 1 and 2, parts having been broken away to reveal details of construction.
FIG. 4 is a schematic of a two end embodiment of the draw panel labeled 9 in FIGS. 1 and 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
It has now been found that synthetic multifilament yarn, e.g., polyethylene terephthalate multifilament yarn, including such yarn of high denier per filament, e.g., 20 to 50 denier per filament (undrawn) can be melt spun continuously at high production rates such as 50 to 90 pounds per hour, and this yarn can be continuously drawn without an intermediate step of winding up, at draw ratios of at least 4:1. These results are achieved in accordance with this invention, by employing a controlled quenching of the melt spun filaments under critical conditions whereby the coefficient of variation of the evenness of the yarn (U %) is not above 10. More specifically, in accordance with the present process, a relatively large number of heavy filaments are extruded downwardly into a substantially stationary column of air having a temperature of 100° to 330°C. and a height of from 0.5 to 2 feet, preferably 1 to 1.5 feet, immediately below the spinneret, the distance between adjacent filaments immediately below the spinneret being preferably 0.28 to 0.4 inch, and subsequently advancing the filaments through a quenching zone wherein they are contacted with cooling air entering the zone at a volumetric flow rate of 100 to 800, preferably 200 to 700 cubic feet of air (measured at standard temperature and pressure) per pound of entering filaments, the air being at inlet temperature preferably not above 35°C. Especially effective is a split flow of air in the cooling zone, said air contacting the filaments transverse, countercurrent, and cocurrent in progressive order of their movement through the quenching zone, whereby the temperature of said filaments is reduced to not over 55°C.
One preferred embodiment of this invention is directed to an improved melt spinning process and apparatus involving double-end spin-draw and take-up for multifilament synthetic polymer fibers. The accompanying drawings illustrate the preferred apparatus.
Referring to FIGS. 1 and 2, like numbers indicate like apparatus. Molten polymer is fed by extruder 1 to spinning pump 2 which feeds spinning block 3 containing a conventional spinning pot, not shown, including a spinneret and a spinning filter disposed between said spinning pump and said spinneret. The spinning pot spinneret is divided into two parts by means of an undrilled stripe wide enough to form a visible stripe between the two multifilament continuous ends 4 and 5. Said multifilament continuous ends 4 and 5 are extruded from the spinneret at a rate of at least 50 pounds per hour, preferably 50-90 pounds per hour, and are passed downwardly through a heated sleeve 15 immediately below the lower part of the spinneret. The heated sleeve has a baffle 16 forming an inwardly extending flange at the end of the heated sleeve remote from the spinneret to minimize the flow of cooling air into the heated sleeve. The two multifilament continuous ends are cooled in quenching chimney 6 (described hereinafter and shown in FIG. 3), pass over finish roll 7 through two guides 8 to draw panel 9 (described hereinafter and shown in FIG. 4). Then the two ends, 4 and 5 pass to winder 10 through transverse guide, not shown, mounted on a cam in cam housing 11 which traverses the yarn across drive roll 12 which drives chucks 13 and 14 by surface driving a package of yarn. Each end is separately wound up on chucks 13 and 14.
As previously mentioned, FIG. 3 shows a preferred embodiment of quenching chimney 6 shown in FIGS. 1 and 2. The multifilament continuous ends 4 and 5 pass downwardly from the heated sleeve 15 through heated sleeve baffle 16 directly into the top of quenching chimney 6. Quenching chimney 6 is an elongated chimney at least 60 inches in height, preferably 60 to 80 inches in height, which is rectangular in cross-section and provided with imperforate top, rear, and side walls. The front of the chimney is partially covered by an imperforate door 31 which terminates short of the top of the wall and presents an open passage for air discharging from the chimney 6. At the lower rear side thereof, the quenching chimney 6 communicates with a duct 32 through which quenching air at substantially room temperature is introduced. The interior of quenching chimney 6 is partitioned by a perforated distribution plate 34 and a distribution screen 35, which forms the boundary between a plenum chamber 36, to which air is introduced from inlet duct 32, and a quenching chamber 37 through which the multifilament continuous ends 4 and 5 pass. In the top portion of quenching chamber 37 above door 31, provision is made for a plurality, preferably 2 to 5, parallel baffles 38 of shaped profile which form sections 39 intended to provide guided travel of the air stream transverse to the movement of the multifilament continuous ends 4 and 5 through said top portion of quenching chamber 37. The multifilament continuous ends 4 and 5 pass through the length of quenching chamber 37 and leave the quenching chamber, preferably through a shaped baffle 33 at the bottom of said chamber. The quenching air enters the plenum chamber 36 through duct 32, passes through distribution plate 34 and distribution screen 35 to the quenching chamber 37. The direction of air flow in quenching chamber 37 is indicated by arrows in FIG. 2 and FIG. 3. As shown by these arrows, the quenching air preferably contacts the filaments, transverse, countercurrent, and cocurrent in the progressive order of their movement through the quenching chamber 37. Preferably, 2 to 5 parallel baffles 38 are used; however the baffle requirement depends somewhat on the denier produced and the throughput as shown in the specific examples.
FIG. 4 shows the preferred embodiment for a two end embodiment for the draw panel 9 shown in FIGS. 1 and 2. Yarn passes from the quenching chimney 6 to a pretension roll 21 with its accompanying separator roll 21a, then into first feed roll pair Godet rolls 22 and 23, then through the draw point localizer 29 which can be a conventional heated pin or a steam jet, then to a draw roll pair of Godet rolls 24 and 25, then to a relaxation pair of Godet rolls 26 and 27 and optionally through an entangling apparatus such as a conventional steam or air operated interlacing jet, and on to winder 10 as shown in FIGS. 1 and 2.
It is important that the above-described process and apparatus of the present invention permits a significant increase in production capacity of a polymer spinning operation. In some cases, it is practical to convert a single-end fiber plant to double-end plant with only simple changes in the original equipment, the yarn production being increased for example by a factor of 2. Also, the present invention substantially overcomes problems of poor yarn quality such as the formation of loose filament loops and broken filaments. Further, the present invention greatly improves the mechanical quality problems of double-end spinning caused by fused, filaments and filament irregularity in undrawn filaments.
In order to demonstrate the invention, the following examples are given. They are provided for illustrative purposes only and are not to be construed as limiting the scope of the invention, which is defined by the appended claims. In these examples, parts and percentages are by weight unless otherwise indicated. The intrinsic viscosity of the polyester is given as a measure for the mean molecular weight, whcih is determined by standard procedures wherein the concentration of the measuring solution amounts to 0.5 g/100 ml., the solvent is a 60 percent phenol-40 percent tetrachloroethane mixture, and the measuring temperature is 25°C. In the examples, the diameter fluctuations along an unstretched bundle of filaments serve as a measure of uniformity. For high quality yarn, it is important that the filaments be substantially uniform. Accordingly, the coefficient of variation of the evenness (U %) is determined using an Uster evenness tester manufactured by the Zellweger Company of Uster, Switzerland and described in "Handbood of Textile Testing and Quality Control" by E. Groover and D. S. Hamby.
EXAMPLE 1
A melt of polyethylene terephthalate having an intrinsic viscosity of about 0.92 was supplied at a rate of 60 pounds per hour, at a temperature of about 291°C., to the apparatus shown in FIGS. 1 to 4. The molten polymer was fed by extruder 1 to spinning pump 2 which fed spinning block 3 containing a conventional spinning pot comprising a spinning filter and a spinneret, the spinning filter being disposed between the spinning pump and the spinneret. The spinning filter consisted of a conventional sieve filter combination of 24 metal screen layers. The pressure drop through said spinning filter averaged 200 to 400 atmospheres. The spinning pot was enclosed in a controlled high temperature atmosphere so that loss of heat from the polymer was minimized. The melt enthalpy increase through the pump and sieve filter was sufficient to heat the melt at a point immediately above the spinneret to about 305°-310°C., and the pressure at this point was about 50 atmospheres. The flow of polymer through the spinneret was maintained at a constant rate of 60 pounds per hour by spinning pump 2.
The spinning pot spinneret was divided into two parts by means of an undrilled "stripe" wide enough to form a visible split between the multiple ends below the spinneret. The spinneret was preferably positioned with respect to the quenching chimney 6 so that the stripe was parallel to the side walls of said chimney and therefore to the flow of cooling air through the top portion of said chimney. The spinneret plate had 384 holes (192 holes on each side of the undrilled stripe), each of 0.018 inch diameter, spaced so that the distance between the filaments formed was 0.28 to 0.40 inch immediately below the spinneret.
From said spinneret there was extruded two ends of multifilament, continuous filament yarn, and the two ends were passed downwardly into a substantially stationary column of air contained in a heated sleeve 15, about 15 inches in height, disposed surrounding and immediately beneath the spinneret. The air temperature in the heated sleeve was maintained at about 300°C. at the top of the sleeve, decreasing to about 115°C. at the bottom. The temperature of the metal in the heated sleeve was about 330°C. at the top and 220°C. at the bottom of the sleeve. The minimum distance between filaments at the bottom of the heated sleeve was about 0.24 inches. A heated sleeve baffle 16 was provided at the bottom of the heated sleeve forming an inwardly extending flange to minimize flow of cooling air into the heated sleeve.
Yarn leaving the heated sleeve was passed directly into the top of quenching chimney 6, shown in detail in FIG. 3. The quenching chimney was an elongated chimney 70 inches in height, substantially rectangular in cross-section and provided with imperforate top, rear and side walls. The front of the chimney was partially covered by an imperforate door 31 which terminated about 17.5 inches short of the top wall and presented an open passage for air discharging from the chimney. The interior of the quenching chimney was partitioned by a perforated distribution plate 34 and distribution screen 35, which formed the boundary between plenum chamber 36 and quenching chamber 37. Quenching air at about 25°C. and 65% relative humidity was supplied to plenum chamber 36 from inlet duct 32, at about 200 cubic feet of air per pound of filaments entering the quenching chamber 37.
The two ends of multifilament, continuous filament yarn were advanced downwardly through quenching chamber 37 wherein they were in contact with the cooling air introduced into the path of the filaments. Four horizontal parallel baffles 38 approximately 3 inches apart vertically and extending down about 12 inches from the top of quenching chamber 37 were used to provide transverse contact of the cooling air with the filaments in the top portion of the quenching chamber. In the middle portion of the quenching chamber below the horizontal baffles 38, the cooling air was deflected upward by imperforate door 31 and flowed substantially countercurrent to the movement of the filaments, said air leaving the quenching chamber via the opening above imperforate door 31. Part of the cooling air flowed out of the bottom of the quenching chamber with the filaments, and the air flow in the bottom zone of the quenching chamber was substantially cocurrent to the movement of the filaments. This novel quenching system increased quenching efficiency significantly as evidenced by air temperature and air velocity profiles. The number of horizontal stack baffles 38 required to obtain improved undrawn yarn quality was preferably 2 to 5 as shown in Example 2. The temperature of the cooled yarn at the bottom of quenching chamber 37 was about 50°C. In the present example, where polyester was supplied at 60 pounds per hour, 4 parallel horizontal baffles 38 gave high quality yarn; the coefficient of variation of the evenness of the undrawn yarn (U %) was not above 10 over an extended period of operation.
The two ends of cooled, multifilament continuous filament yarn were advanced downwardly, preferably through a shaped baffle 33 at the bottom of quenching chamber 37. The ends were separated by guides 8 located below a lubricating finish applicator 7. Following lubrication, the ends passed through a guide separation to pretension roll 21 with its accompanying separator roll 21a, shown in FIG. 4. The yarn was then passed over cold feed roll pair Godet rolls 22 and 23, then through a draw point localizer which was a conventional steam jet, then to a draw roll pair of Godet rolls 24 and 25 operated at about 145°C. and traveling at a speed 5.0 to 6.6 times faster than the feed roll, then to a relaxation pair of Godet rolls 26 and 27, and optionally through an entangling apparatus such as a conventional air operated interlacing jet, and on to winder 10 to shown in FIGS. 1 and 2. Typical yarn prepared at a draw ratio of 6 had the following properties:
Denier 1,000Tenacity, g/d 9.25Elongation, % 13.5Shrinkage, % 9.5
It will be understood that the above-described draw panel can be modified if desired. For example, the yarn may be drawn on a seven roll panel or on a four roll panel. However, regardless of panel set up, the draw panel process steps involve pretensioning to provide yarn stability on the rolls and on entry of the yarn into the draw point localizer steam jet, feed rolls to provide constant yarn supply to the draw zone, a draw point localizer to provide draw-down point in the draw zone, draw rolls to maintain constant draw ratio and relax rolls to provide for control of yarn physical properties. Optionally, a yarn compaction jet may be used before or after the relax rolls to provide yarn entanglement.
EXAMPLE 2
A series of tests were carried out to produce yarn using the process and apparatus for Example 1 but modifying various factors to show the criticality of the process and apparatus elements required to produce high quality yarn, particularly yarn wherein the coefficient of variation of the evenness of the undrawn yarn (U %) is not above 10. Most important effect noted was the interaction effect resulting when the cooling air introduced into the path of the filaments contacts the filaments transverse, countercurrent and cocurrent in progressive order of their movement through the quenching chamber. With use of the preferred apparatus, the air flow was easily controlled by adjusting the height and position of the imperforate door 31 and the number and position of the parallel baffles 38 at the top portion of quenching chamber 37. Particularly desirable results were obtained by a combination wherein the imperforate door 31 blocked 70-80%, preferably about 75% of the lower part of the front of the quenching chamber 2 to 5 horizontal baffles 38 were used in the top portion of the quenching chamber. The following table indicates the criticality of various elements. In these tests, the standard deviation (σ) of the Uster value (U %) was about 1.0%, and a difference of 3% or more between values is significant at greater than the 99% level.
TABLE I______________________________________Quenching Chamber Trials(1,000 Denier Yarn at 60 Pounds/Hour Throughput)Number ofBaffles (HeatedSleeve Baffle Door Uster ValueUsed) Blockage (U %)______________________________________None Lower 75% 251 Lower 75% 142 Lower 75% 93 Lower 75% 94 Lower 75% 85 Lower 75% 8None Lower 75% 24None Open 14None (with Heated Lower 75% 31Sleeve Baffle Removed)______________________________________
These data show that improved yarn (low U%) resulted when the heating sleeve baffle was used, the lower 75% of the front of the quenching chamber was blocked, and 2 to 5 horizontal baffles 38 were used in the top portion of the quenching chamber. In additional tests, similar results were shown for 1,000 denier yarn at 53 pounds/hour throughput. For 1,000 denier and 1,300 denier yarn at 80 pounds/hour throughput, optimum Uster (U %) was obtained using 4 baffles located 3, 6, 12 and 18 inches from the top of the quenching chamber with a baffle 33 at the bottom of the quenching chamber. This same baffle arrangement was also applicable to 1,000 and 1,300 denier yarns at lower throughputs.
EXAMPLE 3
The apparatus shown in FIGS. 1 and 2 supplied 60 pounds/hour e-polycaprolactam to a spinning pot enclosed in a controlled high temperature environment. The spinning pot spinneret was divided into two parts by means of an undrilled stripe wide enough to form a visible split between the multiple ends below the spinneret. The average distance between adjacent filaments immediately below the spinneret was 0.28 to 0.4 inch. The ends were advanced downwardly through a substantially stationary column of air maintained at 100° to 330°C. in heated sleeve 15. The ends were then advanced downwardly through quenching chimney 6 wherein they were contacted with cooling air introduced into the path of the filaments, said air at 25°C. contacting the filaments transverse, countercurrent and cocurrent in progressive order of their movement through the quenching chimney 6. The air contacted the filaments at a volumetric rate of about 200-300 cubic feet of air per pound of filaments entering the quenching chimney 6. The ends were separated by guides 8 located below a finish applicator 7. After lubrication, the ends passed through a guide separation and onto a heated feed roll and accompanying idler roll. Feed roll temperature was maintained at 80 ± 10°C. The yarn ends were then passed around a first stage draw roll and accompanying idler roll at a peripheral speed 2.5- 4.0 greater than the feed roll. The draw roll temperature was kept below 50°C. (Optionally a heated draw pin at 65°-85°C. is placed between the feed and first stage draw rolls.) The yarn ends were then directed to a draw point localizer. The ends were then passed around a heated roll and accompanying idler roll at 125°-210°C., which operated at a peripheral speed 1.4-2.3 times that of the first stage draw roll. The yarn was then taken up on a multi-end winder.
DISCUSSION
In additional tests, we have shown that conventional crossflow quenching of polyester and polyamide yarn is satisfactory for relatively low filament counts of say less than 200 filaments and relatively low throughputs of less than 35 pounds per hour through the spinneret. However, for increased production capacity, e.g., 50 to 90 pounds per hour through the spinneret, and particularly for double-end production requiring a total of for example 380-400 filaments, standard quenching was found inadequate as indicated by fused filaments and poor filament uniformity. We have found that the quenching chamber baffles described in the present disclosure when used in combination with a heated sleeve baffle and a partially blocked quenching chamber door, gave the improved quenching efficiency required. Blocking the door of the quenching chamber below the baffled area forced a much greater percentage of cooling air to be carried through the yarn in the zone just below the heated sleeve removing more heat, causing the yarn to be blown in a steady arch, and permitting higher air rates while improving yarn quality. Major advantages gained by the present invention include improved filament uniformity, elimination of fused filaments, improved air velocity profiles and improved quench air temperature profiles. Smoke tests were utilized to show that as the filaments were advanced downwardly through the quenching zone, the cooling air contacts said filaments transverse, countercurrent, and cocurrent in progressive order of their movement through the quenching zone.
The present invention is particularly useful for economical production of polyamide and polyester tire and industrial yarn. By "polyamide" is meant the polymers made by condensation of diamines with dibasic acids or by polymerization of lactams or amino acids, resulting in a synthetic resin characterized by the recurring group --COHN--. The preferred polyesters are the linear terephthalate polyesters, i.e., polyesters of a glycol containing from 2 to 20 carbon atoms and a dicarboxylic acid component containing at least about 75% terephthalic acid. The remainder, if any, of the dicarboxylic acid component may be any suitable dicarboxylic acid such as sebacic acid, adipic acid, isophthalic acid, sulfonyl-4,4'-dibenzoic acid, or 2,8-di-benzofuran-dicarboxylic acid. The glycols may contain more than two carbon atoms in the chain, e.g., diethylene glycol, butylene glycol, decamethylene glycol, and bis-1,4-(hydroxymethyl) cyclohexane. Examples of linear terephthalate polyesters which may be employed include poly(ethylene terephthalate), poly(butylene terephthalate), poly(ethylene terephthalate/ 5-chloroisophthalate) (85/15), poly(ethylene terephthalate/5-[sodium sulfo]isophthalate) (97/3), poly(cyclohexane-1,4-dimethylene terephthalate), and poly(cyclohexane-1,4-dimethylene terephthalate/hexahydroterephthalate) (75/25). | An improved process and apparatus for production of synthetic multifilamentary yarns having uniform quality. The method comprises extruding a molten synthetic polymer downwardly through a spinneret, advancing the extruded filaments downwardly through a substantially stationary column of heated air, and subsequently advancing the filaments downwardly through a quenching zone wherein they are in contact with cooling air introduced into the path of the filaments under controlled conditions of air velocity and direction of flow. The apparatus for carrying out the process comprises an extrusion spinneret for extruding a number of filaments directly into a heated sleeve having walls that are imperforate, said heated sleeve leading to a quenching chamber having opposite, essentially vertical inlet and outlet panels for allowing cooling air to pass through the chamber, and means for regulating the stream of cooling air whereby both the velocity of the air stream going through the quenching chamber and its general direction as it contacts the descending filaments may be regulated. | 3 |
BACKGROUND
The present invention relates to shower drains, such as are often used in residential, commercial, and institutional shower constructions.
Typical tiled showers must by code and design have a slope that moves the water from all floor surfaces to the drain. A normal shower configuration would be a square, rectangle, or a polygon. Those configurations mandate four or more triangular shaped quadrants all converging at the drain. Modern day designs have mandated larger overall size showers and more complex base configurations. The larger the shower foot print, the longer the slope. However, these configurations cause problems as noted below.
Each sector of these polygons creates an intersecting plane that creates problems for the setting of tile on the base. Even with small tile or stone (2″×2″), these changes in plane make the finished floor show these changes in plane, which can be aesthetically unacceptable and further can lead to leak problems at lines of intersection. For example, historically the drain is most often placed at the common vertex of these polygons. With the design world trending to larger format tile, the setting of tile with intersecting planes creates a virtually impossible situation for the tile setter due the changes in plane. In addition, many designs go to single slabs of stone for the shower base. This creates a problem for the installation since all drains are designed to be parallel to the subfloor.
A trench drain at the outboard side of one of the peripheral sides of the configuration can solve this problem. It is still necessary to provide the appropriate slope as listed in the plumbing code. However, since the intersecting planes have been eliminated, the size tile used as a finished surface is now not a factor. This opens up the options in both the design and materials that can be used.
Trench drains have been used in outdoor applications by the construction industry for many years. The most common usage is slab on grade applications, such as at the edge of parking lots and building entrances. These applications do not require 100% leak integrity since the ground fill surrounding the drain absorbs any leakage that occurs. These type trench drains are typically manufactured in a variety of linear processes in plastic and various metals. The drain is cut and assembled in sections with end caps at the ends of a run.
While the concept for shower trench drains is similar, the requirement that the installation be 100% waterproof is mandated by code. Since the vast majority of applications are over occupied space, the watertight integrity of the drain system is critical and flood testing is required by most plumbing codes.
There are some existing trench drains for buildings. Most are constructed of variety of grades of stainless steel, and include drain bodies constructed from combinations of cut segments welded together or stampings with additionally welded components. Due to the large number of sizes required by the design community, the ability to build multiple size dies for the drain bodies is not cost effective. Thus, components in known existing trench drain configurations are typically welded. However, welding is expensive and can lead to leak problems. For example, many times welding is the cause for small undetectable leaks that lead to water problems in the field that will not be noticed for many years, at a time when they have already created considerable problems such as rotted under-floor structures and smells associated with wet moldy environments. Notably, leaks can occur at the welds either at the time of manufacture, or during or after installation. These leaks can increase over time (or show up for a first time), due to corrosion and/or stress during installation and/or fatigue and/or from material stress caused in part by the welding. Quality control of welding is difficult, time consuming, and can add considerably to manufacturing expense, particularly where the welding extends 360 degrees around a pipe or connection. It is noted that shower trench drains are unforgiving, in that the water being drained away will find all leaks, and will eventually cause a problem.
Additionally, most known shower trench drains have trench bodies that are made of sheet metal formed with multi-angled surfaces, making them difficult to accurately position during an installation. Specifically, every trench body must have a specific slope for adequate water drainage. The mandated slope in the trench body (with constant wall thickness) leaves a bottom of the drain body on an angle to the drain opening. This occurs since the sheet material of known trench bodies has a uniform constant wall thickness. This factor leads to difficult installations since the drain body needs to be supported by dry packed mortar (or adjustable jacks that are left in the mortar bed) at a perfect sloped angle. It is not easy to form dry packed mortar at a perfect sloped angle, as required to support the known shower trench drain bodies. Molded trench drains also have a similar problem. Specifically, trench drains that are molded from thermoplastic materials effectively have the same issues since constant-thickness wall design is a typical requirement for injected molded designs.
Known existing trench drains are commonly constructed in straight length configurations from 24 to 72 inches. Whether the drain is made from metal or plastic material, the costs to tool the numerous sizes is often cost prohibitive. Complex configurations other than straight are generally too complex to fabricate in metal, except by welding as noted above, since their low volume manufacture makes it cost prohibitive to invest in expensive capital-intensive tooling.
SUMMARY OF THE PRESENT INVENTION
In one aspect of the present invention, a shower trench drain apparatus includes a water collecting trench drain body with a block of material compatible with approved plumbing materials and codes and that is formed to include a drain channel with angled bottom surface.
In another aspect of the present invention, a shower trench drain apparatus comprises a water collecting trench drain body including a block of material having a flat bottom adapted for horizontal installation and an integrally-formed up-facing drain channel with angled bottom surface.
In another aspect of the present invention, a shower trench drain apparatus includes a shower trench drain body of polymeric material having an integrally-formed drain channel with angled bottom surface and drain opening, a waterproof membrane over the drain body, a clamp ring retaining the membrane to the drain body, and a grate adjustably retained to the drain body by a height adjustment mechanism.
In another aspect of the present invention, a method of constructing a shower trench drain apparatus comprises steps of forming a shower trench drain body of polymeric material including a flat bottom surface, an integrally-formed drain channel with angled bottom surface and a drain opening. The method further includes steps of supporting the body on a flat support surface in an installation, laying a waterproof membrane over the drain body, clamping the membrane onto the body using a clamp ring, and attaching a grate adjustably to the drain body with an adjusted height that matches a final floor surface of a shower.
The present system has several advantages including: very waterproof (especially given a lack of welds on metal drain components), foolproof in terms of installation, cost effective given the few and simple components, mates well with existing shower drain systems. The trench body made by a formed plastic block is seen as a real advantage given the low volume of these parts, since it can be manufactured on a just-in-time basis (which minimizes inventory cost and tooling investment), such as by being machined with CNC equipment.
These and other aspects, objects, and features of the present invention will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is an exploded perspective view of the present shower trench drain apparatus; and FIG. 2 is a side cross sectional view of an assembly of the components in FIG. 1 .
FIGS. 2A , 3 - 6 are perspective, top, side, bottom, and end views of the assembled shower trench drain assembly of FIGS. 1-2 .
FIGS. 7 and 8 are cross sections taken along lines VII-VII and VIII-VIII in FIGS. 3 and 4 , respectively.
FIG. 9 is a perspective view of an end of a shower trench drain assembly.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present shower trench drain apparatus includes a trench body constructed from a single block of material machined to its final shape including various integral features. It is contemplated that the material will typically be selected to be a polymer such as PVC (Poly Vinyl Chloride) or ABS (Acrylonitrile butadiene styrene). A reason is because these materials are capable of being machined in addition to being compatible with common types of rigid pipe used in the plumbing industry. Further, it is noted that PVC and ABS materials are widely available in large format sheets with many available thicknesses. This allows the construction of complex design shapes by CNC machining with the only limitation being the overall dimension of the raw block. The present inventive concepts are based in part on the premise that it is far more cost effective (for manufacturing, installation, and durability reasons) to design and manufacture configurations into a block of material than it is to cut, stamp and (reliably) weld an even walled metal material of constant thickness. Notably, the present trench body has a flat horizontal bottom surface, which greatly facilitates installation since preparation of the supporting material for the trench drain body (i.e., mortar or other material) only requires making it horizontally level/flat, as noted below.
Since the drain is formed from a single block of plastic, the configurations are only limited to creativity of the designer. This allows for the ability to create complex polygons with multiple drain slopes and drain openings. CAD (Computer Assisted Design) and CAM (Computer Assisted Manufacturing) make design and manufacturing very feasible. In addition, the PVC and ABS materials used in the drain construction are able to be directly solvent welded (or adhesively bonded) to common rough in drain pipes. This eliminates the need for special adapters to connect the drain body to the rough in drain pipe. This is potentially very important, since solvent welding (and adhesively bonding) can create very high quality and easily formed joints that are leak-proof and with high long-term reliability of the absence of leaks.
The present apparatus incorporates a flat bottom surface on the drain body itself. This allows for direct mechanical attachment to the subfloor without the need for leveling mechanisms or shims or jacks found in conventional metal trench drains. In addition this eliminates the need to cut away the subfloor in order to allow for the code mandated slope on the drain interior.
The present apparatus can be used in both mortar bed and thin-bed applications since the drain bottom is always flat. Since many thicknesses of tile and stone are available, this invention incorporates the feature of multiple standoffs to adjust the finish drain cover to the same plane as the top of the drain cover. This is critical to the final appearance of the shower floor and the function of the drain. It can adjustably accommodate the additional thickness for the material that is used to bond the tile to the shower floor substrate.
Additionally, the present apparatus can incorporate a pre-drain strainer that collects soap residue, hair and other matter that is not collected by the finish cover or grate. The pre-drain strainer can be constructed of plastic or metal and is located prior the drain opening. It incorporates a series of holes that allow for the water to pass through to the drain hole, but collect any foreign matter that makes it to that point. This feature allows for cleaning foreign matter from the drain by just removing the drain cover, and clearing or dumping the pre-drain strainer. This feature also reduces the frequency of need for using a plumbers snake to clean the system. It also reduces maintenance issues in both residential and large commercial applications.
Since watertight integrity is needed any all shower applications, the present apparatus incorporates a mechanism for sealing and mechanically locking the waterproof membrane to the drain body. The design includes a continuous channel of a semi-circular configuration formed on the top of the trench drain body adjacent to the perimeter of the water collection containment portion of the drain body. This channel is filled with an appropriate waterproof elastomeric sealant. NobleSealant 150 is an example of a proper sealant. A stainless steel clamping ring seal is fastened to the drain body by the means of small self tapping stainless steel screws. The section of material below the clamping ring is depressed to create a downward flow of drain water to the collection chamber of the drain body.
The waters exit point (i.e., drain outlet opening) is generally in the center of the collection chamber, but can be placed at any point in the collection chamber as long as the slope directs the water to the exit point. The illustrated drain body has an exit point constructed in a manner that allows the rough in drain pipe to be solvent welded to the drain body without the use of separate plastic fittings.
A drain cover (or grate) of typically stainless steel covers the water collection chamber. The drain cover is shaped in a c-channel configuration to improve its rigidity. It is both functional and decorative and can be constructed with openings and patterns forming unique/aesthetic designs and finishes. A number of integral standoff bosses are incorporated into the collection chamber of the body. Stainless steel screws adjustably engage these bosses allow the strainer cover to be brought level to the finish floor. After the cover is properly adjusted to the proper height, additional screws are used to mechanically fasten the cover to the drain body and fix its height.
In regard to the drawings, the illustrated shower trench drain assembly 20 ( FIGS. 1-2 ) includes a shower trench drain body 21 , a waterproof sheet liner 22 , a clamp ring 23 , and a cover or grate 24 . The drain body 21 is placed at a side of the shower floor and embedded to be flush with a slightly-angled planar floor. The drain body 21 is a relatively-thick block of plastic material, such as 1-4″ high, 4-6″ wide if it is straight drain design, and several inches long, such as 6 to 96 inches, and is PVC or ABS or similar plastic. The slab is substantially free of stress so that the block does not warp when machined, nor warp over time after installation. (Stress free blocks of PVC and ABS are commercially available.) A clamp ring recess 25 is formed around and into a top of the block, and a drain channel 26 is also formed into the top. The clamp ring recess 25 is configured to receive a sealant material or a gasket to create a pliable permanent seal around the opening cut into the sheet liner 22 over the drain channel 26 in drain body 21 , and cooperates with the mechanical clamp mechanism to further assure a leak-proof assembly and installation. The drain channel 26 includes an angled bottom surface that angles toward a center drain hole 28 and a plurality of screw-receiving bosses 29 are formed around edges of the drain channel 26 . Pilot holes are drilled in the drain body to receive self tapping standoff screws. A sheet of water proof material liner 22 is placed on the drain body 21 and extends across the entire shower floor. The clamp ring 23 clamps the liner 22 onto the drain body 21 . An inside area is cut away to expose the drain channel 26 . The grate 24 includes welded-on components 32 with holes through which threaded screws 33 are extended and that extend downward to mechanically hold the cover in place. (It is noted that the welded-on components 32 are above the liner 22 and inside the channel of the body 21 , such that they cannot cause a water leak problem.) The drain cover height adjustment screws 33 engage the holes 30 . A top surface of the grate 24 lies flush to a shower floor once ceramic tiles 36 are installed on the shower floor.
FIGS. 2A , 3 - 6 are perspective, top, side, bottom, and end views of the assembled shower trench drain assembly 20 , and FIGS. 7 and 8 are cross sections taken along lines VII-VII and VIII-VIII in FIGS. 3 and 4 .
FIG. 9 is a perspective view of an end of a shower trench drain assembly 20 . Illustrated is a clamp ring 23 held in place with screws, and a grate 24 held to the bosses 29 with separate screws. The grate 24 is supported above the remainder of the assembly, so that its top surface is flush with the shower floor once ceramic tiles are installed.
It is contemplated that the present inventive apparatus can include additional features and accessories, such as a pre-drain strainer 35 that fits into slotted weir holder 37 . The pre-drain strainer 35 ( FIGS. 1-2 ) can be constructed of plastic or metal, and is located prior the drain opening. It incorporates a series of holes that allow for the water to pass through to the drain hole, but that allow the strainer to collect any foreign matter that makes it to that point. This feature allows for cleaning foreign matter from the drain by just removing the drain cover. This feature also reduces the frequency of need for using a plumbers snake to clean the system set into the channel 26 . The strainer 35 can have a shape similar to the channel 26 and be similar in length (or shorter). It would be hidden under the cover or grate 24 , but would be easily removable upon removing the cover. Alternatively, it is contemplated that arrangements could be made so that the strainer set into the cover and was removable without first removing the cover.
Notably, it is contemplated that a scope of the present invention includes any manufacturing method or process of manufacture for forming the trench body, such as by injection molding, casting, or other manner. Further, it is contemplated that a scope of the present invention includes any unitary trench body as formed with flat bottom or with cored standoffs and integral sloped water-channeling surface, regardless of the manufacturing method.
It is to be understood that variations and modifications can be made on the aforementioned structure without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise. | A shower trench drain apparatus includes a shower trench drain body of polymeric material having an integrally-formed drain channel with angled bottom surface and drain opening or openings, a waterproof membrane over the drain body, a clamp ring retaining the membrane to the drain body, and a grate adjustably retained to the drain body by a height adjustment mechanism. The trench drain body formed from a block of material such as PVC or ABS, which are compatible with approved plumbing materials and codes. The block has a flat bottom adapted for horizontal support during installation and includes integrally-formed features facilitating adjustment during installation while minimizing components and separate parts and simplicity of installation. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method for the treatment of diabetes, which method produces excellent effect of reducing insulin resistance.
[0003] 2. Background Art
[0004] Type II diabetes is a disease exhibiting anomalous glucose tolerance; i.e., high insulin resistance, and the number of patients of diabetes has increased in recent years as a result of lifestyle-related factors such as obesity and overeating. Such patients currently number 7,400,000 in Japan and 150,000,000 throughout the world, and will probably reach 300,000,000 in 2005. Insulin resistance is a state in which insulin-interacting cells exhibit decreased sensitivity to insulin. Increase in insulin resistance is known to cause type II diabetes and have close relation to the onset of hypertension and progress of arteriosclerosis.
[0005] Thiazolidines are typical agents which are effective in overcoming insulin resistance. It has been known that when such thiazolidines typified by rosiglitazone or pioglitazone are attached to PPARγ, which is a nuclear receptor, PPARγ is activated, whereby adipose cells are differentiated (J. Biol. Chem. 270, 12953 to 12956 (1995)). However, thiazolidine-based drugs exhibit adverse side effects such as toxicity to the liver, edema, and increase in body weight. Thus, in the treatment of diabetes, a thiazolidine-based drug has been used as an auxiliary medicine to be administered along with a sulfonylurea drug.
[0006] In general, diabetes patients often suffer from other diseases. Therefore, reducing or ameliorating insulin resistance is important not only in the treatment of diabetes but also for other pathological conditions. For example, patients of hyperlipemia often exhibit hyperglycemia in relation to insulin resistance. Such patients must be treated for overcoming anomalous lipid metabolism and reducing insulin resistance. As has already been described in literature, α-glycosidase, serving as an oral hypoglycemic agent, remarkably reduces the risk of the onset of heart infarction by virtue of the insulin resistance reduction effect thereof (Lancet, (2002), 359:2072), suggesting that a combined treatment targeting anomalous lipid metabolism and high insulin resistance would be promising treatment. As mentioned above, since thiazolidine-based drugs exhibit adverse side effects such as toxicity to the liver and increase in body weight, other insulin resistance reducing agents that are safer and more effective are demanded in the therapy of hyperlipemia.
[0007] Meanwhile, Pitavastatin (i.e., 3-hydroxy-3-methylglutalyl-CoA (HMG-CoA) reductase inhibitor), which is a first choice drug for hyperlipemia (disclosed in JP-B-2569746, U.S. Pat. No. 5,856,336, and EP Patent No. 304063), is known to exhibit an effective blood cholesterol reducing effect in basic research and in clinical settings, as reported in Cardiovasc. Drug Rev. (2003) 21(3), 199 to 215. Meanwhile, pitavastatin exhibits an effect of improving impaired glucose tolerance (insulin resistance reducing effect) in KKAy mice, which are type II diabetes model mice (Therapeutic Research (0289-8020) vol. 24, No. 7, p. 1329-1337 (2003.07)). WO2004/09276 discloses that pravastatin, which is an HMG-CoA reductase inhibitor, also exhibits an effect of reversing impaired glucose tolerance in KKAy mice. However, improvement of the above-obtained effects in overcoming impaired glucose tolerance is still required.
[0008] As described above, for the hyperlipemia patients suffering hyperlipemia concomitant with insulin-resistance-related hyperglycemia, in addition to anomalous lipid metabolism, insulin resistance must be properly controlled. However, hitherto, a useful method for the composite treatment of anomalous lipid metabolism and high insulin resistance has never been known.
[0009] An object of the present invention is to provide method for treating diabetes having reduced side effect which exhibits excellent ameliorating effect for insulin resistance.
SUMMRY OF THE INVENTION
[0010] In view of the foregoing, the present inventors have conducted extensive studies, and have found that, among HMG-CoA reductase inhibitors, combined use of pravastatin and enalapril maleate serving as an ACE inhibitor only exhibits an effect of improving impaired glucose tolerance almost equivalent to that obtained when each drug component is administered singly; however, when pitavastatin and enalapril maleate are used in combination, the effect of improving impaired glucose tolerance is remarkably enhanced, and the combined use is beneficial for improving anomalous lipid metabolism and reducing insulin resistance as well. The present invention has been accomplished on the basis of these findings.
[0011] Some angiotensin converting enzyme (ACE) inhibitors, serving as hypertension treatment drugs, are known to exhibit an insulin resistance reducing effect. For example, JRAAS (2003), 4(2), 119 to 123 discloses a hypotensive effect and an insulin resistance reducing effect provided by enalapril maleate, and Hypertension, 2002; 40:329 discloses reduction of insulin resistance of KKAy mice in the glucose tolerance test employing temocapril. However, hitherto, there has never been reported combined use of an HMG-CoA reductase inhibitor and an ACE inhibitor as a new method for improving anomalous lipid metabolism and impaired glucose tolerance. In addition, the combined effect on impaired glucose tolerance (diabetes) obtained through use of these two drug components in combination has never been conceived by those skilled in the art. More specifically, the combined effect on impaired glucose tolerance obtained through use of pitavastatin and enalapril maleate in combination has never been known to those skilled in the art.
[0012] Accordingly, the present invention provides a method for treatment of diabetes, comprising administering a pitavastatin, and in combination therewith, enalapril or a salt thereof.
[0013] An excellent improving effect on impaired glucose tolerance (i.e., improving effect on insulin resistance) is obtainable by the treatment method of the present invention, and it is useful for treatment of diabetes, especially type II diabetes. Moreover, a combinational therapy targeting anomalous lipid metabolism and impaired glucose tolerance of a patient of hyperlipemia who is simultaneously suffered from hyperglycemia due to insulin resistance becomes possible
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a graph showing an AUC (area under the curve) of blood glucose level when pitavastatin calcium (represented by pitavastatin) and enalapril maleate were administered in combination; and
[0015] FIG. 2 is a graph showing an AUC of blood glucose level when pravastatin sodium (represented by pravastatin) and enalapril maleate were administered in combination.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0016] As used herein, the word “pitavastatin” collectively refers to pitavastatin per se, a salt thereof, and a lactone-formed species thereof. Hydrates and solvates formed with a pharmaceutically acceptable solvent also fall within the scope of pitavastatin. Pitavastatin exhibits a cholesterol synthesis inhibitory activity on the basis of an HMG-CoA reductase inhibitor and is known as a hyperlipemia treatment drug. Examples of the salts of pitavastatin include alkali metal salts such as sodium salts and potassium salts; alkaline earth metal salts such as calcium salts and magnesium salts; organic amine salts such as phenetylamine salts; and ammonium salts. Among the above pitavastatin species, pitavastatin salts are preferred, with calcium salts and sodium salts being particularly preferred.
[0017] Pitavastatin and related species thereof may be produced through a method disclosed in U.S. Pat. No. 5,856,336 or JP-A-1989-279866.
[0018] Enalapril, employed in the present invention, is an ACE inhibitor and readily available as a commercial product. No particular limitation is imposed on the salt of enalapril so long as the salt is pharmacologically acceptable. Examples of the salt include inorganic acid salts such as hydrochloride, sulfate, nitrate, hydrobromide, and phosphate, and organic acid salts such as acetate, trifluoroacetate, fumalate, maleate, lactate, tartrate, citrate, succinate, malonate, methanesulfonate, and p-toluenesulfonate. Of these, maleate is preferred.
[0019] According to the present invention, a pitavastatin, and enalapril or a salt thereof are administered in combination. As shown in the Example hereinbelow, combined administration has yielded a remarkable improvement in the impaired glucose tolerance in KKAy mice, as compared with sole administration of a pitavastatin or sole administration of enalapril or a salt thereof.
[0020] A KKAy mouse is a model for type II diabetes. Thus, the effect of a drug on improvement of impaired glucose tolerance (reduction of insulin resistance) can be evaluated on the basis of the degree of improvement of impaired glucose tolerance of KKAy mice. Therefore, the method of the present invention is useful for the treatment of a disease characterized by impaired glucose tolerance, particularly for the treatment of type II diabetes.
[0021] In the present invention, the formulation of a pitavastatin, and enalapril or a salt thereof may be appropriately selected in consideration of the condition of a patient or other factors. For example, the formulation may be any of powder, granules, dry syrup, tablets, capsules, and injections. These formulations may be produced through any production method known in the art by admixing a pharmaceutically acceptable carrier with a pitavastatin, and enalapril or a salt thereof.
[0022] In manufacture of oral solid preparations, the two drug components are admixed with a vehicle and, in accordance with needs, additives such as a binder, a disintegrant, a lubricant, a colorant, a flavoring agent, and an aroma. Various formulations such as tablets, granules, powder, and capsules may be produced from the mixture through a routine method. Additives generally employed in the art may be used as the above additives. Examples of the vehicle include lactose, sodium chloride, glucose, starch, microcrystalline cellulose, and silicic acid. Examples of the binder include water, ethanol, propanol, simple syrup, liquid gelatin, hydroxypropyl cellulose, methyl cellulose, ethyl cellulose, Shellac, calcium phosphate, and poly(vinylpyrrolidone). Examples of the disintegrant include agar powder, sodium hydrogencarbonate, sodium lauryl sulfate, and stearic monoglyceride. Examples of the lubricant include refined talc, stearate salts, borax, and polyethylene glycol. Examples of the colorant include β-carotene, yellow iron sesquioxide, and caramel. Examples of the flavoring agent include white sugar and bitter orange peel.
[0023] In manufacture of oral liquid preparations, the two drug components are admixed with additives such as a flavoring agent, a buffer, a stabilizer, and a preservative. Various formulations such as oral liquids, syrups, and elixirs may be produced from the mixture through a routine method. Additives generally employed in the art may be used as the above additives. Examples of the flavoring agent include white sugar. Examples of the buffer include sodium citrate. Examples of the stabilizer include traganth. Examples of the preservative include paraoxybenzoate esters.
[0024] In manufacture of injections, the two drug components are admixed with additives such as a pH-regulator, a stabilizer, and a tonicity agent. Various formulations such as subcutaneous injections, intramuscular injections, and intravenous injections may be produced from the mixture through a routine method. Additives generally employed in the art may be used as the above additives. Examples of the pH-regulator include sodium phosphate. Examples of the stabilizer include sodium pyrosulfite. Examples of the tonicity agent include sodium chloride.
[0025] In the treatment method according to the present invention, no particular limitation is imposed on the administration mode of a pitavastatin and enalapril (or a enalapril salt). Specifically, two drug components may be administered simultaneously or separately with an interval. In other words, a pitavastatin and enalapril (or an enelapril salt) may be formulated as a single preparation. Alternatively, two components may be separately formulated to provide corresponding preparations for producing a kit. In the latter case, two preparations may have different physical shapes. Frequency of administration of a pitavastatin may differ from that of enalapril or a salt thereof.
[0026] According to the present invention, when two components are contained in a single preparation, and such a preparation is administered to a patient in need thereof, a pitavastatin and enalapril (or an enalapril salt) are preferably formulated at a ratio by mass of 1:0.05 to 1:50, more preferably 1:0.1 to 1:10.
[0027] In the present invention, the dose of each drug component is suitably selected in consideration of the symptoms. The dose of pitavastatin is 0.1 to 50 mg per day, preferably 1 to 20 mg per day. The dose of enalapril or a salt thereof is 1 to 50 mg per day, preferably 2.5 to 20 mg per day. Two components may be administered once a day or two or more times a day in a divided manner.
EXAMPLES
[0028] The present invention will next be described in detail by way of examples, which should not be construed as limiting the invention thereto.
Example 1
[0029] Effects of combined administration of pitavastatin calcium (hereinafter referred to simply as pitavastatin) and enalapril maleate on impaired glucose tolerance were evaluated through the following test procedure.
1. Tested Animal and Breeding Environment
[0030] Male KKAy mice (age: 10 weeks, Nippon Cler Co., Ltd.) were provided. Throughout the duration of the experiment, the mice were housed in a cage with a controlled light/dark cycle (duration of light period with a room light: 7:00 a.m. to 7:00 p.m.) at a temperature of 23±3° C. and a humidity of 55±15% and were allowed to freely take a solid chow (CE-2; Nippon Cler Co., Ltd.) and tap water.
2. Drug Preparation
[0031] Pitavastatin and/or enalapril maleate were suspended in a 0.5-mass % aqueous solution of carboxymethyl cellulose (Iwai Kagaku Co., Ltd.) so that the pitavastatin content and the enalapril maleate content were adjusted to 1 mg/mL and 0.1 mg/mL, respectively. Since pitavastatin has a water content of 9.43%, pitavastatin was weighed in an amount of 1.1 times by mass the target dose for compensation. The suspension was refrigerated (4° C.) in a light-tight bottle. The suspensions were prepared every 7 days.
3. Test Method
[0032] Twenty four KKAy mice were randomly divided into the following four groups (six mice per group): a control group, a pitavastatin alone (10 mg/kg) group, an enalapril maleate alone (1 mg/kg) group, and a pitavastatin (10 mg/kg) and enalapril maleate (1 mg/kg) combined use group. Each of pitavastatin and enalapril maleate was orally administered once a day at a dose of 10 mL/kg for 21 days, and a 0.5 mass % aqueous sodium carboxymethyl cellulose solution (10 mL/kg) was orally administered to the control group. In all groups, the oral glucose tolerance test was performed after fasting for 18 hours following the final administration. Specifically, the tail of each mouse was cut (about 3 mm from the tip), thereby collecting blood from the tail vein. Immediately after collection, blood glucose level was determined by means of a medisafe reader (GR-101, product of Terumo Co., Ltd.). After determination of the initial blood glucose level, an aqueous glucose solution was orally administered to each mouse (2 g/10 mL/kg), and blood glucose level was determined in a similar manner at 15, 30, 60, and 120 minutes after administration of glucose. In each group, AUC of blood glucose level was calculated.
4. Statistical Analysis and Data Processing Method
[0033] The differences between the control group and the drug-administered groups were analyzed on the basis of Dunnett's multiple comparison test, preceded by Bartlett's analysis of variance. Significance levels less than 5% were considered to indicate statistically significant results.
5. Results
[0034] FIG. 1 shows an AUC of blood glucose level (to glucose tolerance hour 2). The AUC of blood glucose level represents the total amount of blood glucose. Therefore, a decrease in AUC is considered to indicate improvement of impaired glucose tolerance.
Comparative Example 1
[0035] The evaluation procedure of Example 1 was repeated, except that pravastatin sodium (hereinafter referred to simply as pravastatin) (50 mg/kg) was used instead of pitavastatin. Pravastatin (50 mg/kg) has a blood cholesterol level reducing effect almost equivalent to that of pitavastatin (10 mg/kg).
1. Drug Preparation
[0036] The procedure of Example 1 was repeated, except that the pravastatin content was adjusted to 5 mg/mL, whereby a drug was prepared.
2. Test Method
[0037] Testing was performed in a manner similar to that of Example 1. However, twenty four KKAy mice were randomly divided into the following four groups (six mice per group): a control group, a pravastatin alone (50 mg/kg) group, an enalapril maleate alone (1 mg/kg) group, and a pravastatin (50 mg/kg) and enalapril maleate (1 mg/kg) combined use group.
3. Statistical Analysis and Data Processing Method
[0038] Statistical Analysis and Data Processing are performed in a manner similar to that of Example 1.
4. Results
[0039] FIG. 2 shows an AUC of blood glucose level (to glucose tolerance hour 2).
[0040] The test results are summarized as follows.
[0041] AUC of blood glucose level tended to be reduced in the pitavastatin alone group, the pravastatin alone group, and the enalapril maleate alone group, as compared with the control group. The pravastatin and enalapril maleate combined administration group exhibited no combination effect, and the AUC tended to be reduced. In contrast, the pitavastatin and enalapril maleate combined administration group exhibited a considerable decrease in AUC as compared with the single administration groups. That is, impaired glucose tolerance was considerably improved (P<0.05), and the effect was found to be synergistic (relative index of the pitavastatin-enalapril maleate combined administration group (0.67)<product of relative index of the pitavastatin alone group and that of the enalapril maleate alone group (0.82)).
[0042] Accordingly, administration of pitavastatin and enalapril maleate in combination according to the present invention was found to exhibit a remarkable effect of improving impaired glucose tolerance, as compared with administration of another HMG-CoA reductase inhibitor and enalapril maleate in combination. | The present invention provides a method for treatment of diabetes, comprising administering a pitavastatin, and in combination therewith, enalapril or a salt thereof. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent Application No. 60/532,501 filed on Dec. 24, 2003.
TECHNICAL FIELD
[0002] This invention relates to the field of mounting structures for phallic devices such as penis substitutes, elongate sexual devices, dildos, vibrators, and the like.
BACKGROUND OF THE INVENTION
[0003] Phallic devices have been used for many years primarily for sexual pleasure both by couples and by people who do not have a sex partner. The phallic device is an elongate object sized and shaped to be inserted into the vagina of a woman and/or the anus of a person. Usually, phallic devices are either a smooth edged contoured cylinder or they are shaped to resemble either an erect or flaccid human penis. More recently, modern fabrication methods and materials allow phallic devices to be formed into any shape, size, or texture.
[0004] The use of phallic devices for obtaining sexual pleasure is gaining popularity along with social acceptance. This increased popularity is due to a number of social and environmental factors including: 1) an increase in sexually transmitted diseases such as AIDS and the like; 2) an increasingly open attitude towards human sexuality within our society; and 3) a desire for couples and people who do not have a sex partner to privately and safely explore a wide variety of sexual experiences.
[0005] Despite increasing social acceptance of phallic devices, most users prefer to keep them, and any related structures associated with using them, concealed when not in use.
[0006] Historically, most phallic devices are held by the user themselves or by a sexual partner during use. Unfortunately, the number of sexual activities that may be simulated or performed by a user is necessarily limited by the phallic device holders' reach and the holder's range of movement available. Moreover, physically challenged individuals may not have the capacity to properly hold the phallic device for use. Accordingly, their ability to enjoy the benefits of these devices is limited.
[0007] Recently, efforts have been made to provide hands-free use of phallic devices.
[0008] For example, U.S. Pat. No. 5,690,604 to Barnett (“Barnett”) discloses mounting a phallic device to a C-shaped clamp. The C-shaped clamp may then be secured by a user to a support structure, such as a bedpost or the like. Similarly, U.S. Pat. No. 5,127,396 to McAllister (“McAllister”) discloses mounting a phallic device to a universal mount. The universal mount may then be strapped around a wearer's torso, thereby allowing the wearer to insert the phallic device into their partner and simulate thrusting movements normally associated with performing the sexual act.
[0009] Despite the benefits offered by these types of phallic device mounting structures, they have several drawbacks. For example, a hand-tightened clamp on a bed frame is often insufficient to withstand the forces generated during use of the phallic device.
[0010] Accordingly, the phallic device may tend to move or detach from the bed frame during use. Such movement can damage the bed frame, or worse yet; injure a user.
[0011] Moreover, the mounting structure in Barnett requires a user to have a suitably sized support structure for engaging the C-shaped clamp positioned at substantially the same height where the phallic device must be positioned for use. In practice, this positioning for the support structure is difficult to find in a suitably private environment sufficient for using the phallic device therein.
[0012] Similarly, while the strap on mounting structure in McAllister may offer sexual partners an opportunity to engage in a new sexual experience together, it does not allow hands free use of the phallic device by a single user. Also, both the C-shaped clamp in Barnett and the strap on mounting structure in McAllister are not particularly aesthetically pleasing, nor do they allow for easy concealment and storage when not in use.
SUMMARY OF THE INVENTION
[0013] Accordingly, despite the available phallic device mounting structures, there remains a need for an adjustable phallic device mount that provides hands-free use of the phallic device, that is easy to assemble, adjust and use, and provides rigid support for the phallic device during use, and that may be easily concealed and stored when not in use. In addition to other benefits that will become apparent in the following disclosure, the present invention fulfills these needs.
[0014] The invention is a phallic device mount for operably securing a phallic device thereto. The mount is positioned adjacent to and supported by a bed. A substantially planar bed-engaging portion is positioned below the mattress of the bed and extends to the mount thereby supporting the mount during use. Preferably, the substantially planar bed-engaging portion is retractable within the mount for easy concealment when not in use. In a preferred embodiment, the height of the planar bed-engaging portion and the height of the phallic device are both independently adjustable by a user.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is an isometric, front view of a phallic device mount in accordance with an embodiment of the present invention showing a possible in-use position and a possible orientation with respect to a bed.
[0016] FIG. 2 is an isometric, back view of the phallic device mount structure of FIG. 1 showing a possible retracted position.
[0017] FIG. 3 is an exploded, isometric view of the phallic device mount of FIG. 1 .
[0018] FIG. 4 is a cross sectional view of the phallic device mount of FIG. 1 taken along line 4 - 4 of FIG. 1 .
[0019] FIG. 5 is an isometric, front view of a phallic device mount in accordance with an alternative embodiment of the present invention showing a possible in-use position and a possible orientation with respect to a bed.
[0020] FIG. 6 is an isometric, back view of the phallic device mount structure of FIG. 5 showing possible movement of a bed-mounting portion.
[0021] FIG. 7 is a cross sectional view of the phallic device mount of FIG. 5 taken along line 7 - 7 of FIG. 6 .
[0022] FIG. 8 is an isometric view of a phallic device mounting portion of an embodiment of the present invention used in a possible alternative mounting to an auxiliary support structure in accordance with an embodiment of the present invention.
[0023] FIG. 9 is a section view of the phallic device mounting portion of FIG. 8 taken along line 9 - 9 of FIG. 8 .
DETAILED DESCRIPTION
[0024] A mount 20 for a phallic device 22 is shown in FIGS. 1-7 . The mount 20 preferably includes a height adjustable phallic device mounting portion 24 and a height adjustable bed-mounting portion 26 .
[0000] A. General Assembly
[0025] Referring to FIGS. 1 and 3 , the mount 20 preferably includes a substantially planar base 28 defining a front side 30 , back side 32 , left side 34 , right side 36 , upper edge 38 , lower edge 40 , and left and right edges 42 , 44 , respectively. Feet 46 , preferably having anti-slip material 48 such as rubber or the like on their lower sides 50 , are secured to the lower edge 40 of the substantially planar base 28 .
[0026] The phallic device mounting portion 24 includes a structure 52 for mounting a phallic device 22 such as a penis substitute, elongate sexual device, dildos, vibrators, or the like, thereto. Preferably, the phallic device mounting portion 24 includes a substantially planar front surface 54 with the phallic device 22 extending substantially perpendicular thereto. More preferably, the phallic device mounting portion 24 is substantially planar and includes a face member 56 and a substantially planar base member 58 . The face member 56 is formed to define a recess 60 therein that is open along a top edge 62 . The recess 60 is preferably sized to detachably receive a substantially planar base portion 64 of the phallic device 22 . An opening 66 extending from the upper edge 38 of the face member 56 through the front surface 54 allows the phallic device 22 to extend therethrough.
[0027] Preferably, the phallic device 22 includes a universal mounting portion 22 ′ that is detachably secured to the phallic device mounting portion 24 , and a plurality of different phallic devices (not shown) each of which is adapted to be installed, one at a time, onto the universal mounting portion 22 ′. Such universal mounting portions 22 ′ are known. One such universal mounting portion is disclosed in U.S. Pat. No. 5,127,396 to McAllister, the disclosure of which is hereby incorporated by reference.
[0028] The phallic device mounting portion 24 is preferably slidably secured to the front side 30 of the base 28 . One possible sliding structure 70 includes positioning a left and right substantially planar member 72 , 74 , respectively, along the left and right sides 34 , 36 , respectively, of the substantially planar base 28 to define a substantially vertical channel 78 therebetween. The edges 80 , 82 of the substantially planar members 72 , 74 , respectively, directed toward the channel 78 each include a lip 84 , or flange, extending toward the channel 78 . Mating recesses 86 , 88 extending along the left and right sides of the phallic device mounting portion 24 slidably engage the lips 84 on the left and right substantially planar members 72 , 74 thereby allowing the phallic device mounting portion 24 to slide substantially vertically in the direction of arrows 90 shown in FIG. 1 .
[0029] Preferably, the phallic device mounting portion 24 includes a locking system 92 for allowing a user to select a desired height of the phallic device 22 relative to the base 28 and secure the phallic device mounting portion 24 at that height. One known locking system 92 is best shown in FIG. 3 . The edges of the channel 78 include a plurality of vertically-aligned, spaced apart openings 94 . The phallic device mounting portion 24 includes substantially horizontal levers 96 , 98 slidably secured thereto with handle portions 100 , 102 , respectively, extending through parallel-aligned slots 104 , 106 in the face member 56 . Each lever 96 , 98 includes a protrusion 108 , 110 , respectively, extending therefrom for matingly engaging one of the plurality of openings 94 in the edges of the channel 78 . The levers 96 , 98 are preferably biased to an extended position wherein the protrusions 108 , 110 engage one of the openings 94 . Such biasing is preferably accomplished with a spring 112 extending between the levers 96 , 98 thereby urging them apart. More preferably, the spring 112 is operably secured to each lever 96 , 98 by pins 114 , 116 extending from each lever 96 , 98 toward the spring 112 as best shown in FIG. 4 .
[0030] A user adjusts the height of the phallic device mounting portion 24 by moving the handle portions 100 , 102 of each lever 96 , 98 towards each other, thereby disengaging the protrusions 108 , 110 from their mating openings 94 . The user slides the phallic device mounting portion 24 along the channel 78 to the desired height and then releases the handle portion 100 , 102 . The spring 112 urges the levers 96 , 98 to extend the protrusions 108 , 110 toward the edge of the channel 78 . Accordingly, the protrusions 108 , 110 are operably received within the adjacent openings 94 thereby securing the phallic device mounting portion 24 at the selected height.
[0031] The height adjustable bed mounting portion 26 preferably includes a substantially planar bed engaging portion 120 that is operably secured to a base engaging portion 122 . Preferably, the base engaging portion 122 is slidably secured to the back side 32 of the base 28 . More preferably, the bed engaging portion 120 is pivotally secured at a first end 124 to the base engaging portion 122 such that the bed mounting portion 26 moves with respect to the base 28 in the direction of arrows 126 ( FIG. 1 ) to define a retracted position 130 ( FIG. 2 ) in which the bed engaging portion 120 is positioned substantially parallel to and substantially adjacent to the base 28 , and an in-use position 132 ( FIG. 1 ) in which the bed engaging portion 120 is positioned substantially perpendicular to the base 28 as best shown in FIG. 1 .
[0032] Even more preferably, the bed engaging portion 120 is pivotally secured to the base 28 with an elongate hinge 138 , and anti-slip material 140 , such as rubber or the like is positioned on the bed engaging portion 120 toward the opposite second end 142 of the bed engaging portion 120 . In order to reduce the overall weight of the phallic device mount 20 , the bed engaging portion 120 may also include a large opening 144 therein as best shown in FIG. 3 .
[0033] One possible structure for slidably securing the base engaging portion 122 to the base 28 includes securing left and right rails 150 , 152 , respectively, each having a lip 154 , or flange, extending therefrom to define a substantially vertical bed mounting portion channel 156 therebetween. Mating recesses 158 in the base engaging portion 122 operably engage the lips 154 thereby allowing the base engaging portion 122 to slide in the direction of arrows 160 ( FIG. 1 ).
[0034] Preferably, the base engaging portion 122 includes a locking system 162 for allowing a user to select a desired height of the bed mounting portion 26 relative to the base 28 and then secure the base engaging portion 122 at that height. One known locking system 162 is best shown in FIG. 3 . The rails 150 , 152 include a plurality of vertically-aligned, spaced apart openings 164 . The base engaging portion 122 includes substantially horizontal levers 166 , 168 slidably secured thereto with handle portions 170 , 172 extending through slots 174 , 176 in the face of the base engaging portion 122 . Each lever 166 , 168 includes a protrusion 178 , 180 extending therefrom for matingly engaging one of the plurality of openings 164 . The levers 166 , 168 are preferably biased to an extended position wherein the protrusions 178 , 180 engage one of the openings 164 . Such biasing is preferably accomplished with a spring 190 extending between the levers 166 , 168 thereby urging them apart. More preferably, the spring 190 is operably secured to each lever 166 , 168 by rods 192 , 194 extending from each lever 166 , 168 toward the spring 190 as best shown in FIG. 4 .
[0035] A user adjusts the height of the bed mounting portion 26 by moving the handle portions 170 , 172 of each lever 166 , 168 towards each other, thereby disengaging the protrusions from their mating openings. The user slides the base engaging portion 122 to the desired height and then released the handle portions 170 , 172 . The spring 190 urges the levers 166 , 168 to extend the protrusions 178 , 180 toward the openings 164 .
[0036] Accordingly, the protrusions 178 , 180 are operably received within the adjacent openings 164 thereby securing the bed mounting portion 26 at the selected height.
[0000] B. Use and Operation
[0037] A user uses the phallic device mount 20 by attaching a phallic device 22 to the phallic device mounting portion 24 and positioning the base 28 substantially vertically next to a bed 200 as shown in FIG. 1 . The user then adjusts the height of the bed mounting portion 26 so that the hinge 138 is substantially at the same height as a substantially horizontal surface 202 of the bed 200 , such as the break between the box springs 204 and mattress 206 . The user then moves the bed mounting portion 26 from its retracted position 130 ( FIG. 2 ) to its in use position 132 ( FIG. 1 ) and slides the bed engaging portion 120 between the box springs 204 and mattress 206 as shown thereby securing the base 28 to the bed 200 . The weight of the mattress 206 on the bed engaging portion 120 combined with the anti-slip material 140 on the bed engaging portion 120 further secure the base 28 in place. The user then adjusts the height of the phallic device 22 by adjusting the phallic device mounting portion 24 to the desired vertical height.
[0038] Preferably, the channel 78 is sized so as to allow the phallic device 22 to be positioned substantially anywhere along the vertical length of the base 28 including being substantially close to the lower edge 40 of the base 28 and the upper edge 38 of the base 28 . Accordingly, a user can use the phallic device 22 by either lying on their back on the floor adjacent to the phallic device mount 20 , in which case the phallic device mounting portion 24 is positioned toward the lower edge 40 of the base 28 , or by resting on all fours facing away from the phallic device mounting portion 24 such that their buttocks and/or vagina is aligned with the phallic device 22 .
[0000] C. Additional Features and Embodiments
[0039] In view of the wide variety of embodiments to which the principles of the invention can be applied, it should be apparent that the detailed embodiments are illustrative only and should not be taken as limiting the scope of the invention. For example, the embodiment disclosed in FIGS. 1-4 discloses the base 28 and bed mounting portion 26 to be substantially rectangular. This allows the bed mounting portion 26 to be received within the base 28 for easy storage and concealment of the mount 20 when not in use. FIGS. 5-7 disclose different shaped structures. In this alternative embodiment, the base 28 ′ is much narrower thereby allowing a user's legs to pass-by on either side easily during use. Also, the bed engaging portion 120 ′ includes a flared outer portion 220 , which preferably includes strips of anti-slip material 140 thereon, to thereby increase the surface area of the bed engaging portion 120 ′ and improve the rigidity and stability of the mount 20 ′ during use.
[0040] Also, as shown in FIGS. 8 & 9 , the phallic device mounting portion 24 may be completely detached from the base 28 and used as a stand-alone phallic device mount. For example, a strap 260 can be secured to the phallic device 22 and wrapped around an auxiliary support structure 262 , such as a door or the like, to allow a user additional opportunities to use their phallic device 22 . In such case, the phallic device mount 20 can include one or more slots 264 for allowing the strap 260 to be passed therethrough. The strap 260 preferably includes securing structures such as a buckle or hook and loop material 266 , thereby allowing a user to detachably secure just the phallic device mounting portion 24 to an auxiliary support structure 262 .
[0041] In addition, the phallic device mount 20 of the present invention may be used in other ways as well. For example, the base 28 may be positioned substantially horizontally extending between the seats of two chairs or the like or resting flat on a substantially horizontal surface such as a bed. In such case, the bed mounting portion 26 preferably remains in its retracted position 130 ( FIG. 2 ).
[0042] In can appreciated that the mount 28 can also be used to assist paraplegics, quadriplegics, and others with conditions that limit their movement, to simulate normal sexual intercourse with a partner. The adjustability of the mount 28 allows the phallic device mounting portion to be laid over, on, under or attached to a wheelchair, hospital bed or other assistive device thereby allowing such individuals to engage in a large variety of sexual experiences. In addition, the mount 28 may stand alone to allow and individual with a disfiguring condition to simulate the experience of sexual intercourse without a partner.
[0043] In light of these additional embodiments and methods of use, the claimed invention includes all such modifications as may come within the scope of the following claims and equivalents thereto. | A phallic device mount for operably securing a phallic device thereto and a method of use are disclosed. The mount is positioned adjacent to and supported by a bed. A substantially planar bed-engaging portion is positioned below the mattress of the bed and extends to the mount thereby holding the mount in place during use. Preferably, the substantially planar bed-engaging portion is retractable within the mount for easy concealment of the mount when not in use, and it is slideably secured between a box spring and mattress of the bed during use of the mount. In a preferred embodiment, the height of the planar bed-engaging portion and the height of the phallic device are both independently adjustable by a user. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an improved process for the preparation of polyester polyols. More particularly, the invention relates to an improved multistep batch process for the prepartion of polyester polyols by the reaction of a polycarboxylic acid or anhydride with a polyhydric alcohol.
2. Prior Art
The preparation of polyester polyols by the reaction of a polycarboxylic acid or anhydride with a polyhydric alcohol is well known in the art as evidenced by U.S. Pats. Nos. 3,162,616 and 3,716,523. Generally, the processes of the prior art involve a one-step reaction of a polycarboxylic acid or anhydride with a stoichiometric excess amount of a polyhydric alcohol. An excess amount of alcohol is employed to assure that both ends of the polyester terminate in hydroxyl groups, thus providing polyester polyols of low acid numbers, that is, two or less.
One of the problems associated with the prior art processes of preparing polyester polyols from polycarboxylic acids or anhydrides and polyhydric alcohols is the water formed during the esterification, which must be removed from the reaction site. Since for each mole of polycarboxylic acid or anhydride employed in the preparation of the polyol there is produced from 1 to 2 moles of water, the water occupies valuable reactor space, limiting the amounts of reactants which may be initially charged to the reactor. In the normal accepted procedures for the preparation of polyester polyols, all the reactants are charged to a reactor and as the reaction proceeds the water of esterification is removed from the reactor by distillation. Depending on the polyol and the acid or anhydride employed, the amount of water which is removed is approximately 20 to 30% by weight of the total charge. Thus, the final yield of polyol is generally 20 to 30% less than the weight of the charge. The present invention is directed to an improvement in the above-described prior art processes of preparing polyester polyols which allows for an increase in reactor capacity without equipment modification at the same cycle times.
SUMMARY OF THE INVENTION
The present invention relates to an improved process for the preparation of polyester polyols by the esterification of a polycarboxylic acid or anhydride with a polyhydric alcohol which involves initially heating a stoichiometric excess amount of a polycarboxylic acid or anhydride with a polyhydric alcohol, removing between 90 to 95% by weight of the water of esterification, adjusting the stoichiometry of the reaction by addition of polyhydric alcohol, and continuing the esterification reaction until a polyol having a desired acid number and hydroxyl number is obtained.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention relates to a process for the preparation of a polyol by the esterification of a polycarboxylic acid or anhydride with a polyhydric alcohol which comprises:
a. initially charging to a reactor an amount of a polycarboxylic acid or anhydride equal to between 3 to 16, preferably 6 to 12, weight percent in excess of stoichiometry;
b. adding to the reactor a polyhydric alcohol and heating the charge to a temperature between 130° to 240° C.;
c. removing from the reactor between 90 to 95 weight percent of the water of esterification resulting from step (b);
d. charging to the reactor an amount of polyhydric alcohol substantially equivalent in weight to the amount of water of esterification removed from step (c); and
e. continuing the esterification reaction until a polyol having an acid number of less than two is obtained.
There are two essential reactants employed in the process of the subject invention, namely, a polycarboxylic acid or anhydride and a polyhydric alcohol. Representative polycarboxylic acids and anhydrides which may be employed include oxalic, malonic, succinic, glutaric, adipic, pimelic, suberic, azelaic, sebacic, brassylic, thapsic, maleic, fumaric, glutaconic, α-hydromuconic, β-hydromuconic, α-butyl-α-ethyl-glutaric, α-β-diethylsuccinic, isophthalic, terephthalic, hemimellitic, and 1,4-cyclohexanedicarboxylic. Any suitable polyhydric alcohol including both aliphatic and aromatic may be used such as ethylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol, trimethylene glycol, 1,2-propylene glycol, 1,4-tetramethylene glycol, 1,2-butylene glycol, 1,4-butane diol, 1,3-butane diol, 1,5-pentane diol, 1,4-pentane diol, 1,3-pentane diol, 1,6-hexane diol, 1,7-heptane diol, glycerol, 1,1,1-trimethylolpropane, 1,1,1-trimethylolethane, hexane-1,2,6-triol, neopentylglycol, dibromoneopentylglycol, 1,10-decanediol, and 2,2-bis(4-hydroxycyclohexyl)propane.
The esterification reaction of the present invention is generally carried out in the presence of an inert atmosphere such as nitrogen or carbon dioxide. Generally the acid and/or anhydride component and a portion of the polyhydric alcohol are charged to a reactor and with stirring the charge is heated to a temperature between 130° and 240° C. Heating is continued such that the water of esterification can be rapidly removed, generally by distillation. Upon removing between 90 to 95 weight percent of the theoretical water of esterification from the reactor, an additional amount of polyhydric alcohol is charged to the reactor and esterification is continued until the acid number of the polyol is less than two and all of the water of esterification is removed.
Although the reaction proceeds promptly with heating and no catalyst is required, if desired a catalyst may be employed during the reaction, preferably being charged along with or shortly after the second polyhydric alcohol charge. Representative esterification catalysts include organic metal compounds such as those described in U.S. Pat. Nos. 3,162,616 and 3,716,523.
The total time for the esterification reaction may vary from 6 hours to 48 hours, preferably from 12 hours to 24 hours. The time will depend on the reactivity of the reactants, the stoichiometry, temperature, and pressure employed in the reaction, the molecular weight of the resulting polyester polyols, the rapidity with which the water of esterification is removed, and the activity of the catalyst employed, if any.
The polyester polyols prepared in the subject invention are particularly useful in the preparation of polyurethane compositions such as textile coatings (tie coatings and top coatings), elastomers, shoe sole composites, flexible, rigid and microcellular foams, as well as urethane rubbers, sealants, and adhesives.
The following examples illustrate the invention. All parts are by weight unless otherwise indicated.
EXAMPLE I
A reaction vessel equipped with a condenser, agitator, thermometer, column, nitrogen source and inlet and outlet tubes was charged with 1,000 parts (6.84 moles) of adipic acid and 606 parts (5.71 moles) of diethylene glycol. The above charges represent a 11.9 weight percent stoichiometric excess of adipic acid. The vessel was sealed and vacuum purged. The vacuum was then released with nitrogen and the charge was heated to about 140° C. at which temperature water began to distill out of the reactor. Heating continued until the temperature of the charge reached 200° C. during which time water was continually distilled. When approximately 95% by weight (193 parts) of the theoretical amount of water had been removed, 190.4 parts (1.79 moles) of diethylene glycol was charged to the reactor. The total glycol charge was 1% in excess of the stoichiometric amount calculated to yield a polyester diol having a molecular weight of 2440. Heating was continued at a charge temperature of about 225° C. and a pressure of 10 mm. of mercury and water was removed intermittently during this period.
When the acid number of the product reached sixteen, 0.10 part of a tetraalkyltitanate-stannous alcoholate esterification catalyst was added to the reactor and heating continued and water removed until an acid number of less than one was reached. The reactants were then cooled to 100° C. and discharged therefrom. Total cycle or reaction time was 14 hours. The resulting polyester polyol (1467 parts) had a hydroxyl number of 46 and an acid number of 0.6.
The above run was repeated except that 892 parts of adipic acid and 714 parts of diethylene glycol are all charged to the reactor, filling the reactor to capacity. The reaction was then carried out under essentially the same conditions of pressure, temperature, and time. A yield of 1311 parts of polyester polyol having a hydroxyl number of 46 and an acid number of 0.6 was obtained. The amount of polyol represents a 11.9% decrease in yield over the process of the subject invention.
EXAMPLE II
Following the procedure described in Example I with the exception that an esterification catalyst was not employed, a 2000 molecular weight polyester polyol was prepared from adipic acid, ethylene glycol, and 1,4-butane diol. The amounts of reactants employed were as follows:
______________________________________Initial Charge: Parts Moles______________________________________ Adipic Acid 1143 7.82 Ethylene Glycol 271 4.37 1,4-Butane Diol 191 2.12Second Charge: Parts Moles______________________________________ 1,4-Butane Diol 195 2.16______________________________________
The initial charge represented a 12.2 weight percent excess of adipic acid. The second charge was added after 219 parts of water (95% of theory) had been removed from the reactor. The total glycol charged was 1% in excess of the stoichiometric amount calculated to yield a polyester diol having a molecular weight of 2000. The temperature of the reaction varied from 180° to 225° C. and the pressure was 10 mm. of mercury. The cycle time was 16 hours. The resulting polyester polyol (1437 parts) had a hydroxyl number of 56 and an acid number of 0.5.
The above run was repeated except that 1018 parts of adipic acid, 243 parts of ethylene glycol and 344 parts of 1,4-butane diol are all charged to the reactor at once, filling the reactor to capacity. The total glycol charged was 1% in excess of the stoichiometric amount calculated to yield a polyester diol having a molecular weight of 2000. The reaction was then carried out under essentially the same conditions of pressure, temperature, and time. A yield of 1281 parts of polyester polyol having a hydroxyl number of 56 and an acid number of 0.5 was obtained. The amount of polyol represents a 12.2% decrease in yield over the process of the subject invention.
EXAMPLE III
Following the procedure described in Example I with the exception that an esterification catalyst was not employed, a 1000 molecular weight polyester polyol was prepared from adipic acid and ethylene glycol. The amounts of reactants employed were as follows:
______________________________________Initial Charge: Parts Moles______________________________________ Adipic Acid 1122 7.68 Ethylene Glycol 384 6.19Second Charge: Ethylene Glycol 186 3.00______________________________________
The initial charge represented a 12.5 weight percent excess of adipic acid. The second charge was added after 208 parts of water (95% of theory) had been removed from the reactor. The total glycol charged was 1% in excess of the stoichiometric amount calculated to yield a polyester diol having a molecular weight of 1000. The temperature of the reaction varied from 180° to 235° C. and the pressure was 10 mm. of mercury. The cycle time was 17 hours. The resulting polyester polyol (1340 parts) had a hydroxyl number of 112 and acid number of 0.06.
The above run was repeated except that 998 parts of adipic acid and 508 parts of ethylene glycol are all charged to the reactor at once, filling the reactor to capacity. The total glycol charged was 1% in excess of the stoichiometric amount calculated to yield a polyester diol having a molecular weight of 1000. The reaction was then carried out under essentially the same conditions of pressure, temperature and time. A yield of 1191 parts of polyester polyol having a hydroxyl number of 112 and an acid number of 0.1 was obtained. The amount of polyol represents a 12.5% decrease in yield over the process of the subject invention.
EXAMPLE IV
Following the procedure described in Example I with the exception that an esterification catalyst was not employed, a 2000 molecular weight polyester polyol was prepared from adipic acid and ethylene glycol. The amounts of reactants employed were as follows:
______________________________________Initial Charge: Parts Moles______________________________________ Adipic Acid 1153 7.89 Ethylene Glycol 352 5.67Second Charge: Ethylene Glycol 187 3.01______________________________________
The initial charge represented a 12.5 weight percent excess of adipic acid. The second charge was added after 191 parts of water (95% of theory) had been removed from the reactor. The total glycol charge was 1% in excess of the stoichiometric amount calculated to yield a polyester diol having a molecular weight of 2000. The temperature of the reaction varied from 135° to 225° C. and the pressure was 10 mm. of mercury. The cycle time was 16.18 hours. The resulting polyester polyol (1333 parts) had a hydroxyl number of 56 and acid number of 0.5.
The above run was repeated except that 1026 parts of adipic acid and 480 parts of ethylene glycol are all charged to the reactor at once, filling the reactor to capacity. The total glycol charge was 1% in excess of the stoichiometric amount calculated to yield a polyester diol having a molecular weight of 2000. The reaction was then carried out under essentially the same conditions of pressure, temperature, and time. A yield of 1185 parts of polyester polyol having a hydroxyl number of 56 and an acid number of 0.5 was obtained. The amount of polyol represents a 12.5% decrease in yield over the process of the subject invention.
EXAMPLE V
Following the procedure described in Example I with the exception that the esterification catalyst employed was stannous octoate, a 476 molecular weight polyester polyol was prepared from phthalic anhydride, trimethylolpropane, and tetraethylene glycol. The amounts of reactants employed were as follows:
______________________________________Initial Charge: Parts Moles______________________________________ Tetraethylene Glycol 7045 36.3 Trimethylolpropane 4278 31.9 Phthalic Anhydride 5377 36.3Second Charge: Trimethylolpropane 592 4.4______________________________________
The initial charge represented a 3.6 weight percent excess of phthalic anhydride. The second charge was added after 620 parts of water (95% of theory) had been removed from the reactor. The temperature of the reaction varied from 170° to 210° C. The cycle time was 20 hours. The resulting polyester polyol (15,806 parts) had a hydroxyl number of 357 and acid number of 1.7.
The above run was repeated except that 6800 parts of tetraethylene glycol, 4700 parts of trimethylolpropane and 5190 parts of phthalic anhydride are all charged to the reactor at once, filling the reactor to capacity. The reaction was then carried out under essentially the same conditions of pressure, temperature and time. A yield of 15,257 parts of polyester polyol having a hydroxyl number of 356 and an acid number of 1.8 was obtained. The amount of polyol represents a 3.6% decrease in yield over the process of the subject invention. | Polyester polyols are prepared by the reaction of a polycarboxylic acid or anhydride with a polyhydric alcohol employing in an initial step a stoichiometric excess of polycarboxylic acid or anhydride, thereafter removing between 90 to 95% of the water of esterification, adjusting the stoichiometry of the reaction by addition of polyhydric alcohol, and continuing the esterification reaction until a polyester polyol having an acid number of less than two is obtained. The process allows for an increase in reactor capacity without equipment modification at the same cycle times and a decrease in side product formation. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This Application is a divisional of U.S. application Ser. No. 13/002,520 filed Feb. 10, 2011, which is a U.S. National Stage of International PCT Application No. PCT/PL2009/050010 filed Jul. 4, 2009, which claims benefit of the Poland Application No. PL385586 filed Jul. 4, 2008. All of these US and PCT applications are hereby incorporated herein by reference in their entirety.
SUMMARY
[0002] The subjects of the invention are new biosynthetic analogues of recombined human insulin of prolonged therapeutic activity, which may find use in prophylaxis and treatment of diabetes mellitus.
[0003] Insulin and its various derivatives are used in large amounts in treatments of diabetes mellitus and are often manufactured on a large industrial scale. While there are many different known modified derivatives of insulin and many pharmaceutical preparations of diverse activity profiles, a drug is still sought, which would enable to maintain a constant level of glucose in a human organism for an extended period of time.
[0004] To achieve the effect of delayed and/or prolonged activity some preparations of normal human insulin contain specific additions, e.g. various amounts of protamin, a protein that forms an insoluble complex with insulin which forms deposits in subcutaneous tissues, and from which insulin is gradually released.
[0005] There are known various human insulin derivatives used in treatment of diabetes, which contain additional amino acids or have modified sequence of some amino acids. Changes of primary structure of insulin influence its secondary and tertiary structure, which affects protein's chemical and biological properties, and that in turn results in pharmacokinetic and pharmacodynamic effects. These changes are of different character, can lead to accelerated or delayed and prolonged activity of modified insulin. Active form of insulin is a monomer, which easily filters into blood after subcutaneous injection. It is known, that exogenous human insulin in solutions has hexameric form, which after application dissociates to dimers and subsequently to monomers before filtering into blood stream. One of insulin derivatives characterised by accelerated activity is lispro-insulin (Humalog®), in which the sequence of proline (28)-lysine (29) in chain B has been inverted. It makes difficult, from the sterical point, to form dimers of insulin in a solution. Second such a derivative is insulin in which proline in the position 28 of chain B has been replaced with aspartic acid. Such introduced negative charge lowers possibility of self-association of insulin monomers. Both these insulin derivatives are absorbed faster due to their structure.
[0006] Prolonged-activity recombined human insulin analogues are constructed by elongating chain B with alkaline amino acids or acylating E-amino group in lysine in chain B with aliphatic acid of about a dozen carbon atoms.
[0007] Introduction of these extra alkaline amino acids changes some chemical or physical properties of insulin. The most important change is a shift of isoelectric point in respect to unmodified natural insulin from 5.4 to the range of about 5.5 to about 8.5, which results from introduction of superfluous positive charges into the molecule. In consequence solubility of these analogues in neutral water environment is reduced, and therefore necessity of using slightly acidic environment for production of pharmaceutical preparations containing such modified insulin.
[0008] However, beside obvious advantages resulting from introduction of extra alkaline amino acids there is observed also disadvantageous reduction of stability of new analogues, stemming primarily from deamination of asparagine in position A21 occurring in acidic environment.
[0009] This issue is addressed by replacement of A21Asn with other amino acid, such as aspartic acid, glycine, alanine, threonine and others. One of such analogues is recombinant human insulin derivative in which in chain A asparagine(21) has been replaced with glycine(21) and to the C terminus of chain B have been attached two arginine residues. This is so-called glargine derivative of insulin, manufactured under the name Lantus (patent U.S. Pat. No. 5,656,722).
[0010] In the course of our research it has been established, that a human insulin derivative, where to the C terminus of chain B have been attached residues of lysine (B31Lys) and arginine (B32Arg) shows biological activity that is similar to glargine derivative, which is already present on the market. Preliminary research performed on animals indicates, that this preparation, called lizarginsulin, is characterised by prolonged activity and a flat release profile mimicking secretion of natural insulin, and from a clinical point of view—reduction of nocturnal hypoglycaemias. Because of exceptional similarity to human insulin and also to proinsulin, there could be expected good research results, enabling gradual development of the drug candidate and its final commercialisation. It is crucial, that LysArg sequence at C terminus of chain B of human insulin is found in human proinsulin, and one should expect transformation of lizarginsulin into human insulin by present carboxypeptidase C. This means, that first metabolite of lizarginsulin in human organism can be human insulin of well known and acceptable characteristics, even in the case of exogenous hormone. There was performed extended pre-clinical research on rats, which confirmed prolonged activity of the new insulin analogue.
[0011] However it came out that this derivative apart of its advantageous biological activity is characterised by insufficient stability in acidic injection solutions. The main cause of insufficient stability, which manifests itself primarily as deamidation, is presence of asparagine residue at C terminus of chain A, where in acidic water environment can occur a deamidation autocatalysed by a proton from carboxyl group.
[0012] Therefore the aim of this invention is providing new analogues of insulin, which would be characterised by an adequate stability in acidic injection solutions (pH 3.5-5), and at the same time would possess the required biological activity. It is especially desirable that they would show characteristics of biological activity of natural insulin. It is also particularly important, that the start of activity of the new derivatives was practically immediate, just after administration to the patient, with the ability of prolonged release of a part of the dose. This would enable to provide both accelerated and prolonged activity of the pharmaceutical preparation containing insulin analogues.
[0013] The above stated goal was unexpectedly achieved in this invention.
[0014] The basic aspect of the invention is an insulin derivative or its pharmaceutically acceptable salt containing two polypeptides constituting chain A and chain B, where amino acid sequence of chain A has been chosen from SEQ ID No 1-5, while amino acid sequence of chain B has been chosen from SEQ ID No 6-8. Preferred insulin derivative or its pharmaceutically acceptable salt according to the invention is characterised by being an analogue of recombined human insulin of isoelectric point 5-8.5 and formula 1:
[0000]
[0000] where R denotes an NH 2 group or a group according to formula Asn-R 2 , where R 2 denotes a neutral L-amino acid or an NH 2 group; and R1 denotes B31Lys-B32Arg or B31Arg-B32Arg or B31Arg, where B3Asn may be alternatively replaced by other amino acid, advantageously by Glu.
Advantageously, the insulin derivative or its physiologically acceptable salt according to the invention is characterised by this, that: R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Gly and R 1 denotes B31 Lys-B32Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Ala and R 1 denotes B31 Lys-B32Arg or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Ser and R 1 denotes B31 Lys-B32Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Thr and R 1 denotes B31 Lys-B32Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes group NH 2 and R 1 denotes B31 Lys-B32Arg, or R in the formula 1 denotes group NH 2 and R 1 denotes B31 Lys-B32Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Gly a R 1 denotes B31Arg-B32Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Ala a R 1 denotes B31Arg-B32Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Thr a R 1 denotes B31Arg-B32Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Ser a R 1 denotes B31Arg-B32Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes group NH 2 and R 1 denotes B31Arg-B32Arg, or R in the formula 1 denotes group NH 2 a R 1 denotes B31Arg-B32Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Gly a R 1 denotes B31Arg, or p 0 R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Ala a R 1 denotes B31 Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Thr a R 1 denotes B31Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Ser a R 1 denotes B31Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes group NH 2 and R 1 denotes B31Arg, or R in the formula 1 denotes group NH 2 a R 1 denotes B31Arg, or R in the formula 1 denotes group of formula Asn-R 2 , wherein R 2 denotes Gly, R 1 denotes B31 Lys-B32Arg, and B3Asn has been replaced with B3Glu.
[0034] As described before, in the case of glargin the problem of low stability has been solved by replacing asparagine in the position A21 with glycine. Research, which aimed at obtaining an insulin analogue exhibiting prolonged activity and stability in acidic injection solutions as described in the invention, went in different direction. In order to block carboxyl group responsible for low stability, there were obtained new derivatives of lizarginsulin with carboxyl group in asparagine residue modified in different ways, using methods of genetic engineering and enzymatic transformation. As a result of the conducted research it unexpectedly turned out, that chemical and biological properties, similar to these of glargine and lizargine derivative, are exhibited by derivatives of human insulin of formula 1, where chain A has been elongated at C terminus with a residuum of neutral amino acid (A22) or where carboxyl group of asparagine or cysteine at C terminus of chain A has been transformed into carboxyamid group, and to the C terminus of chain B there were attached residues of lysine and arginine (B31Lys-B32Arg), or two arginine residues (B31Arg-B32Arg), or one arginine residue (B31Arg). New analogues obtained in such a way are characterised by proper stability in acidic injection solutions (pH 3.5-5) and at the same time exhibit desired biological activity.
[0035] Introduced modification unexpectedly led to obtaining stable pharmaceutical compositions of insulin derivatives, at the same time preserving biological activity and causing a shift of isoelectric point to pH between 5 and 8, therefore reducing solubility of the new insulin derivative in physiological pH at the place of injection. This causes precipitation of insulin derivative microdeposit in subcutaneous tissue and subsequently slow release of the substance to the blood, which causes maintaining of theraupetical level by a prolonged time.
[0036] Properties of these compounds and their compositions have been confirmed by stability research and by researching their activity in animals with experimental diabetes. During these there was unexpectedly found remarkably prolonged effect of hypoglycaemic activity, which lasted also for a long time after stopping administration of the medicine, in contrast to what was observed for a reference commercially available insulin derivative of prolonged activity. This allows supposing, that properties of derivatives, which are the subject of the invention, will enable significantly less frequent administration of the medicine, which will increase effectiveness, safety and comfort of the patients therapy. It is also important, that start of activity of the new derivatives according to the invention is practically immediate, which means that these compounds unexpectedly exhibit characteristics of biological activity of known insulin analogues of both accelerated and prolonged activity.
[0037] Examples of insulin derivatives of formula 1 are such as, but not limited to, these exhibited below.
[0000] A22Gly -human insulin- B31LysB32Arg (insulin GKR) A22Ala -human insulin- B31LysB32Arg (insulin AKR) A22Ser -human insulin- B31LysB32Arg (insulin SKR) A22Thr -human insulin- B31LysB32Arg (insulin TKR) de(A21Asn)A20Cys-NH 2 -human insulin- B31LysB32Arg (insulin XKR) A21Asn-NH 2 -human insulin- B31LysB32Arg (insulin ZKR) A22Gly -human insulin- B3GluB31LysB32Arg (insulin GEKR) A22Gly -human insulin- B31ArgB32Arg (insulin GRR) A22Ala -human insulin- B31ArgB32Arg (insulin ARR) A22Ser -human insulin- B31ArgB32Arg (insulin SRR) A22Thr -human insulin- B31ArgB32Arg (insulin TRR) de(A21Asn)A20Cys-NH 2 -human insulin- B31ArgB32Arg (insulin XRR) A21Asn-NH 2 -human insulin- B31ArgB32Arg (insulin ZRR) A22Gly -human insulin- B31Arg (insulin GR) A22Ala -human insulin- B31Arg (insulin AR) A22Ser -human insulin- B31Arg (insulin SR) A22Thr -human insulin- B31Arg (insulin TR) de(A21Asn)A20Cys-NH 2 -human insulin- B31Arg (insulin XR) A21Asn-NH 2 -human insulin- B31Arg (insulin ZR)
To simplify names of recombined human insulin analogues, which are the subject of the invention, they were assigned symbols which are composed of the name “insulin” and 2-4 capital letters of alphabet, which denote amino acid residues, which were added or which replaced these present in the parent particle of human insulin. In the most cases these letters are consistent with one-letter amino acid residues code recognised in the literature. Only for two residues, that do not occur naturally, there were used additional letters, namely “Z” and “X”. In both cases the letter denotes a residue placed at C terminus of chain A, which where instead of the terminal COOH group there's CONH 2 group; letter “Z” denotes corresponding asparagine amide (that is A21Asn-NH 2 ), and letter “X”—cysteine amide (that is de(A21 Asn)A20Cys-NH 2 ).
[0038] Insulin analogues of formula 1 were produced by a series of genetic manipulations using standard methods of genetic engineering.
[0039] To this end there were constructed modifications of the gene encoding recombined human proinsulin using genetic techniques such as for example site specific mutagenesis. Site-specific mutagenesis reaction has been performed using Stratagene kit (cat. no. 200518-5), as a template has been used plasmid DNA pIGALZUINS-p5/ZUINS or pIGTETZUINS-p6/ZUINS. Also any other DNA containing proper sequence encoding recombined human proinsulin or preproinsulin can be used as the template.
[0040] According to the invention, in the light of recognised terminology, recombined human proinsulin is understood as a polypeptide chain where chains A and B of human insulin are connected by dipeptide Lys-Arg or Arg-Arg, and the recombined preproinsulin—a combination of proinsulin and an additional leader polypeptide, for example ubiquitin, or SOD or their fragments.
[0041] Reaction mixture was used to transform competent cells of a proper Escherichia coli strain, as for example DH5α, DH5, or HB101, however it is possible to use cells of other E. coli strains or cells of other microorganisms, or other known cell lines which can be used for expression of recombined proteins. Plasmid containing given modification of a gene encoding recombined human proinsulin was isolated and sequenced in order to verify correctness of nucleotide sequence. According to the variant of the invention, plasmid with the modified gene encoding recombined human proinsulin was used to transform competent E. coli DH5a cells and bacteria were cultured in LB media with addition of selection antibiotic (0.01 mg/ml) in the volume of 500 ml, at temp. 37° C., 200 rpm for 18 h. Bacterial material was prepared for strain bank, samples in proportion 1:1 of bacteria culture and 40% glycerol were deposited at −70° C.
[0042] Variants of recombined preproinsulin obtained by expression in E. coli strains were isolated in the form of inclusion bodies, after the cells had been disintegrated, and subsequently were subjected to standard processes of fusion proteins purification. Solution of hybrid protein with insulin analog obtained after renaturation was subjected to controlled treatment with tripsine, analogously to case of many methods known beforehand and described e.g. by Kemmlera et al. in J. Biol. Chem., Vol. 246, page 6786-6791 (1971) or patents U.S. Pat. No. 6,686,177 and U.S. Pat. No. 6,100,376. Obtained insulin analogues were subjected to the process of purification using known methods, mainly low-pressure chromatography, ultrafiltration and/or HPLC. The product was precipitated from sufficiently purified solution of insulin analogue.
[0043] In order to obtain derivatives containing at the C terminus of chain A residue A21Asn-NH 2 or A20Cys-NH 2 , there were used α-amidating enzymes (α-AE), catalysing conversion of naturally appearing in living organisms prohormones, which are reaction substrates converted into active α-amid forms.
[0044] Enzyme PAM (peptidylglycine α-amidating monooxygenase) is a protease with dual activity, denoted as activity PHM (Peptidylglycine alpha-hydroxylating monooxygenase) and PAL (peptidylamidoglycolate lyase activity) (Diagram 1), which enables obtaining C terminal amide. It was investigated, that half of peptide hormones, such as oxytocin or vasopressin require achieving their optimal activity a C-terminal amid group. In this reaction the amid group originates from C-terminal gycine residue, which is here direct reaction precursor (Satani M., Takahashi K., Sakamoto H., Harada S., Kaida Y., Noguchi M.; Expression and characterization of human bifunctional peptidylglycine alpha-amidating monooxygenase. Protein Expr Purif. 2003 April; 28(2):293-302.; Miller D. A., Sayad K. U., Kulathila R., Beaudry G. A., Merkler D. J., Bertelsen A. H.; Characterization of a bifunctional peptidylglycine alpha-amidating enzyme expressed in Chinese hamster ovary cells. Arch Biochem Biophys. 1992 Nov. 1; 298(2):380-8).
[0000]
[0000] Diagram 1 Outline of α-amidation of a peptide by active PAM protease (according to Satani M., Takahashi K., Sakamoto H., Harada S., Kaida Y., Noguchi M.; Expression and characterization of human bifunctional peptidylglycine alpha-amidating monooxygenase. Protein Expr Purif. 2003 April; 28(2):293-302.).
[0045] PAM protease is a protein which is found inter alia in eukaryotic organisms of different length of amino acid chain. In this project there was used a protease originating from human organism (Homo sapiens), in which there are found 6 genes encoding proteins exhibiting activity of α-amidating protease.
[0046] The basic physicochemical property of recombined human insulin analogues of formula 1, which differentiates them from human insulin, is their value of isoelectric point, which has values from about 5 to about 8. This means good solubility of the compounds in solutions of acidic to slightly acidic pH. This property enabled preparation of composition—solutions of new insulin derivatives in acidic pH.
[0047] An aspect of the invention is also pharmaceutical composition characterised by this, that it contains effectively acting amount of insulin derivative according to the invention or its pharmaceutically acceptable salt, which are defined above. Favourably, the pharmaceutical composition according to the invention contains also from 10 to 50 μg/ml of zinc.
[0048] Consecutive aspect of the invention is also use of insulin derivative according to the invention or its pharmaceutically acceptable salt, which were defined above, to manufacture drug for treatment or prevention of diabetes.
[0049] In accordance with the above, the pharmaceutical composition, according to the invention, contains effectively acting amount of biosynthetic analogue of human insulin of formula 1 or its pharmacologically acceptable salt and auxiliary substances.
[0050] A salt of biosynthetic human insulin analogue according to the invention can be for example a salt of alkaline metal or ammonium salt.
[0051] Intended for administration composition according to the invention is prepared in the form of solution and contains: effectively acting amount of biosynthetic analogue of human insulin of formula 1 or its pharmacologically acceptable salt and auxiliary substances, such as: isotonic agents, preservatives agents, stabilizing agents, optionally buffering agents.
[0052] Amount of the active substance used in the composition according to the invention is about 1-1600, favourably 10-1200, especially favourably 10-500 u/ml. In case of each human insulin analogue, which is subject of this invention, by 1 unit (1 u) is meant 1 auxiliary unit, containing the same number of moles of the analogue as 1 international unit of insulin, corresponding to 6 nMol (that is 6×10 −9 Mol).
[0053] For pharmaceutical composition according to the invention pH value of the solution is from about 3.5 to about 5, favourably 4.0-4.5.
[0054] Generally, auxiliary substances in compositions according to the invention are the same substances that are used in preparations containing known recombined human insulin.
[0055] Isotonic substance according to the invention can be any substance, which allows obtaining solution isoosmotic in respect to human blood plasma. To typical isotonic agents used in pharmacy belong such substances as sodium chloride, mannitol, glycine, preferably glycerine. Favourable is use of glycerine.
[0056] Useful conserving agents to be used in composition according to the invention are compounds chosen from the group to which belongs m-cresole, phenol or their mixtures. New derivatives, similarly to recombined normal human insulin, are stabilised by addition of zinc ions, introduced into the solution in the form of, among other, zinc chloride or oxide. Amount of the zinc can range from around 5 μg/ml to around 150 μg/ml.
[0057] A following example of a content of the composition containing derivatives of recombined human insulin according to the invention has been developed: 10-500 u/ml of biosynthetic analogue of human insulin of formula 1 or its pharmacologically acceptable salt, 16 mg/ml of glycerine, 2.7-3 mg/ml m-cresole, 10-50 μg/ml of zinc and water for injection to 1 ml.
BRIEF DESCRIPTION OF DRAWINGS
[0058] To better explain the essence of the invention this description has been extended with a detailed discussion of examples of the invention's realisation, which encompasses also enclosed list of sequences and figures, of which:
[0059] FIG. 1 presents structure of plasmid p5/ZUINSGly(22A) containing a gene encoding GKR protein of recombined insulin.
[0060] FIGS. 2A-2E present nucleotide and amino acid sequence of plasmid p5/ZUINSGly(22A).
[0061] FIG. 3 presents structure of plasmid p6/ZUINSSer(22A) containing a gene encoding insulin SKR protein.
[0062] FIGS. 4A-4D present nucleotide and amino acid sequence of plasmid p6/ZUINSSer(22A).
[0063] FIG. 5 presents influence of single dose administration of GKR insulin (in the dose of 5 u/kg of body mass on glucose concentration in blood of normoglycaemic rats, compared with preparation of Gensulin N. Average values±SEM. Statistical significance **p<0.01: Insulin GKR vs. initial glucose concentration; ##p<0.01, #p<0.05: Gensulin N vs. initial glucose concentration; ̂̂p<0.01: Insulin GKR vs. Gensulin N.
[0064] FIG. 6 presents influence of single dose administration of GKR insulin (in dose of 5 u per kg of body mass) on glucose concentration in blood of rats with mild streptozotocin-induced diabetes (in comparison with Lantus preparation). 0—fixed hyperglycaemia; control—physiological salt solution 10 μl/200 g bm. Statistical significance: **p<0.01, *p<0.05 GKR vs. Lantus;
[0065] FIG. 7 presents influence of single dose administration of GKR insulin (in doses of 2.5 u, 5 u and 7.5 u per kg of body mass) on glucose concentration in blood of rats with severe streptozotocin-induced diabetes. 0—fixed hyperglycaemia; control—physiological salt solution 10 μl /200 g bm. Statistical significance: **p<0.01 *p<0.05 GKR 2.5 u vs control; ̂̂p<0.01 ̂p<0.05 GKR 5 u vs control; ##p<0.01 #p<0.05 GKR 7.5 u vs control
[0066] FIG. 8 presents influence of single dose administration of GKR insulin (in dose of 7.5 u per kg of body mass) on glucose concentration in blood of rats with severe streptozotocin-induced diabetes (in comparison with Lantus preparation). 0—fixed hyperglycaemia; control—physiological salt solution 10 μl/200 g bm. Statistical significance: **p<0.01, *p<0.05 GKR vs. Lantus;
[0067] FIG. 9 presents glucose concentration in blood of rats after multiple administrations of GKR insulin in doses of 5 u per kg of body mass in a model of mild streptozotocin-induced diabetes (in comparison with Lantus preparation); 0—fixed hyperglycaemia; control—physiological salt solution 10 μl/200 g bm.
[0068] FIG. 10 presents glucose concentration in blood of rats in the period after stopping administration of GKR insulin in dose of 5 u per kg of body mass in a model of mild streptozotocin-induced diabetes (in comparison with Lantus preparation);
[0069] FIG. 11 presents influence of single dose administration of GR insulin (in doses of 10 u per kg of body mass) on glucose concentration in blood of rats with moderate streptozotocin-induced diabetes compared with Lantus preparation. 0—fixed hyperglycaemia; control—physiological salt 10 μl/200 g bm. 0—fixed hyperglycaemia; control—physiological salt solution 10 μl/200 g bm. Statistical significance: **p<0.01, *p<0.05 GR vs. Lantus;
[0070] FIG. 12 presents influence of single dose administration of GEKR insulin (in dose of 10 u per kg of body mass) on glucose concentration in blood of rats with moderate streptozotocin-induced diabetes compared with Levemir preparation. 0—fixed hyperglycaemia;
DETAILED DESCRIPTION
EXAMPLE 1
Construction of p5/ZUINSGly(22A) Plasmid and Obtaining of a Strain Transformed With this Plasmid
[0071] To construct a gene encoding recombined INSGly(22A) proinsulin there was used p5/ZUINS plasmid, in which a DNA fragment encoding recombined insulin precursor is added to a modified gene of synthetic ubiquitin. In the ubiquitin gene arginine codons have been replaced with alanine codons and to the C terminus of ubiquitin gene there has been added additional arginine codon. Peptide which constitutes part of ubiquitin is a carrier for insulin precursor, and is a condition for high efficiency of fusion protein synthesis in E. coli. The region encoding the modified fusion protein ubiquitin-human insulin is placed under control of pms (WO05066344 A2) promoter. The plasmid carries ampicillin resistance gene. For construction of p5/ZUINS vector there was used pIGAL1 plasmid, whose sequence deposited in Gene Bank has number AY424310.
[0072] The recombined INSGly(22A) proinsulin gene differs from the model human proinsulin gene in such a way, that it has attached additional GGT codon at C terminus of chain A. In result amino acid sequence of chain A is being elongated at position 22 with Gly-glycine-amino acid residue.
[0073] In order to modify the gene encoding human recombined proinsulin sequence by adding of GGT (Gly) codon at its C terminus, there were designed following primers for point mutagenesis reaction:
[0000]
GLYG
5′ AACTACTGCAAT GGT T AA GTCGACTCTAGC 3′
Gly STOP
GLYD
5′ GTAGCTAGAGTCGACTTA ACC ATTGCAG 3′
Gly
[0074] The point mutagenesis reaction was carried out using Stratagene kit (catalogue no 200518-5). As the template there has been used plasmid DNA p5/ZUINS. Escherichia coli DH5 α competent cells were transformed with reaction mixture. Plasmid p5/ZUINSGly(22A) has been isolated and sequenced in order to verify presence of GGT nucleotides encoding glycine and the validity of plasmid sequence. Plasmid with the modified gene encoding recombined p5/ZUINSGly(22A) proinsulin has been used in transformation of competent E. coli DH5a cells which were subsequently cultivated for 18 hours in LB medium with addition of ampicillin (0.01 mg/ml) in the volume of 500 ml, at 37° C., 200 rpm. Bacteria material has been prepared for strain bank, samples containing 1:1 bacterial cultures and 40% glycerol have been deposited at −70° C.
[0075] Obtained Escherichia coli strain constitutes the initial biological material in the process of obtaining GKR insulin via biosynthesis, according to Example 10.
[0000] Genetic Construction of p5/ZUINSGly(22A) Plasmid
[0076] Plasmid p5/ZUINSGly(22A) is 4775 base pairs long and is built of following regulatory sequences and genes:
from 374 bp to 1234 bp there is ampicillin resistance gene AMP R, from 4158 bp to 4323 bp there is a region encoding pms promoter, from 4327 bp to 4554 bp there is a sequence encoding modified synthetic ubiquitin gene ZUBI, from 4558 bp to 4722 bp there is a sequence encoding the recombined INSGly(22A) proinsulin gene, from 4729 bp to 4775 bp there is a region encoding transcription terminator Ter. Structure of p5/ZUINSGly(22A) plasmid containing the gene encoding recombined human insulin protein (GKR insulin) is shown schematically in FIG. 1 , and its nucleotide and amino acid sequence at FIG. 2 .
EXAMPLE 2
Construction of p5/ZUINSGly(22A)Arg(31B) Plasmid and Obtaining a Strain Transformed With It
[0082] In construction of recombined INSGly(22A)Arg(31B) proinsulin gene there was used p5/ZUINSGly(22A) plasmid. The recombined INSGly(22A)Arg(31B) gene is characterised by replacement of AAG (Lys) codon with CGT (Arg) codon at position 31 of chain B.
[0083] In order to modify the gene encoding sequence of recombined INSGly(22A) proinsulin there were designed following primers for point mutagenesis reaction:
[0000] ARGG 5′ CTAAAACA CGT CGCGGCATCGTTGAACAG 3′ Arg ARGD 5′ CGATGCCGCG ACG TGTTTTAGGAGTGTAG 3′ Arg
Stratagene kit (cat. no 200518-5) has been used to conduct point mutagenesis reaction. Isolation, verification of validity of plasmid nucleotide sequence and obtaining E. coli DH5α bacteria with p5/ZUINSGly(22A)Arg(31B) plasmid have been performed as in Example 1. Obtained Escherichia coli strain is the initial biological material in the process of manufacturing GR insulin via the biosynthesis according the Example 11.
EXAMPLE 3
Construction of p5/ZUINSSer(22A)Arg(31B) Plasmid and Obtaining of a Strain Transformed With It
[0084] To construct a gene of recombined INSSer(22A)Arg(31B) proinsulin there was used p5/ZUINSGly(22A)Arg(31B) plasmid. The difference between the gene encoding recombined INSSer(22A)Arg(31B) proinsulin and the gene encoding recombined proinsulin INSGly(22A)Arg(31B) is a replacement of GGT (Gly) codon with TCT (Ser) codon at position 22 of chain A.
[0085] In order to modify the gene encoding the sequence of recombined INSGly(22A)Arg(31B) proinsulin by replacement of GGT (Gly) with TCT (Ser) codon at position 22 of chain A, there were designed following primers for point mutagenesis reaction:
[0000] SERG 5′ CAAT TCT TAA GGATCCTCTAG 3′ Ser STOP SERD 5′ CTTA AGA ATTGCAGTAGTTCTCCAG 3′ Ser
Stratagene kit (cat. no 200518-5) has been used to conduct point mutagenesis reaction. Isolation, verification of validity of plasmid nucleotide sequence and obtaining E. coli DH5α bacteria with p5/ZUINSSer(22A)Arg(31B) plasmid have been performed as in Example 1. Obtained Escherichia coli strain is the initial biological material in the process of manufacturing SR insulin via biosynthesis according to Example 12.
EXAMPLE 4
Construction of p5/ZUINSAla(22A) Plasmid and Obtaining of a Strain Transformed With It
[0086] To construct a gene of recombined INSAla(22A) proinsulin there has been used p5/ZUINS plasmid. The difference between the gene of recombined INSAla(22A) proinsulin and the model human proinsulin gene is addition of GCT codon to the C terminus of chain A of the former. In result the amino acid sequence of chain A is elongated at position 22 with Ala-alanine amino acid residue.
[0087] In order to modify the gene encoding the sequence of recombined human insulin by addition of GCT (Ala) codon at its C terminus, there were designed following primers for point mutagenesis:
[0000] ALAG 5′ CAAT GCT TAA GGATCCTCTAG 3′ Ala STOP ALAD 5′ CTTA AGC ATTGCAGTAGTTCTCCAG 3′ Ala
Stratagene kit (cat. no 200518-5) has been used to conduct point mutagenesis reaction. Isolation, verification of validity of plasmid nucleotide sequence and obtaining E. coli DH5α bacteria with p5/ZUINSAla(22A) plasmid have been performed as in Example 1.
[0088] Obtained Escherichia coli strain is the initial biological material in the process of manufacturing AKR insulin via biosynthesis according to Example 13.
EXAMPLE 5
Construction of p5/ZUINSGly(22A)Glu(3B) Plasmid and Obtaining of a Strain Transformed With It
[0089] To construct a gene of recombined p5/ZUINSGly(22A)Glu(3B) proinsulin there was used p5/ZUINSGly(22A) plasmid. The difference between the gene encoding recombined INSGly(22A)Glu(3B) proinsulin and the gene encoding recombined INSGly(22A) proinsulin is a replacement of AAC (Asn) codon with GAA (Glu) codon at position 3 of chain B.
[0090] In order to modify the gene encoding the sequence of recombined INSGly(22A) proinsulin by replacement of AAC (Asn) with GAA (Glu) codon at position 3 of chain B, there were designed following primers for point mutagenesis reaction:
[0000] GLUG 5′ GTC GAA CAGCACCTGTGTGGTTC 3′ Glu GLUD 5′ GCTG TTC GACAAAACGAGGACCTGC 3′ Glu
Stratagene kit (cat. no 200518-5) has been used to conduct point mutagenesis reaction. Isolation, verification of validity of plasmid nucleotide sequence and obtaining E. coli DH5α bacteria with p5/ZUINSGly(22A)Glu(31 B) plasmid have been performed as in Example 1.
[0091] Obtained Escherichia coli strain is the initial biological material in the process of manufacturing GEKR insulin via biosynthesis according to Example 14.
[0092] In examples 1-5 as the plasmid hosts there have been used DH5 α E. coli bacteria, but in described above, model realisation of the invention there can be used also other E. coli strains, for example DH5 or HB101.
EXAMPLE 6
Construction of p6/ZUINSSer(22A) Plasmid and Obtaining of a Strain Transformed With It
[0093] To construct a gene encoding recombined INSSer(22A) proinsulin there was used p6/ZUINS plasmid, in which DNA fragment encoding precursor of recombined insulin is appended to modified gene encoding synthetic ubiquitin. In the ubiquitin-encoding gene arginine codons have been replaced with alanine codons and to the C terminus of ubiquitin gene there has been added an additional arginine codon. The peptide constituting part of ubiquitin is a carrier for insulin precursor, which conditions high efficiency of fusion protein expression in E. coli. The region encoding the modified ubiquitin-human insulin fusion protein is placed under control of pms promoter (WO05066344 A2). The plasmid carries tetracycline resistance gene. To construct p6/ZUINS vector there has been used p5/ZUINS plasmid.
[0094] The difference between the gene encoding recombined INSSer(22A) proinsulin and the model human proinsulin gene is that the former has appended additional TCT codon at C terminus of chain A. In result amino acid sequence of chain A is elongated at position 22 with Ser-serine amino acid residue.
[0095] In order to modify the gene encoding the sequence of recombined proinsulin by appending TCT (Ser) codon at its C terminus, there were designed following primers for point mutagenesis reaction:
[0000] SKRG 5′ GAACTACTGCAAT TCT TAA GTCGA 3′ Ser STOP SKRD 5′ TAGAGTCGACTTA AGA ATTGCAGTA3′ Ser
Stratagene kit (cat. no 200518-5) has been used to conduct point mutagenesis reaction, as the template has been used p6/ZUINS plasmid DNA. Escherichia coli DH5α competent cells have been transformed with the reaction mixture. p6/ZUINSSer(22A) plasmid has been isolated and sequenced in order to verify presence of TCT nucleotides encoding serine and correctness of the plasmid sequence. The plasmid with the modified gene encoding p6/ZUINSSer(22A) proinsulin has been used to transform E. coli DH5α bacteria. Subsequently the bacteria were cultivated for 18 hours in LB media with addition of tetracycline (0.01 mg/ml) in 500 ml volume at 37° C., 200 rpm. Bacteria material has been preparated for strain bank samples containing 1:1 bacterial cultures and 40% glycerol have been deposited at −70° C.
[0096] Obtained Escherichia coli strain constitutes initial biological material in the process of manufacturing SKR insulin via biosynthesis according to Example 15.
[0097] Genetic Construction of p6/ZUINSSer(22A) Plasmid
[0098] p6/ZUINSSer(22A) plasmid is 4911 base pairs long and is made of following regulatory sequences and genes:
from 146 by to 1336 bp there is a tetracycline resistance gene TET R, from 4304 by to 4469 bp there is a region encoding pms promoter, from 4473 by to 4703 bp there is a region encoding the gene encoding the modified synthetic ubiquitin; there are following modifications: replacement of arginine amino acid at positions 42, 54, 72, 74 in the ubiquitin gene with alanine and addition of arginine at position 77 which allows to remove the ubiquitin, from 4704 by to 4868 bp there is a sequence encoding the gene encoding recombined INSSer(22A) proinsulin, from 4875 by to 4911 bp there is a region encoding transcription terminator Ter. Structure of p6/ZUINSSer(22A) plasmid containing the gene encoding recombined human insulin protein (SKR protein) is shown schematically in FIG. 3 , and its nucleotide and amino acid sequence in FIG. 4 .
EXAMPLE 7
Construction of p6/ZUINSGly(22A) Plasmid and Obtaining of a Strain Transformed With It
[0104] To construct a gene encoding recombined INSGly(22A) proinsulin there was used p6/ZUINS plasmid, in which DNA fragment encoding precursor of recombined insulin is appended to modified gene encoding synthetic ubiquitin.
[0105] The difference between the gene encoding recombined INSGly(22A) proinsulin and the model human proinsulin gene is that the former has appended additional GGT codon at C terminus of chain A. In result amino acid sequence of chain A is elongated at position 22 with Gly-glycine amino acid residue.
[0106] In order to modify the gene encoding the sequence of recombined human proinsulin by appending GGT (Gly) codon at its C terminus, there were designed following primers for point mutagenesis reaction:
[0000] GLYG 5′ AACTACTGCAAT GGT TAA GTCGACTCTAGC 3′ Gly STOP GLYD 5′ GTAGCTAGAGTCGACTTA ACC ATTGCAG3′ Gly
Stratagene kit (cat. no 200518-5) has been used to conduct point mutagenesis reaction. Isolation, verification of validity of plasmid nucleotide sequence and obtaining E. coli DH5 bacteria with p6/ZUINSGly(22A) plasmid have been performed as in Example 6.
[0107] Obtained Escherichia coli strain constitutes initial biological material in the process of manufacturing GKR insulin via biosynthesis according to Example 16.
EXAMPLE 8
Construction of p6/ZUINSGly(22A)Glu(3B) Plasmid and Obtaining of a Strain Transformed With It
[0108] To construct a gene of recombined INSGly(22A)Glu(3B) proinsulin there has been used p6/ZUINSGly(22A) plasmid. The difference between the gene of recombined INSGly(22A)Glu(3B) proinsulin and the recombined INSGly(22A) proinsulin gene is replacement of AAC (Asn) codon with GAA (Glu) codon at position 3 of chain B.
[0109] In order to modify the gene encoding the sequence of recombined INSGly(22A) proinsulin by replacement of AAC (Asn) codon with GAA (Glu) codon at position 3 in chain B, there were designed following primers for point mutagenesis:
[0000] GLUG 5′ GTC GAA CAGCACCTGTGTGGTTC 3′ Glu GLUD-2 5′ CACAGGTGCTG TTC GACAAAACGACC 3′ Glu
Stratagene kit (cat. no 200518-5) has been used to conduct point mutagenesis reaction. Isolation, verification of validity of plasmid nucleotide sequence and obtaining E. coli DH5 bacteria with p6/ZUINSGly(22A)Glu(31 B) plasmid have been performed as in Example 6.
[0110] Obtained Escherichia coli strain is the initial biological material in the process of manufacturing GEKR insulin via biosynthesis according to Example 17.
EXAMPLE 9
Construction of p6/ZUINSGly(22A)Arg(31 B) Plasmid and Obtaining of a Strain Transformed With It
[0111] To construct a gene of recombined INSGly(22A)Arg(31 B) proinsulin there has been used p6/ZUINSGly(22A) plasmid. The gene encoding recombined INSGly(22A)Arg(31 B) proinsulin is characterised by this, that it has replaced AAG (Lys) codon with CGT (Arg) codon at position 31 of chain B.
[0112] In order to modify the gene encoding the sequence of recombined INSGly(22A) proinsulin there were designed following primers for point mutagenesis:
[0000] ARGG 5′ CTAAAACA CGT CGCGGCATCGTTGAACAG 3′ Arg ARGD 5′ CGATGCCGCG ACG TGTTTTAGGAGTGTAG 3′ Arg
Stratagene kit (cat. no 200518-5) has been used to conduct point mutagenesis reaction. Isolation, verification of validity of plasmid nucleotide sequence and obtaining E. coli DH5 bacteria with p6/ZUINSGly(22A)Arg(31 B) plasmid have been performed as in Example 6.
[0113] Obtained Escherichia coli strain is the initial biological material in the process of manufacturing GR insulin via biosynthesis according to Example 18.
EXAMPLE 10
Manufacturing of GKR Insulin
[0114] GKR insulin has been manufactured in a biosynthesis process realised in the classical way (inoculum, seed culture, production culture) using Escherichia coli strain with a DNA fragment encoding GKR insulin precursor obtained according to Example 1. Production cultivation has been conducted in 150 dm 3 fermentation tank for 20 hours at 37° C., controlling pH, temperature, optical density, glucose concentration and aeration. In the fermentation conditions GKR analogue has been produced intracellulary in inclusion bodies. After the end of fermentation the fermentation broth has been concentrated and subsequently digested with lysosyme and bacterial cells have been subjected to disintegration. Obtained suspension has been diluted with water and after incubation with Triton centrifuged. Created raw deposit of inclusion bodies was initially purified, finally obtaining inclusion bodies homogenate.
[0115] The obtained homogenate has been dissolved (10-15 mg/cm 3 ) in the solution of sodium carbonate with addition of EDTA, subjected to renaturation and, for protection of lysine free amino groups, subjected to reversible process of citraconylation in a reaction with citraconic anhydride. The dissolved protein had been subjected to trypsine digestion in order to cleave the leader protein out and to cleave the insulin chains. In the result of trypsine activity there was obtained GKR insulin. The solution after digestion with trypsine has been subjected to purification with low pressure liquid chromatography on DEAE Sepharose FF gel, and subsequently diafiltration and concentration—second low pressure liquid chromatography on Q Sepharose FF gel. Main fraction has been subjected to purification with high pressure liquid chromatography on Kromasil-RPC8 100A 10 μm gel. Main fraction has been concentration using dialysis to concentration of 30-40 mg/cm 3 and purified GKR insulin has been separated by crystallisation, using sodium citrate, zinc acetate, citric acid. From one batch of inclusion bodies has been obtained about 5.4 g of crystallised GKR insulin of HPLC purity 97%.
[0116] The product's structure has been confirmed by following data:
molecular mass determined by mass spectroscopy is equal to 6149 and conforms to the theoretical value (6149.1); peptide map: conforms; sequence and amino acid composition: conforming to theoretical.
Isoelectric point determined by capillary electrophoresis is 7.19.
EXAMPLE 11
Manufacturing of GR Insulin
[0120] Proceeding analogously to Example 10, using Escherichia coli strain with DNA fragment encoding GR insulin precursor, obtained in accordance with Example 2, there has been obtained from analogous batch of inclusion bodies 5.2 g of GR insulin of HPLC purity equal to 97.5%.
[0121] Product's structure has been confirmed by following data:
molecular mass determined by mass spectroscopy equals 6021 and conforms to theoretical value (6020.9); peptide map: conforms, sequence and amino acid composition: conform to theoretical.
Isoelectric point: 6.39.
EXAMPLE 12
Manufacturing of SR Insulin
[0125] Proceeding analogously to Example 10, using Escherichia coli strain with DNA fragment encoding SR insulin precursor, obtained in accordance with Example 3, there has been obtained from analogous batch of inclusion bodies 5.5 g of SR insulin of HPLC purity equal to 97%.
[0126] Product's structure has been confirmed by following data:
molecular mass determined by mass spectroscopy equals 6051 and conforms to theoretical value (6050.9); peptide map: conforms,
Isoelectric point: 6.55.
EXAMPLE 13
Manufacturing of AKR Insulin
[0129] Proceeding analogously to Example 10, using Escherichia coli strain with DNA fragment encoding AKR insulin precursor, obtained in accordance with Example 4, there has been obtained from analogous batch of inclusion bodies 4.7 g of AKR insulin of HPLC purity equal to 96.5%.
[0130] Product's structure has been confirmed by following data:
molecular mass determined by mass spectroscopy equals 6163 and conforms to theoretical value (6163.1); peptide map: conforms.
Isoelectric point: 7.07.
EXAMPLE 14
Manufacturing of GEKR Insulin
[0133] Proceeding analogously to Example 10, using Escherichia coli strain with DNA fragment encoding GEKR insulin precursor, obtained in accordance with Example 5, there has been obtained from analogous batch of inclusion bodies 5.0 g of GEKR insulin of HPLC purity equal to 97.5%.
[0134] Product's structure has been confirmed by following data:
molecular mass determined by mass spectroscopy equals 6164 and conforms to theoretical value (6164.1); peptide map: conforms.
Isoelectric point: 6.29.
EXAMPLE 15
Manufacturing of SKR Insulin
[0137] Proceeding analogously to Example 10, using Escherichia coli strain with DNA fragment encoding SKR insulin precursor, obtained in accordance with Example 6, there has been obtained from analogous batch of inclusion bodies 5.3 g of SKR insulin of HPLC purity equal to 98%.
[0138] Product's structure has been confirmed by following results:
molecular mass determined by mass spectroscopy equals 6179 and conforms to theoretical value (6179.1); peptide map: conforms,
Isoelectric point: 7.05.
EXAMPLE 16
Manufacturing of GKR Insulin
[0141] Proceeding analogously to Example 10, using Escherichia coli strain with DNA fragment encoding GKR insulin precursor, obtained in accordance with Example 7, there has been obtained from analogous batch of inclusion bodies 6.3 g of GKR insulin of HPLC purity equal to 95.5%.
[0142] Remaining properties of the product (GKR insulin) as in Example 10.
EXAMPLE 17
Manufacturing of GEKR Insulin
[0143] Proceeding analogously to Example 10, using Escherichia coli strain with DNA fragment encoding GEKR insulin precursor, obtained in accordance with Example 8, there has been obtained from analogous batch of inclusion bodies 6.0 g of GEKR insulin of HPLC purity equal to 97%.
[0144] Remaining properties of the product (GEKR insulin) as in Example 14.
EXAMPLE 18
Manufacturing of GR Insulin
[0145] Proceeding analogously to Example 10, using Escherichia coli strain with DNA fragment encoding GR insulin precursor, obtained in accordance with Example 9, there has been obtained from analogous batch of inclusion bodies 5.5 g of GR insulin of HPLC purity equal to 96.5%.
[0146] Remaining properties of the product (GR insulin) as in Example 11.
EXAMPLE 19
Manufacturing of ZKR Insulin
[0147] To 1000 ml of GKR insulin solution manufactured according to Example 10 or 16 (concentration 0.1 mg/ml), in 100 mM MES/KOH buffer pH 5.0-5.5 there has been added 1μM CuSO 4 , 100 μg/ml catalase, 5 mM ascorbic acid and 2 μM PAM enzyme (obtained according to Satani M., Takahashi K., Sakamoto H., Harada S., Kaida Y., Noguchi M.; Expression and characterization of human bifunctional peptidylglycine alpha-amidating monooxygenase. Protein Expr Purif. 2003 April; 28(2):293-302.), and subsequently mixture have been left for 2 hours at 37° C. The reaction has been stopped by addition of 1 mM Na 2 EDTA.
[0148] After filtration the obtained solution has been subjected to purification with ion-exchange chromatography and HPLC methods.
[0149] Main fraction containing ZKR insulin concentrated and subjected to crystallisation using sodium citrate, zinc citrate, citric acid. From one batch of reaction mixture there has been obtained about 10 mg of crystalline ZKR insulin of HPLC purity of 97%. Product's structure has been confirmed by following results:
molecular mass determined by mass spectroscopy equals 6091 and conforms to theoretical value (6091.1); peptide map: conforms.
Isoelectric point: 7.54.
EXAMPLE 20
Manufacturing of ZR Insulin
[0152] To 100 ml of GR insulin solution, manufactured according to Example 11 or 18 (2 mg/ml), in 100 mM MES/KOH buffer, pH 4.5, there has been added 1 μM CuSO 4 , 100 μg/ml catalase, 5 mM ascorbic acid and 2 μM PAM enzyme, and subsequently the solution has been mildly mixed for 1 hour at 37° C. The reaction has been stopped by addition of 1 mM Na 2 EDTA. The solution after reaction with PAM has been subjected to purification by ion-exchange and HPLC methods.
[0153] The main fraction containing insulin concentrated and subjected to crystallisation using sodium citrate, zinc citrate, citric acid. From one batch of reaction mixture there was obtained 22 mg of crystalline ZR insulin of HPLC purity of 98%.
[0154] Product's structure has been confirmed by following results:
molecular mass determined by mass spectroscopy equals 5963 and conforms to theoretical value (5962.9); peptide map: conforms.
Isoelectric point: 6.97.
EXAMPLE 21
Manufacturing of Pharmaceutical Preparation of GKR Insulin (100 u/ml)
[0157] There was made 100 ml of pharmaceutical preparation of GKR insulin (100 u/ml) of following composition (values per 1.0 ml):
[0000] GKR insulin (Example 16) 3.69 mg/ml (as 100% substance, 100 u/ml) m-cresol 2.7 mg/ml anhydrous glycerine 16 mg/ml zinc 30 μg/ml water for injection to 10 ml pH 4.5
Preparation procedure was as follows:
[0158] There were made two following solutions:
Solution 1
[0000]
Zinc oxide in amount necessary to reach the final concentration of Zn ions of 30 μg/ml were dissolved in 40 ml of 10 mM hydrochloric acid. After that, to obtained solution was added insulin GKR in amount corresponding to 10 000 u of insulin GKR, under mild stirring until obtaining a clear solution and then pH adjusted to value 4,5.
Solution 2
[0000]
Separately, 270 mg of m-cresol and 1600 ml of anhydrous glycerol were dissolved in 40 ml water for injection.
Mixing of Solutions 1 and 2
[0161] Solution 1 was added under stirring to Solution 2, supplemented with water for injection to volume 100 ml and in case of need corrected pH to value 4.5 with 10 mM hydrochloric acid or 0.2 M solution of sodium hydroxide. Resulting mixture was in sterile condition filtered through 0.22 μm filter and aliquoted into glass 3 ml vials. It was determined that the preparation containing GKR insulin (100 u/ml) exhibits stability in room temperature investigated period of 56 days, in the accelerated stability test (Example 24).
EXAMPLE 22
Manufacturing of Pharmaceutical Preparation of GR Insulin (100 u/ml)
[0162] There was made 100 ml of pharmaceutical preparation of GR insulin (100 u/ml) of the following composition (values per 1.0 ml):
[0000] GR insulin 3.61 mg/ml (as 100% substance, 100 u/ml) (Example 11) m-cresol 2.7 mg/ml anhydrous glycerine 16 mg/ml zinc 30 μg/ml injection water up to 1.0 ml pH 4.0
The procedure was identical as in Example 21, apart of that that instead of GKR insulin there was used GR insulin (in the amount of 361 mg, 10 000 u) and that the final value of pH was 4.0.
EXAMPLE 23
Manufacturing of Pharmaceutical Preparation of GEKR Insulin (100 u/ml)
[0163] There was made 100 ml of pharmaceutical preparation of GEKR insulin (100 u/ml) of the following composition (values per 1.0 ml):
[0000] GEKR insulin 3.70 mg/ml (as 100% substance, 100 u/ml) (Example 14) m-cresol 2.7 mg/ml anhydrous glycerine 16 mg/ml zinc 30 μg/ml injection water up to 1.0 ml pH 4.0
The procedure was identical as in Example 21, apart of that that instead of GKR insulin there was used GEKR insulin (in the amount of, 10 000 u) and that the final value of pH was 4.0.
EXAMPLE 24
Examination of Accelerated Stability of Pharmaceutical Preparation of GKR Insulin (100 u/ml)
[0164] Pharmaceutical preparation of GKR insulin (100 u/ml), made according to Example 21, has been subjected to examination of accelerated stability (25° C.±2° C.). During this examination there were performed analysis of purity and level of protein contamination. Below there are exhibited HPLC purity of the product (GKR insulin) and the proportional contribution: highest single contamination, deamido derivative and polymers, in HPLC test, in time points of: “0”, 28, 42 and 56 days.
[0000]
HPLC purity test
“0”
28 days
42 days
56 days
Main peak [%]
95.10
94.33
93.98
93.60
Highest single contamination [%]
1.07
1.70
1.72
1.98
Deamido [%]
0.28
0.37
0.32
0.36
Polymers [%]
0.17
0.37
0.44
0.48
EXAMPLE 25
Examination of Accelerated Stability of Pharmaceutical Preparation of GEKR Insulin (100 u/ml)
[0165] Pharmaceutical preparation of GEKR insulin (100 u/ml), made according to Example 23, has been subjected to examination of accelerated stability (25° C.±2° C.). During this examination there were performed analysis of purity and level of protein contamination. Below there are exhibited HPLC purity of the product (GEKR insulin) and the proportional contribution: highest single contamination, and polymers, in HPLC test, in time points of: “0”, and 14 days and 1, 2 and 3 months.
[0000]
HPLC
14
2
purity test
“0”
days
1 months
months
3 months
Main peak[%]
97.33
97.14
96.42
94.55
94.41
Highest single
0.55
0.45
0.67
1.08
1.26
contamination
[%]
Polymers[%]
not de-
0.09
not
0.50
not
termined
determined
determined
EXAMPLE 26
Determination of GKR Activity on Normoglycaemic Animals
[0166] Recombined human insulin analogue (GKR insulin), similarly to Gensulin N (recombined isophane human insulin) exhibits prolonged activity time, and hypoglycaemic of normoglycaemic rats has similar course. Significant differences in hypoglycaemic activity of both preparations have been observed in 0.5 and 1 hour after administration. In this time there is observed fast and deep decrease of glucose concentration after GKR insulin. Peak activity of GKR insulin and Gensulin N is in 2 nd hour.
[0167] Initial research confirmed that GKR insulin is an active analogue of prolonged hypoglycaemic activity. Decrease in glucose level after GKR insulin administration was observed for up to 12 hours, while levels of glucose after 24 hours were similar to initial. Results of reaction of normoglycaemic rats to single administration of GKR insulin and Gensulin N preparations (taking into account mean values±SEM) are shown in Table 1 and FIG. 5 .
EXAMPLE 27
Determination of GKR Insulin Activity on Animals With Experimental Diabetes
[0168] Studies on experimental model of rat diabetes (induction with streptozotocin) confirmed irrefutably hypoglycaemic activity of GKR insulin. This activity has properties of prolonged activity.
[0169] After single dose administration, the lowering of glucose concentration in blood of the examined rats remains statistically significant up to 8 th -10 th hour (depending on intensity of diabetes and dose), in comparison with control. During the research there was demonstrated faster beginning of activity and faster achieving of peak activity (beginning 30 mins, peak 1-2 hours) by GKR insulin compared to the reference preparation—insulin glargine (Lantus).
[0170] Statistical significance of this phenomenon has been confirmed in severe and moderate diabetes.
[0171] Also the research of multiple dose administration of GKR insulin and the reference preparation of insulin glargine demonstrated similar activity of that both analogues. Administered for 21 days, three times per day, preparations caused improvement of glycaemy parameters in mild diabetes and, in principle, did not differ statistically in the intensity of the effect. The only difference was noticeably more equalised activity profile of GKR insulin.
[0172] Additionally there was observed very interesting phenomenon of long-lasting hypoglycaemic effect after termination of administration of GKR preparation. This observation has been conducted on 9 rats treated with GKR preparation and 3 treated with Lantus, of the group with mild diabetes, who were administered analogues in the dose of 5 u/kg bm for 21 days. Obtained results can be an evidence of existence of very strong bounding of GKR insulin in tissues (possibly subcutaneous tissue). They support thesis of existence of compartment, in which insulin is accumulated and slowly redistributed. This phenomenon was not observed for the reference preparation. This property, after its confirmation in humans, could be a breakthrough in therapy with prolonged activity insulin analogues, allowing e.g. administration of less than one dose of the medicine per day.
[0173] The results describing glucose concentration in rat blood after single dose administration of GKR insulin in the dose of 5 u/kg bm in the mild streptozotocin-induced diabetes model (in comparison with Lantus preparation) are shown in Table 2 and FIG. 6 .
[0174] The results describing influence of GKR insulin on glucose concentration in rat blood after single dose one-time administration of doses 2.5 u/kg bm, 5 u/kg bm and 7.5 u/kg bm in severe streptozotocin-induced diabetes model (in comparison with Lantus preparation and control) are shown in Table 3.
[0175] The results presenting influence of GKR insulin on glucose concentration in rat blood after single dose administration of doses 2.5 u/kg bm, 5 u/kg bm and 7.5 u/kg bm in severe streptozotocin-induced diabetes model (in comparison with control) are shown in FIG. 7 .
[0176] The results presenting influence of GKR insulin on glucose concentration in rat blood after single dose administration of 7.5 u/kg bm in severe streptozotocin-induced diabetes model (in comparison with Lantus preparation) are shown in FIG. 8 .
[0177] The results describing glucose concentration in rat blood after multiple dose administrations of 5 u/kg bm of GKR insulin in mild streptozotocin-induced diabetes model (in comparison with Lantus preparation) are shown in Table 4 and FIG. 9 .
[0178] The results describing glucose concentration in rat blood after termination of administrations of 5 u/kg bm of GKR insulin in mild streptozotocin-induced diabetes model (in comparison with Lantus preparation) are shown in Table 5 and FIG. 10 .
[0000]
TABLE 1
Influence of single dose administration of GKR insulin (in the dose of 5 u/kg bm) on glucose concentration
in blood of normoglycaemic rats, in comparison with Gensulin N (isophane recombined human insulin).
Glucose concentration in blood [mg/dl]*
Number of
Tested
Dose
Before
time of determination in hours after administration
animals
preparation
[u/kg bm]
administration
0.5
1
2
4
6
8
10
12
in groups
GKR Insulin
5
87.5 ±
45.3 ±
32.8 ±
26.7 ±
41.2 ±
58.2 ±
60.7 ±
59.6 ±
65.8 ±
10***
1.0
3.64** {circumflex over ( )}{circumflex over ( )}
1.3** {circumflex over ( )}{circumflex over ( )}
3.5**
4.1**
2.0**
2.9**
1.9**
2.7**
Gensulin N
2
87.6 ±
81.2 ±
55.6 ±
39.1 ±
33.8 ±
46.8 ±
51.3 ±
65.3 ±
70.7 ±
10
3.7
4.2
4.3 ##
4.4 ##
5.1 ##
5.4 ##
5.0 ##
3.2 ##
3.5 ##
0.9% NaCl
Volume
91.5 ±
87.0 ±
88.7 ±
88.9 ±
87.4 ±
88.7 ±
93.0 ±
91.3 ±
93.0 ±
10
solution
s.c., 3 ml/
2.0
2.1
1.7
2.0
3.2
2.2
2.0
2.2
2.9
control
300 g bm
Experimental groups n = 10;
*mean values ± SEM;
Statistical significance
**p < 0.01 GKR insulin vs. initial glucose concentration;
## p < 0.01,
# p < 0.05 Gensulin N vs. initial glucose concentration;
{circumflex over ( )}{circumflex over ( )} p < 0.01 GKR insulin 5 u/kg bm vs. Gensulin N 2 u/kg bm.
***Noted death of one animal in the 2 nd hour.
[0000]
TABLE 2
Influence of single dose administration of GKR insulin in a dose of 5 u/kg bm on glucose concentration in blood
of rats with mild streptozotocyn-induced diabetes, compared with Lantus preparation (insulin glargine).
concentration of glucose in rat blood mean value (mg/dl) ± SEM
Test-
fixed
ed
number
hyper-
pre-
of rats
normo-
gly-
time of blood sampling after single dose administration of the preparation
diabetes
para-
dose
in the
gly-
caemy
(hours)
model
tion
s.c.
group
caemy
0
0.5
1
2
4
6
8
10
12
24
36
mild
GKR
5
20
82.5 ±
250.7 ±
115.6 ±
84.1 ±
93.3 ±
106.7 ±
117.0 ±
130.3 ±
142.0 ±
173.4 ±
209.2 ±
218.2 ±
strepto-
u/kg
3.0
22.2
16.1 {circumflex over ( )}{circumflex over ( )}
7.8 {circumflex over ( )}{circumflex over ( )}
4.8 {circumflex over ( )}{circumflex over ( )}
7.2 {circumflex over ( )}{circumflex over ( )}
4.9** {circumflex over ( )}{circumflex over ( )}
6.9 {circumflex over ( )}{circumflex over ( )}
7.9 {circumflex over ( )}{circumflex over ( )}
18.6
20.4
16.8
zotocyn-
Lan-
bm
9
103.6 ±
229.2 ±
135.6 ±
72.6 ±
69.7 ±
77.9 ±
76.8 ±
106.1 ±
128.2 ±
199.8 ±
224.3 ±
228.7 ±
induced -
tus
2.9
32.5
27.1
5.2
8.4
6.8
5.7
6.0
13.1
36.6
28.8
29.7
32 mg/kg
con-
10
9
91.3 ±
236.1 ±
222.2 ±
205.3 ±
207.4 ±
203.4 ±
205.9 ±
212.0 ±
213.6 ±
213.2 ±
214.8 ±
215.7 ±
bm., i.m.)
trol
nl/
5.9
7.7
24.8
21.5
21.8
20.4
21.3
24.1
23.1
25.6
23.0
24.7
200 g
bm
Statistical significance:
**p < 0.01
* p < 0.05 GKR vs. Lantus
{circumflex over ( )}{circumflex over ( )} p < 0.01
{circumflex over ( )} p < 0.05 GKR vs. control
[0000]
TABLE 3
Influence of single dose administration of GKR insulin (in dose of 2.5 u, 5 u and 7.5 u/kg bm) on glucose concentration
in blood of rats with severe streptozotocin-induced diabetes, compared with Lantus preparation (insulin glargine).
glucose concentration in rat blood mean value (mg/dl) ± SEM
Test-
fixed
ed
number
hyper-
pre-
of rats
normo-
gly-
time of blood sampling after single dose administration of the preparation
diabetes
para-
dose
in the
gly-
caemia
(hours)
model
tion
s.c.
group
caemy
0
0.5
1
2
4
6
8
10
12
24
36
severe
GKR
2.5
10
86.3 ±
570.8 ±
251.4 ±
170.2 ±
250.0 ±
377.4 ±
426.0 ±
463.1 ±
524.2 ±
560.1 ±
551.0 ±
576.4 ±
strepto-
u/kg
3.4
20.1
41.2 ** {circumflex over ( )}{circumflex over ( )}
28.8 ** {circumflex over ( )}{circumflex over ( )}
37.8 ** {circumflex over ( )}{circumflex over ( )}
35.0 ** {circumflex over ( )}{circumflex over ( )}
36.9
42.1
45.3
33.0
40.2
22.7
zotocin-
Lan-
bm
10
84.4 ±
596.8 ±
376.5 ±
284.3 ±
134.55 ±
209.1 ±
314.6 ±
415.2 ±
502.6 ±
546.4 ±
537.6 ±
584.0 ±
in-
tus
3.8
3.1
24.3
28.7
22.9
34.4
52.4
40.0
25.5
17.5
23.2
25.8
duced -
GKR
5
11
84.7 ±
585.9 ±
235.3 ±
122.6 ±
119.6 ±
245.2 ±
367.4 ±
421.1 ±
483.5 ±
546.7 ±
594.4 ±
596.0 ±
45 mg/
u/kg
4.0
7.5
32.0 {circumflex over ( )}{circumflex over ( )}
21.1 {circumflex over ( )}{circumflex over ( )}
11.6 {circumflex over ( )}{circumflex over ( )}
26.7 ** {circumflex over ( )}{circumflex over ( )}
29.9 ** {circumflex over ( )}{circumflex over ( )}
33.8 ** {circumflex over ( )}
30.6
40.1
3.8
3.3
kg bm,
Lan-
bm
11
81.6 ±
572.9 ±
302.3 ±
173.4 ±
123.1 ±
131.3 ±
152.5 ±
262.2 ±
426.7 ±
502.6 ±
580.2 ±
594.6 ±
i.m.)
tus
3.2
12.6
42.7
33.7
21.4
10.9
14.6
36.7
39.8
26.5
10.5
3.1
GKR
7.5
10
89.0 ±
573.9 ±
259.1 ±
133.1 ±
109.2 ±
216.1 ±
280.6 ±
350.6 ±
508.7 ±
526.4 ±
571.0 ±
583.0 ±
u/kg
3.4
18.8
14.2 * {circumflex over ( )}{circumflex over ( )}
19.3 {circumflex over ( )}{circumflex over ( )}
11.8 {circumflex over ( )}{circumflex over ( )}
32.6 ** {circumflex over ( )}{circumflex over ( )}
42.3 {circumflex over ( )}{circumflex over ( )}
49.2 {circumflex over ( )}{circumflex over ( )}
34.0 *
27.3
20.4
17.0
Lan-
bm
10
82.4 ±
594.0 ±
335.4 ±
198.3 ±
106.1 ±
105.5 ±
188.7 ±
309.5 ±
402.6 ±
461.6 ±
596.8 ±
599.3 ±
tus
3.5
6.0
28.5
36.7
22.4
16.8
28.7
54.1
49.3
38.4
3.09
0.7
con-
10
9
74 ±
592.1 ±
578.6 ±
594.2 ±
579.2 ±
548.8 ±
526.0 ±
547.3 ±
544.9 ±
575.3 ±
593.3 ±
594.3 ±
trol
μl/
3.6
5.4
10.2
5.4
13.0
23.5
25.5
23.7
14.0
12.4
6.7
2.6
200
g bm
Statistical significance:
** p < 0.01
* p < 0.05 GKR vs. Lantus
{circumflex over ( )}{circumflex over ( )} p < 0.01
{circumflex over ( )} p < 0.05 GKR vs. control
[0000]
TABLE 4
Influence of multiple administrations of GKR insulin at a dose of 5 u/kg bm on glucose concentration in blood
of rats with mild streptozotocin-induced diabetes compared with Lantus preparation (insulin glargine).
number
glucose concentration in blood of the rats, mean value (mg/dl) ± SEM
Tested
of rats
fixed
prepa-
in the
normo-
hyper-
consecutive days of study
ration
group
glycaemia
glycaemia
1
2
3
4
5
6
7
8
9
10
GKR
20
82.5 ±
198.1 ±
155.4 ±
156.8 ±
157.7 ±
148.1 ±
144.1 ±
151.6 ±
156.6 ±
152.9 ±
147.0 ±
152.3 ±
5 u/kg bm
3.0
12.1
7.1 {circumflex over ( )}{circumflex over ( )}
6.2 {circumflex over ( )}{circumflex over ( )}
7.4 {circumflex over ( )}{circumflex over ( )}
4.5 ** {circumflex over ( )}{circumflex over ( )}
5.3 {circumflex over ( )}{circumflex over ( )}
5.5 {circumflex over ( )}{circumflex over ( )}
6.0 {circumflex over ( )}{circumflex over ( )}
5.7 {circumflex over ( )}{circumflex over ( )}
3.2 {circumflex over ( )}{circumflex over ( )}
3.8 {circumflex over ( )}{circumflex over ( )}
Lantus
9
103.6 ±
228.9 ±
136.3 ±
147.0 ±
173.7 ±
184.9 ±
163.7 ±
171.4 ±
175.8 ±
168.4 ±
142.9 ±
160.4 ±
5 u/kg bm.
2.9
30.7
18.1
9.0
10.4
12.7
11.2
10.4
8.8
15.7
20.3
14.4
control
5
88.8 ±
243.4 ±
229.4 ±
232.6 ±
227.0 ±
254.4 ±
257.0 ±
247.0 ±
258.0 ±
257.0 ±
259.8 ±
252.0 ±
10 nl/
9.4
4.7
13.3
10.6
9.9
9.1
8.2
32.7
6.7
7.9
12.4
6.7
200 g bm
number
glucose concentration in blood of the rats, mean value (mg/dl) ± SEM
Tested
of rats
fixed
prepa-
in the
normo-
hyper-
consecutive days of study
ration
group
glycaemia
glycaemia
11
12
13
14
15
16
17
18
19
20
21
GKR
20
82.5 ±
198.1 ±
152.6 ±
153.6 ±
149.7 ±
151.5±
151.1 ±
149.0 ±
142.7 ±
143.0 ±
149.7 ±
149.9 ±
149.2 ±
5 u/kg bm.
3.0
12.1
2.3 {circumflex over ( )}{circumflex over ( )}
2.9 {circumflex over ( )}{circumflex over ( )}
3.1 {circumflex over ( )}{circumflex over ( )}
3.3 {circumflex over ( )}{circumflex over ( )}
3.4 {circumflex over ( )}{circumflex over ( )}
5.6 {circumflex over ( )}{circumflex over ( )}
3.2 ** {circumflex over ( )}{circumflex over ( )}
4.9 {circumflex over ( )}{circumflex over ( )}
4.7 {circumflex over ( )}
4.3 {circumflex over ( )}{circumflex over ( )}
4.2 * {circumflex over ( )}{circumflex over ( )}
Lantus
9
103.6 ±
228.9 ±
164.8 ±
170.6 ±
161.6 ±
144.0 ±
124.9 ±
156.7 ±
191.3 ±
141.0 ±
172.1 ±
145.7 ±
132.2 ±
5 u/kg bm.
2.9
30.7
13.9
19.3
15.6
18.3
14.7
7.5
19.1
11.4
33.1
15.1
8.9
control
5
88.8 ±
243.4 ±
248.4 ±
255.0 ±
260.0 ±
252.0 ±
249.6 ±
256.2 ±
255.0 ±
259.4 ±
233.6 ±
270.2 ±
268.8 ±
10 nl/
9.4
4.7
8.4
5.5
11.7
14.9
20.4
8.8
19.4
16.7
11.4
11.0
3.7
200 g bm
Statistical significance:
** p < 0.01
* p < 0.05 GKR vs. Lantus
{circumflex over ( )}{circumflex over ( )} p < 0.01
{circumflex over ( )} p < 0.05 GKR vs. control
[0000]
TABLE 5
Glucose concentration in the period after termination of administration of GKR insulin in the dose of 5 u/kg
bm in the model of mild streptozotocin-induced, in comparison with Lantus preparation (insulin glargine).
glucose concentration in rat blood, mean value (mg/dl)
Tested
fixed
in the last day of
days after termination of administration of tested preparations
preparation
normoglycaemia
hyperglycaemia
administration
1
2
3
5
8
11
GKR 5 u/kg bm
86.1 ±
214.4 ±
148.3 ±
146.4 ±
136.0 ±
137.4 ±
132.8 ±
123.2 ±
126.4 ±
3.7
24.3
8.5
9.4
7.8
6.6
3.1
3.1
3.5
Lantus 5 u/kg bm
103.3 ±
254.0 ±
141.0 ±
282.3 ±
277.7 ±
235.0 ±
158.7 ±
195.3 ±
222.3 ±
1.2
67.8
18.2
58.2
72.6
89.7
40.3
63.1
86.4
EXAMPLE 28
Determination of GR Insulin Activity in Animals With Experimental Diabetes
[0179] Hypoglycaemic activity of GR insulin has been confirmed in a moderate streptozotocin-induced dabetes in rats.
[0180] Activity of GR insulin after administration of single doses −5 u or 10 u/kg bm has been determined to be fast and strong. Beginning of activity occurs already after 30 minutes after administration of the preparation and remains at the same level up to 2 hours, and subsequently weakens until reaching initial levels in 24 th -36 th hour.
[0181] Results describing influence of GR insulin preparation on glucose concentration in blood of rats after single dose administration of 5 u and 10 u/kg bm doses in a model of moderate streptozotocin-induced diabetes (in comparison with Lantus preparation) are shown in Table 6. A plot of glucose concentration/time changes after administration of 5 u/kg bm of GR insulin is shown in FIG. 11 .
EXAMPLE 29
Determination of GEKR Insulin Activity in Animals With Experimental Diabetes
[0182] Hypoglycaemic activity of GEKR insulin analogue has been confirmed in a preliminary study on a rat streptozotocin-induced diabetes of moderate course.
[0183] After single administration of GEKR insulin in a dose of 10u/kg bm there was observed very quick (already after 0.5 hour), strong activity reducing glucose concentration in animals' blood. This activity peaked already one hour after administration of the preparation and slowly decreases, still causing significant decrease of glucose level in comparison to initial values up to 12 hours after administration. This research was conducted in comparison with Levemir preparation, insulin analogue of prolonged activity (insulin detemir).
[0184] Results describing influence of GEKR insulin on glucose concentration in rat blood after single dose administration of 10 u/kg bm in a moderate streptozotocin-induced model of diabetes, in comparison with preparation Levemir, are shown in Table 7, and a plot of glucose concentration change as a function of time after administration 10 u/kg bm of GEKR insulin in FIG. 12 .
[0000]
TABLE 6
Influence of single dose administration of GR insulin (doses of 5 u/kg bm and 10 u/kg bm) on glucose concentration in
blood of rats with moderate streptozotocin-induced diabetes in comparison with Lantus preparation (insulin glargine).
glucose concentration in rat blood mean (mg/dl) ± SEM
Test-
fixed
ed
number
hyper-
pre-
of rats
normo-
gly-
time of blood sample acquisiton after single dose preparation administration
diabetes
para-
dose
in the
gly-
caemia
(hours)
model
tion
s.c.
group
caemia
0
0.5
1
2
4
6
8
10
12
24
36
moderate
GR
5.0
15
80.6 ±
507.4 ±
113.9 ±
98.5 ±
92.5 ±
160.3 ±
198.1 ±
268.7 ±
294.9 ±
353.0 ±
406.9 ±
498.4 ±
strepto-
u/kg
2.4
22.9
10.8**
7.6
6.7
18.3
22.6*
29.3
29.4
28.5
28.3**
26.8
zotocin-
Lan-
bm
5
83.0 ±
600.0 ±
324.8 ±
136.6 ±
102.2 ±
97.2 ±
94.8 ±
157.6 ±
266.6 ±
401.4 ±
600.0 ±
594.0 ±
induced -
tus
4.3
0.0
35.3
27.0
20.4
11.2
5.3
26.7
60.5
60.4
0.0
5.5
40 mg/kg
GR
10
15
84.9 ±
498.7 ±
96.1 ±
85.7 ±
77.0 ±
151.5 ±
168.3 ±
200.3 ±
248.9 ±
326.1 ±
389.3 ±
431.6 ±
bm i.m.)
u/kg
3.7
25.4
8.1**
4.4**
3.5
14.9
21.0
26.2*
30.6
27.9
27.6
24.4
Lan-
bm
6
77.8 ±
550.2 ±
247.8 ±
134.0 ±
75.0 ±
109.3 ±
94.7 ±
103.7 ±
148.8 ±
223.3 ±
389.2 ±
453.7 ±
tus
2.3
33.9
25.6
21.8
8.1
16.0
20.0
20.9
20.4
42.2
17.8
28.3
con-
10
6
80.5 ±
509.5 ±
527.2 ±
532.0 ±
495.5 ±
463.5 ±
497.2 ±
452.8 ±
491.7 ±
520.3 ±
503.7 ±
507.7 ±
trol
μl/
2.9
40.6
32.5
30.9
26.8
26.9
23.6
31.8
27.8
31.2
35.5
35.3
200
g bm
Statistical significance:
**p < 0.01
*p < 0.05 GR vs. Lantus
[0000]
TABLE 7
Influence of single dose administration of GEKR insulin (in a dose of 10 u/kg bm) on glucose concentration
in blood of rats with moderate diabetes, in comparison with Levemir preparation (insulin detemir).
Concentration of glucose in rat blood mean value (mg/dl) ± SEM
Tested
Time of blood sampling after single dose administration
preparation
fixed
(hours)
diabetes model
and dose s.c.
normoglycaemia
hyperglycaemia
0.5
1
4
6
8
12
moderate
GEKR
90.5 ±
469.5 ±
218.0 ±
109.3 ±
143.7 ±
—
242.3 ±
329.3 ±
streptozotocin-
10 u/kg bm
6.4
65.8
19.7
10.1
22.4
59.2
155.3
induced -
Levemir
98.5 ±
502.5 ±
—
—
—
142.3 ±
—
384.0 ±
40 mg/kg bm, i.m.)
10 u/kg bm
3.5
26.2
22.3
38.7 | New biosynthetic analogues of recombined human insulin of prolonged therapeutical activity, which can find place in prophylactic and treatment of diabetes. | 2 |
BACKGROUND OF THE INVENTION
(i) Field of the Invention
The present invention relates to a voice mail system, particularly to a voice mail system in which terminals are connected via a radio communication network to a server.
(ii) Description of the Related Art
Recently, in a local area network (LAN) or a wide area network (WAN) which is constituted of terminals and a server connected to a network, text electronic mails exchanged between the terminals via the server have been prevailing. Moreover, a document preparation system has been proposed in which the increasing number of electronic mails are efficiently edited and displayed on a display device.
For example, Japanese Patent Application Laid-open No. 245352/1989 discloses a document preparation system which is provided with a server for classifying document preparation data for each terminal and accumulating the data in a storage area to effectively use a kanji dictionary or another resource usable in common and terminals each having a function of reading and editing the data accumulated in the storage area of the server. Moreover, Japanese Patent Application Laid-open No. 240748/1990 discloses an information processing device in which so as to effectively use a data accumulation resource, information data is managed in one way by a server so that the information data in the server can be edited by plural terminals. Furthermore, a data compression system or the like has been recently put to practical use in which a data accumulation resource, a communication resource and the like are effectively used by decreasing redundancy of information data.
In a conventional text electronic mail system, in a case where comments on a received mail are returned or transferred, the comments are attached as reference data partially or entirely to the received mail and returned or transferred.
However, when the returning/transferring is performed by using a radio communication which is generally narrower in communication band and more expensive as compared with a cable communication, the quantity of the applied reference data has an influence on communication cost, but there is only a small necessity to intentionally reduce the applied quantity of the reference data for the saving of the communication cost because the quantity of the text information is small.
Here, it is supposed that the returning/transferring is performed in a voice mail system in which plural terminals are connected via a radio communication network or the like to a server. It is clear that in order to answer or indicate a complicated message, the reference to a received voice is more important rather than the reference to the text document mail. However, even if the quantity of voice data sufficient for providing a meaning as a reference voice is compressed with a compression technique, the quantity of data to be transmitted is remarkably large. This means that the application of the reference data to the communication resource is a large burden on the communication cost in the voice mail system as compared with the text electronic mail system in which comments can be easily attached or inserted to the received text mail and sent. It is especially a large burden in the voice mail system using the radio communication which is largely restricted as the communication resource. This suggests that there should be a similar problem about family data, image data or another information which needs to form a mass of data with a certain size to have a meaning.
Furthermore, in the conventional voice mail system, a voice mail can be transmitted only in one direction, and a bi-directional voice mail cannot be transmitted/received among plural terminals.
SUMMARY OF THE INVENTION
Wherefore, an object of the invention is to provide a voice mail system in which self voice data can be easily attached and returned by eliminating redundant voice data as much as possible.
Another object is to provide a voice mail system in which a bi-directional voice mail communication can be realized.
To attain these and other objects, the present invention provides a voice mail system in which a server is connected via a communication medium to at least one terminal and the server manages a memory for storing plural voice mail data as identifiable files in a memory region allocated to each terminal.
The server has transmission means for, when a mail request is received via the communication medium from the terminal, reading the voice mail data from a memory region of the memory allocated to a transmitting-end terminal to transmit the data to the transmitting-end terminal; and memory control means for, when a mail editing signal is received, inserting or attaching and re-accumulating the voice mail data in the mail editing signal to a position indicated by the mail editing signal of the memory region of the memory allocated to the transmitting-end terminal.
Each terminal has mail request transmission means for transmitting the mail request via the communication medium to the server; memory means for, when the voice mail data is received via the communication medium from the server, storing the received voice mail data; conversion means for converting the received voice mail data read from the memory means into a voice to output the voice; input means for entering optional voice mail data; and signal transmission means for, when a voice mail is inputted by the input means while the voice is outputted from the conversion means, generating a signal including a position of the memory means from which the received voice mail data is read at the time of input, data of the inputted voice mail and a self terminal identification number as the mail editing signal to transmit the mail editing signal via the communication medium to the server.
In the invention, the server manages the memory for storing plural voice mail data as the identifiable files in the memory region allocated to each terminal, and the terminal transmits the mail request signal to the server or generates the voice mail data self-inserted to an optional position of the received voice mail together with the received voice mail data reading position of the memory means corresponding to the inserted position and the self terminal identification number as the mail editing signal to transmit the mail editing signal via the communication medium to the server. Therefore, even when the terminal transmits the received voice mail with a self voice mail added thereto to the server, the voice mail received from the server does not need to be transmitted to the server again, and the voice mail data generated by the terminal can only be transmitted as the mail editing signal to the server.
Moreover, the server of the invention may further has means for, when the mail editing signal is received, after the memory control means inserts or applies and re-accumulates the voice mail data in the mail editing signal to the position indicated by the mail editing signal of the memory region of the memory allocated to the transmitting-end terminal, transmitting the re-accumulated voice mail data of the memory region to a terminal of a transmission destination in the mail editing signal.
In the invention, a first terminal having transmitted the mail editing signal can transmit via the server to a second terminal the voice mail data which is constituted by inserting or attaching the voice mail data entered by the first terminal to the voice mail data addressed to the first terminal. Therefore, when the second terminal receives and regenerates the voice mail data, a voice of a first person of the voice mail received by the first terminal with a voice of a second person or user of the first terminal added thereto is heard. Specifically, a conversation between the first person and the second person is made. At this time, the voice information in the mail editing signal transmitted by the first terminal to the server is only the voice information of the second person, and the voice information of the first person is not transmitted. Therefore, in the invention, a double or more efficient conversational communication is permitted as the case may be, as compared with a case where the voice information of the first and second persons are added and communicated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing a constitution of a voice mail system according to the invention;
FIG. 2 is a diagrammatic view showing an example of data stored in a memory region of a memory allocated to a terminal 13 shown in FIG. 1;
FIG. 3 is a diagrammatic view showing an example of data stored in a memory region of a memory allocated to a terminal 14 shown in FIG. 1;
FIG. 4 is a block diagram showing a constitution of the terminal of FIG. 1;
FIG. 5A is a sequence diagram showing operation of the system of FIG. 1;
FIGS. 5B, 5C and 5D are diagrams showing formats of signals a, b and c of FIG. 5A, respectively;
FIG. 6 is a diagrammatic view showing an example of data stored in a received data area of a memory 47 of FIG. 4; and
FIG. 7 is a diagrammatic view showing an example of data stored in a transmitted data area of the memory 47 of FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram of a voice mail system according to an embodiment of the invention. As shown in FIG. 1, the voice mail system of the invention is constituted of a server 11 for managing a memory 15, terminals 13 and 14 and a radio communication network 12 for connecting the server 11 to the terminals 13 and 14.
The memory 15 is a memory device for storing plural voice mail data as identifiable files in a memory region allocated to each terminal, e.g., a magnetic disc device, and stores a voice mail in, for example, a format shown in FIG. 2. In FIG. 2, a terminal identification number MS#3 is stored in a top address (address 0 in FIG. 2) of the memory region allocated to the terminal 13, and a mail identification number M1 or M2 of a mail is stored in a top of a memory region (every ten addresses in FIG. 2) allocated to each mail. Additionally, in FIG. 2, ml(1), ml(2), ml(3) . . . denote voice data of a first mail (voice mail data), and m2(1), m2(2) . . . denote voice mail data of a second mail.
FIG. 4 is a block diagram showing an embodiment of the terminal 13 or 14 of FIG. 1. Each terminal is constituted of a radio section TRX 41, a voice code decoder CODEC 42, a loudspeaker SP 43, a microphone MIC 44, a central processing unit CPU 45, an operation switch SW 46, a memory 47 and a display section DISP 48.
Operation of the terminal of FIG. 4 will be described.
The CPU 45 performs a radio communication with the server 11 through the radio section 41. At this time, transmitted/received voice mail data is temporarily stored in the memory 47. When the CPU 45 reads the voice mail data from the memory 47, the voice mail data is successively read from the memory 47 and sent to CODEC 42. The CODEC 42 decodes and converts the voice mail data as a digital signal to an analog voice signal to supply the signal to the loudspeaker 43.
Moreover, in a case where the voice mail data is transmitted, after a voice signal which is obtained by acoustic-electric converting a voice transmitted by the microphone 44 is coded to a digital signal or voice mail data by CODEC 42, the voice mail data is successively accumulated to an address of the memory 47 designated by CPU 45. Subsequently, the voice mail data temporarily accumulated in the memory 47 is sent to the radio section 41 for radio transmission to the server 11.
The operation switch 46 is connected to CPU 45, and is operated by a person to instruct CPU 45 to fetch a mail, record a voice, transmit a mail or otherwise. The display section 48 displays results of operation of CPU 45 by means of the operation switch 46 or the like by the control of CPU 45.
Operation of the embodiment shown in FIG. 1 will be described. When the terminal 13 fetches the mail from the server 11, first mail reception information notified beforehand by the server 11 is displayed on the display section 48, and the identification number of the mail to be fetched is selected and determined with the operation switch 46 to request for mail selecting/reading. Then, as shown in a sequence diagram of FIG. 5A, the terminal 13 radio-transmits a signal a via the radio communication network 12 to the server 11. As shown in FIG. 5B, the signal a has a format which is obtained by synthesizing a terminal identification number 51 indicative of a transmitting end (the identification number MS#3 of the terminal 13), a control code 52 indicative of a mail request and a mail identification number 53 (M1) selected by the operation switch 46 in a time series, and is generated by CPU 45.
When receiving the signal a, the server 11 decodes the signal a and reads the voice mail data subsequent to the mail identification number M1 in the memory region allocated to the terminal identification number MS#3 of the memory 15. As shown in FIG. 2, the voice mail data subsequent to the mail identification number M1 of the memory region allocated to the terminal identification number MS#3 of the memory 15 are ml(1), ml(2) and ml(3) stored in addresses 2 to 4. Subsequently, as shown in FIG. 5A, the server 11 radio-transmits a signal b having the voice mail data ml(1), ml(2) and ml(3) via the radio communication network 12 to the terminal 13.
As shown in FIG. 5C, the signal b has a format which is obtained by synthesizing a terminal identification number 54 indicative of a transmission destination (the identification number MS#3 of the terminal 13), a control code 55 indicative of a mail reading, a received mail identification number 56 (M1) and voice mail data 57 (ml(1), ml(2) and ml(3) described above) in a time series.
The CPU 45 of the terminal 13 identifies the received signal b as a signal addressed to itself based on the terminal identification number 54 of the signal b, and stores the mail identification number M1 and the voice mail data ml(1) to ml(3) subsequent to the control code 55 indicative of the mail reading in the signal b into and successively from a predetermined address 1 of the memory 47 shown in FIG. 6. Thereafter, CPU 45 reads the voice mail data ml(1) to ml(3) from the memory 47 in address sequence to supply the data to CODEC 42. The voice mail data ml(1) to ml(3) are decoded by CODEC 42, and emitted as a voice mail from the loudspeaker 43.
A case where while a user of the terminal 13 is listening to the voice mail, regeneration of the voice mail is temporarily halted to record a self voice as a reply to be returned will be described. For example, at a point when the terminal 13 emits the voice mail data ml(1) in the address 2 of the memory 47 as a sound from the loudspeaker 43, the user starts pushing down the operation switch 46. In this case, CPU 45 of the terminal 13 secures a transmission memory area in the memory 47 and, as shown in FIG. 7, stores the mail identification number M1 into a top of the transmission memory area and a reading address AD2 (address indicative of a position relative to the address 1 storing the mail identification number M1 shown in FIG. 6) of the memory 47 at the time of the pushing of the operation switch 46 into the subsequent address.
Subsequently, successively from the address next to the address storing the address AD2 of the transmission memory area of the memory 47, CPU 45 stores a voice signal which is entered via the microphone 44 by the user and digitized as the voice mail data by CODEC 42, until the pushing of the operation switch 46 is released. Here, the user of the terminal 13 stores the voice mail data diametrically shown by (A) in FIG. 7A into an address next to the address storing the address AD2 of the transmission memory area of the memory 47.
Subsequently, if the user releases the pushed operation switch 46, CPU 45 resumes the halted reading of the voice mail data stored in the memory 47 from the address 3 next to the interrupted address 2. Thereby, as shown in FIG. 6, the voice mail data is read in sequence: ml(2); then ml(3). Additionally, in a case where the operation switch 46 is again pushed while the user of the terminal 13 is reading the voice mail data ml(2) or ml(3), another data accumulation area is secured in the transmission memory area shown in FIG. 7, and the voice mail data is accumulated in the same manner as aforementioned.
In a case where the user of the terminal 13 finishes recording his reply to transmit a mail including the received voice mail and his reply to another terminal 14, the user enters an identification number of a transmission destination or MS#4 of the terminal 14 with the operation switch 46. Then, as shown in FIG. 5A, CPU 45 of the terminal 13 radio-transmits a signal c via the radio communication network 12 to the server 11.
As shown in FIG. 5D, the signal c has a format which is obtained by synthesizing a terminal identification number 51 indicative of a transmitting end (the identification number MS#3 of the terminal 13), a control code 58 indicative of a mail editing, a transmission memory area mail identification number 59 (M1 in FIG. 7), a terminal identification number 60 indicative of a transmission destination (the identification number MS#4 of the terminal 14), a reading address number 61 (AD2 in FIG. 7) of the memory 47 at a time when the operation switch 46 is pushed and voice mail data 62 (the aforementioned (A)) in a time series.
The server 11 receives and decodes the signal c, starts reading the voice mail data successively from an address subsequent to the mail identification number M1 of the memory region allocated to the terminal identification number of the memory 15 shown in FIG. 2, stops reading in a position of the address number AD2, and inserts the voice mail data 62, i.e., (A) in the signal c received from the terminal 13. After the insertion of the voice mail data 62 is completed, the reading of the voice mail data is restarted from an address next to the address of the address number AD2 of the memory 15.
In this manner, the server 11 successively accumulates the read data into a memory region of the memory 15 allocated to the terminal identification number MS#4 of the terminal 14. Thereby, in the memory region allocated to the terminal identification number MS#4 of the memory 15, as shown in FIG. 3, the voice mail data (A) is inserted and written between the voice mail data ml(1) and ml(2).
Thereafter, the server 11 radio-transmits via the radio communication network 12 to the terminal 14 a signal having a format which is constituted by synthesizing a terminal identification number indicative of a transmission destination (the identification number MS#4 of the terminal 14), a control code indicative of a mail reading and the mail identification number M1 or voice mail data read from the memory region allocated to the terminal identification number MS#4 of the memory 15 in FIG. 3 in a time series.
When the terminal 14 receives and decodes the signal, the voice mail is received in the same manner as when the signal b of the terminal 13 is received, so that a voice mail of the voice mail data ml(1) to ml(3) received by the terminal 13 can be heard while a voice mail of the voice mail data (A) of the user of the terminal 13 is inserted between voice mails of the voice mail data ml(1) and ml(2).
In practical modes for use, in a case where the voice mail received by the terminal 13 is originally sent from the terminal 14, the voice mail can be used in a conversational format of questions and answers. Alternatively, in a case where the voice mail received by the terminal 13 is not related with the terminal 14, the mail can be used as an indication with comments.
As aforementioned, in the embodiment, since the data stored in the memory 15 managed by the server 11 can be shared for use by the terminals 13 and 14, transmission from the terminals 13 and 14 can be limited only to the information generated in a self station. Therefore, the same information is prevented from passing through the radio communication network 12 many times, and a reply or an indication can be added.
The present invention is not limited to the embodiment described above. For example, only one terminal may be connected to the server, or the server and the terminal may be connected via a communication network using a medium of infrared ray. Furthermore, the operation switch 46 is not limited to a manual switch, and may be a known switch of speech recognition.
As aforementioned, according to the invention, since the server manages the memory for storing plural voice mail data as identifiable files in the memory region allocated to each terminal, even in the case where the voice mail received by the terminal is transmitted to the server by adding self voice mail data, the voice mail received by the server does not need to be sent to the server again. The voice mail data generated by the terminal can only be transmitted as the mail editing signal to the server. Therefore, the same mail data is prevented from being transmitted/received between the server and the same terminal many times. Consequently, a remarkably efficient communication can be realized in a communication network which has a slower transmission rate and is more expensive as compared with a cable network.
Moreover, according to the invention, the first terminal having sent the mail editing signal can transmit via the server to the second terminal the voice mail data which is constituted by inserting or applying the voice mail data entered by the first terminal to the voice mail data addressed to the first terminal. Therefore, a reply or an indication can be added to the voice mail which can be heretofore transmitted only in one direction. A gentle and inventive communication service of "non-real-time conversation" can be realized on a reception side. | When receiving voice mail data from a server 11, a terminal 13 or 14 stores the voice mail data in a memory. Subsequently, the data is read, converted to a voice and outputted. Furthermore, when inputting a voice mail during the output of the voice, the terminal 13 or 14 generates a signal including a voice mail data reading position of the memory at the time of input, data of the inputted voice mail and a self terminal identification number as a mail editing signal to transmit the signal to the server 11. When receiving the mail editing signal, the server 11 inserts or attaches and re-accumulates the voice mail data in the mail editing signal to a position indicated by the mail editing signal of a memory region of a memory 15 allocated to a transmitting-end terminal. | 7 |
RELATED APPLICATIONS
This application is a divisional application of U.S. patent application Ser. No. 10/991,025, filed Nov. 17, 2004, now U.S. Pat. No. 7,565,250, which claims priority from U.S. Provisional Patent Application No. 60/527,389, filed Dec. 6, 2003.
COPYRIGHT NOTICE
Pursuant to 37 C.F.R. 1.71(e), applicants note that this disclosure contains material that is subject to and for which is claimed copyright protection, such as, but not limited to, source code listings, screen shots, user interfaces, user instructions, and any other aspects of this submission for which copyright protection is or may be available in any jurisdiction. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or patent disclosure, as it appears in the records of the Patent and Trademark Office. All other rights are reserved, and all other reproduction, distribution, creation of derivative works based on the contents, public display, and public performance of the application or any part thereof are prohibited by applicable copyright law.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to analysis of data of nucleic acid amplification reactions. More specifically, the invention relates to an information system and method for making determinations regarding chemical and/or biological reactions. The invention also involves an alternate method of quantifying nucleic acids in a sample comprising amplification of a target nucleic acid and analysis of data obtained during the amplification reaction. The invention further involves a diagnostic system and/or kit using real-time nucleic acid amplification including, but not limited to, PCR analysis.
2. Discussion of the Art
In many different industrial, medical, biological, and/or research fields, it is desirable to determine the quantity of a nucleic acid of interest. Some methods of quantifying nucleic acids of interest involve amplifying them and observing a signal proportional to the quantity of amplified products made; other methods involve generating a signal in response to the presence of a target nucleic acid, which signal accumulates over the duration of the amplification reaction. As used herein, nucleic acid amplification reaction refers both to amplification of a portion of the sequence of a target nucleic acid and to amplification and accumulation of a signal indicative of the presence of a target nucleic acid, with the former often being preferred to the latter. The quantification of nucleic acids is made more difficult or less accurate or both because data captured during amplification reactions are often significantly obscured by signals that are not generated in response to the target nucleic acid (i.e., noise). Furthermore, the data captured by many monitoring methods can be subject to variations and lack of reproducibility due to conditions that can change during a reaction or change between different instances of a reaction. In view of the above, there is a need to develop improved means of quantifying a nucleic acid. Where quantification of nucleic acids is enabled by amplification reactions, there is also a need to improve current methods of detecting suspect or invalid amplification reactions. There further remains a need to improve current abilities to distinguish between amplification reactions that do not detect a target nucleic acid (i.e., negative reactions) from weak signals obtained from amplification reactions suffering from low quantities of a target nucleic acid in a sample, a degree of inhibition of the amplification reaction, or other causes. The present invention provides improvements in these areas as is disclosed below.
A non-exhaustive list of references providing background information regarding the present invention follows:
Livak, K. and Schmittgen, T., Analysis of Relative Gene Expression Data Using Real - Time Quantitative PCR and the 22 DDCT Method, METHODS 25: 402-408 (2001) doi:10.1006/meth.2001.1262. Bustin S A, Absolute quantification of mRNA using real - time reverse transcription PCR assays, Journal of Molecular Endocrinology 25: 169-193 (2000). Bustin S A., Quantification of mRNA using real - time reverse transcription PCR: trends and problems, J Mol Endocrinol. 29: 23-29 (2002). While the inventors cannot guarantee that the following website will remain available and do not necessarily endorse any opinions expressed therein, an interested person may wish to refer to the world wide web at www.wzw.turn.de/gene-quantification/index.shtml for useful background information.
The discussion of any works, publications, sales, or activity anywhere in this submission, including in any documents submitted with this application, is not intended to be an admission of any manner that any such work constitutes prior art, unless explicitly stated to the contrary. Similarly, the discussion of any activity, work, or publication herein is not an admission that such activity, work, or publication was known in any particular jurisdiction.
Real-time PCR is an amplification reaction used for the quantification of target nucleic acids in a test sample. Conventionally, skilled artisans typically view the amplification reaction as comprising three distinct phases. First, there is a background or baseline phase, in which the target nucleic acid is being amplified but the signal proportional to the quantity of the target nucleic acid cannot be detected because it is too small to be observed relative to signals independent of the target (sometimes called “background” or “background signal”). Next, there is a logarithmic phase in which the signal grows substantially logarithmically because the signal is substantially proportional to the quantity of target nucleic acid in the amplification reaction and is greater than the background signal. Finally, the growth in the signal slows during a “plateau” phase reflecting less than logarithmic amplification of the target nucleic acid. As is known in the art, the time at which the logarithmic phase crosses a threshold value, which is a value somewhat greater than the value of the background signal, is reproducibly related to the log of the concentration of the target nucleic acid. This prior art method is generically referred to as the C t method, perhaps so named for the Cycle at which the signal crosses the threshold. C t analysis is reasonably reproducible and accurate, but suffers from some drawbacks, which need not be discussed here to understand the present invention.
U.S. Pat. No. 6,303,305 discloses a method of quantification of nucleic acids employing PCR reactions. The method disclosed employs the nth derivative of the growth curve of a fluorescent nucleic acid amplification reaction. This method effectively avoids the need to perform a baseline correction, but provides no reliable method of determining reactive from non-reactive samples, and does not reasonably suggest how to use an nth derivative calculation to assess the validity of the results obtained. In addition, nucleic acid amplification signals resulting from any artifacts in the system (e.g., crosstalk or positive bleedover—defined infra) cannot be distinguished from true positive responses using the methods disclosed therein and can lead to false positive results. However, the first derivative calculation disclosed by U.S. Pat. No. 6,303,305 provides an efficiency related value that is useful in the context of the present invention. The skilled artisan can refer to U.S. Pat. No. 6,303,305 for additional details relating to calculation of a first derivative of a nucleic acid amplification signal growth curve. U.S. Pat. No. 6,303,305 is incorporated by reference only in the United States of America, and other jurisdictions permitting incorporation by reference, to the extent it discloses the calculation of the first derivative of a nucleic acid amplification growth curve. However, U.S. Pat. No. 6,303,305 does not disclose or suggest the uses of this efficiency related value described in this disclosure (below).
Co-owned U.S. Provisional Patent Application No. 60/527,389, filed Dec. 6, 2003, discloses a method for analyzing a nucleic acid amplification reaction in which the log of the signal from an amplification reaction is examined for the maximum gradient or slope. This value, which for any data set corresponds to a point a certain period of time or number of cycles after the initiation of the amplification reaction, is called the MGL of the reaction. The MGL is useful in certain embodiments of the present invention, particularly in those that distinguish qualitatively those samples comprising little target nucleic acid from those samples that do not contain target nucleic acid. U.S. Patent Application No. 60/527,389, filed Dec. 6, 2003 is incorporated herein by reference in its entirety.
SUMMARY OF THE INVENTION
The present invention provides a method for determining whether a sample contains a nucleic acid of interest, for quantifying this nucleic acid, and for assessing the validity or quality of the data used to reach the preceding qualitative and quantitative determinations.
The method of this invention method comprises contacting a sample with amplification or detection reagents or both in order to amplify the nucleic acid (as the term “amplified” is used herein). The amplification reaction generates signals indicative of the quantity of the target nucleic acid present in the sample, which signals are recorded at numerous points during the amplification reaction. The signal can be measured and recorded as a function of time value, or in the alternative, cycle number.
Suitable “efficiency related transforms” viewed or calculated as a function of time are determined for the amplification reaction, and the point in the amplification reaction of the maximum of the efficiency related transform, the magnitude of the maximum of the efficiency related transform, or the width (or similar parameter) of a peak in the plot of the efficiency related transform as a function of time can be used to obtain information about the reaction. This point in the reaction represents the point in time or the amplification cycle at which the maximum of the efficiency related transform occurs. Advantageously, the maximum of the efficiency related transform for a particular reaction, as well as the duration and magnitude of substantial changes in the calculated efficiency related transform, have consistently reproducible relationships to the initial concentration of a target nucleic acid in a sample, to the reliability of the data and information generated by the assay, to the presence or absence of a bona fide target nucleic acid, and to other parameters of the reaction. Advantageously, these relationships hold even in the presence of substantial noise and unpredictable variations in the signal(s) generated by the amplification reaction. As used herein, the term “maximum”, as applied to efficiency related transforms, is intended to include the minimum of the efficiency related transform when the reciprocal of the efficiency related transform is used. One can use the inverse ratio, in which, in the case of a curve, the curve will start at a value of approximately 1 in the baseline region, decrease during the growth region, and return approximately to one in the plateau region. The use of this transform would allow one to use the magnitude and the position of the trough instead of the magnitude and position of the peak for analysis. This transform is implemented in a manner that essentially equivalent to the ratio method in which the maximum of the efficiency related transform for a particular reaction is employed.
In all embodiments, signals from the amplification reaction are measured at intervals of time appropriate for the amplification reaction during the amplification reaction. These signals can be referred to as time-based or periodic measurements, such that every measurement of the signal generated for a particular reaction can be expressed as a function of time. In some embodiments, the amplification reaction is cyclical (e.g., as in PCR). Because cycles often have a substantially uniform duration, it is frequently convenient to substitute a “cycle number” for a time measurement. Accordingly, in some embodiments of the present invention, a region of data identified by one or more methods on an information processing system as described herein can correspond to a cycle number. However, some cyclical amplification reactions have cycles of non-uniform duration. For these amplification reactions, it may be preferable to measure time in non-uniform measures. For example, the theoretical extent of amplification in a PCR reaction having cycles of varying duration will be linked more directly to the number of cycles performed rather than the duration of the reaction. Accordingly, the skilled artisan will readily appreciate that the time-based measurements can easily be scaled to reflect the underlying amplification reaction. As is known in the art, it is often useful to interpolate data and results between cycle numbers, which gives rise to the concept of a fractional cycle number “FCN.” Similarly, in reactions where measurements are based on time, events can be measured in fractional time units.
In further embodiments, the invention advantageously involves a system or method or both for analyzing a reaction sample, such as a PCR reaction sample, that uses a substantial set of available reaction kinetics data to identify a region of interest, rather than using a very limited data set, such as where a reaction curve crosses a threshold.
In certain embodiments, an identified region can be used to determine one or more qualitative results, or quantitative data analysis results, or both. The reaction point of the maximum of the efficiency related transform can be used to determine the concentration of a target nucleic acid in a sample or to determine qualitatively whether any target analyte is present in a test sample. These and other values can be compared with reference quantities in generally the same way that a threshold cycle number (C t ) or fractional threshold cycle number can be used in the prior art.
The reaction point corresponding to the maximum of the efficiency related transform can be understood as indicating or being derived from a cycle number that is located at a relatively consistent point with respect to reaction efficiency, such as at a maximum of reaction efficiency or a region consistently related to a maximum of reaction efficiency or consistently related to some other reaction progression. Different methods can be used to determine a reaction point related to a maximum of reaction efficiency. This value can comprise adjusted FCN values (e.g., FCN MR Adj. and FCN Int. Adj. ), as described below. In certain embodiments of this invention, methods of the invention can determine FCN values for multiple reaction signals, such as a target and/or a control and use those values in determining reaction parameters, including, but not limited to, quantity of target nucleic acid initially present in a sample and the validity of the results generated by an amplification reaction.
The present invention can identify a value indicative of the reaction efficiency (at times, herein, generally referred to as an “efficiency related value” (ERV)) at one or more regions on a signal growth curve. A specific efficiency related value is referred to as a MaxRatio value or MR. MaxRatio refers to one possible method for calculating an efficiency related value as further discussed herein. This is one example of a method for determining an ERV and illustrative examples herein that refer to MR should also be understood to include other suitable methods for determining an efficiency related value, including, but not limited to, the maximum gradient of the log of the growth curve, as described in co-owned U.S. Patent Application No. 60/527,389, filed Dec. 6, 2003, the maximum first derivative of the signal obtained from the amplification reaction (e.g., as disclosed in U.S. Pat. No. 6,303,305), and the maximum difference between two sequential signals obtained from the amplification reaction. Thus, this invention is involved with an analytical method that identifies two values for a reaction curve: (1) one value related to a cycle number or time value and (2) one value indicating an efficiency related value. The invention can use those two values in analysis of reaction data performed using an information-handling system and method of using the system. An example of two such values are FCN and MR specific embodiments discussed below.
This invention is also involved with a method and system that uses two values as discussed above that are determined from a reaction under examination to compare that reaction to one or more criteria data sets. A criteria comparison can be used to determine and/or correct any results and/or quantifications as described herein. Criteria data can be derived by generating pairs of cycle number related values-efficiency related values (e.g., FCN-MR pairs) from multiple calibration reactions of known quantity or known concentration or both.
This invention also involves one or more techniques for performing efficiency analysis of reaction data. This analysis can be used separately from or in conjunction with the cycle number related value-efficiency related value analysis discussed herein. Efficiency analysis can be used to find a region of interest for making a determination about reaction data, such as, for comparison to calibration data sets, in a way similar to C t analysis as understood in the art.
The present invention also provides a method for analyzing a nucleic acid amplification reaction, in which a sample containing a nucleic acid is contacted with amplification agents and placed under suitable amplification conditions to amplify a portion of the nucleic acid in the sample. During the amplification reaction, signals that are proportional to the amount of the target nucleic acid present are periodically measured at a suitable interval. Conveniently, the interval can correspond to the duration of a cycle for those amplification reactions that are cyclical. The signals are then manipulated to determine an efficiency related transform for the amplification reaction. Any suitable efficiency related transform can be used for the invention. Efficiency related transforms preferred in the context of the present invention include the slope of the line, which can be determined by many techniques, including, but not limited to, difference calculations on sequential data points, determining the first derivative of a line fitted to the growth curve of the reaction signal, and determining the gradient, slope, or derivative of the log of the growth curve (i.e., Log (growth curve)). More preferably, the efficiency related transform is the ratio of sequential data points, sometimes referred to herein as the ratio curve. When the efficiency related transform for the reaction is known, a plot of the efficiency related transform as a function of time (preferably expressed in the units used to measure the signal) (or mathematical manipulation yielding information similar to a plot) can be used to identify a peak value. However, a plot is not required. The width of the peak in the selected range of acceptable peak widths can be determined by any suitable technique or method. However, a preferred method for determining the acceptable peak width involves statistically analyzing the degree of variance in peak widths obtained from objectively normal amplification reactions that are very similar to or even identical to the amplification method analyzed by the method of this invention. In the reaction analyzed, an unknown test sample is usually used in place of samples used to characterize the amplification reaction or an analyte assay. If the peak width of the analyzed amplification reaction falls within the prescribed range of acceptable peak widths, the reaction is declared normal; if the peak width of the analyzed amplification reaction does not fall within the prescribed range of acceptable peak widths, the reaction is identified as having provided sub-optimal, aberrant, or otherwise questionable signals. The width of the leading half of the efficiency related transform peak is evaluated. This evaluation is a more forgiving measurement of amplification reaction validity, and therefore may be preferred in some instances, but generally not in all instances.
The invention further involves an information system and/or program able to analyze captured data. Data can be captured as image data from observable features of the data, and the information system can be integrated with other components for capturing, preparing, and/or displaying sample data. Representative examples of systems in which the invention can be employed include, but are not limited to, the BioRad® i-Cycler®, the Stratagene® MX4000®, and the ABI Prism 7000® systems. Similarly, the present invention provides a computer product capable of executing the method of this invention.
Various embodiments of the present invention provide methods and/or systems that can be implemented on a general purpose or special purpose information handling system by means of a suitable programming language, such as Java, C++, C#, Cobol, C, Pascal, Fortran, PL1, LISP, assembly, etc., and any suitable data or formatting specifications, such as HTML, XML, dHTML, TIFF, JPEG, tab-delimited text, binary, etc. For ease of discussion, various computer software commands useful in the context of the present invention are illustrated in MATLAB® commands. The MATLAB software is a linear algebra manipulator and viewer package commercially available from The Mathworks, Natick, Mass. (USA). Of course, in any particular implementation (as in any software development project), numerous implementation-specific decisions can be made to achieve the developer's specific goals, such as compliance with system-related and/or business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a developmental effort might be complex and time-consuming, but would nevertheless be a routine undertaking of software engineering for those of ordinary skill in the art having the benefit of this disclosure.
The invention will be better understood with reference to the following drawings and detailed descriptions. For purposes of clarity, this discussion refers to devices, methods, and concepts in terms of specific examples. However, the invention and aspects thereof may have applications to a variety of types of devices and systems.
Furthermore, it is well known that logic systems and methods such as those described herein can include a variety of different components and different functions in a modular fashion. Different embodiments of the invention can include different combinations of elements and functions and may group various functions as parts of various elements. For purposes of clarity, the invention is described in terms of systems that include many different components and combinations of novel components and known components. No inference should be taken to limit the invention to combinations requiring all of the novel components in any illustrative embodiment of this invention.
As used herein, “the invention” should be understood to include one or more specific embodiments of the invention (unless explicitly indicated to the contrary). Many variations according to the invention will be understood from the teachings herein to those of ordinary skill in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plot of discrete captured reaction data values from 43 readings (e.g., cycles) taken from a nucleic acid amplification reaction that can be used in an analysis method according to embodiments of this invention.
FIG. 2 is a plot illustrating captured reaction data showing target and control data sets that have been normalized according to embodiments of this invention.
FIG. 3 is a plot illustrating reaction data showing target and control data that have been scaled according to embodiments of this invention.
FIG. 4 is a plot illustrating captured reaction data showing target and control data after digital filtering according to embodiments of this invention.
FIG. 5 is a plot illustrating captured reaction data showing target and control data with slope values removed according to embodiments of this invention.
FIG. 6 is a plot illustrating ratio transform of reaction target and control data according to embodiments of this invention.
FIG. 7 is a plot illustrating shifted ratio transform of reaction target and control data according to embodiments of this invention.
FIG. 8 is a plot illustrating interpolated transformed reaction data showing target and control data that have been interpolated according to embodiments of this invention.
FIG. 9 is a plot illustrating interposed reaction data showing identification of the FCN and MR points according to embodiments of this invention.
FIG. 10 is a flow chart for performing a characterization of reaction data according to embodiments of this invention.
FIG. 11 is a plot illustrating methods for determining criteria data according to embodiments of this invention.
FIG. 12 is a plot illustrating two sets of reaction data that illustrate how reaction curves for same concentration initial samples can vary due to different reaction anomalies.
FIG. 13 illustrates peak efficiency calculations for the data sets in FIG. 12 . The figure illustrates the desirability of using an offset efficiency transform according to specific embodiments of the present invention.
FIG. 14 illustrates data for an HIV assay run with eight replicates of known concentration samples at 50, 500, 5,000, 50,000, 500,000 and 5,000,000 copies per mL.
FIG. 15 is a plot illustrating four linear standard curves generated from three-point calibration data using four different cycle number related values (e.g., FCN, FCN2, FCN MR Adj. , and FCN Int. Adj. ) according to embodiments of this invention.
FIG. 16 compares calculated concentrations to known concentrations for the data illustrated in FIG. 14 using the four curves illustrated in FIG. 15 according to embodiments of this invention.
FIG. 17 illustrates results using a one-point calibration according to embodiments of this invention.
FIG. 18 illustrates experimental HBV results using MR analysis with a one-point calibration according to embodiments of this invention.
FIG. 19 illustrates experimental HBV results using MR analysis and FCN MR adj. with a one-point calibration according to embodiments of this invention.
FIG. 20 illustrates experimental HBV results using C t analysis and a one-point calibration according to embodiments of this invention.
FIG. 21 illustrates experimental HIV results using MR analysis and one-point calibration, e.g. using 10 3 and 10 7 copies/mL responses as calibrators, according to embodiments of this invention.
FIG. 22 is a plot illustrating two types of criteria data according to embodiments of this invention wherein the lower horizontal line represents criteria data suitable for differentiating negative reactions from positive reactions.
FIG. 23 is a plot illustrating FCN-MR for HIV data from 50 copies/mL to 5,000,000 copies/mL analyzed by a statistics software package to apply a curve fit to the data and to determine confidence intervals according to embodiments of this invention.
FIG. 24 is a plot illustrating internal control data analyzed by a statistics software package to determine confidence intervals according to embodiments of this invention.
FIG. 25 is a flow chart illustrating a logic analysis tree for assessment of assay validity through analysis of pairs of cycle number related value—efficiency related value for both the internal control and the target amplification reactions according to embodiments of this invention.
FIG. 26 is a flow chart illustrating a logic analysis tree for reporting target results with validity criteria assessment using the pairs of cycle number related value—efficiency related value according to embodiments of this invention.
FIG. 27 illustrates the calculation of peak width measurements according to embodiments of this invention.
FIG. 28 illustrates experimental HIV results using the full peak width measurement according to embodiments of this invention.
FIG. 29 illustrates experimental HIV results using the full peak width measurement to identify an abnormal response according to embodiments of this invention.
FIG. 30 illustrates an example of a user interface displaying an FCN-MR plot according to embodiments of this invention.
FIG. 31 illustrates an example of a user interface displaying a shifted ratio plot according to embodiments of this invention.
FIG. 32 is a block diagram showing a representative example of a logic device in which various aspects of the present invention may be embodied.
DETAILED DESCRIPTION OF THE INVENTION
As used herein, the expression “efficiency related value” means a value that has a consistent relationship to the efficiency of an amplification reaction. The expression “efficiency related transform” means a mathematical transformation involving the response in an amplification reaction that is used to determine an efficiency related value. The expression “reaction point” means a point during a reaction at which an efficiency related value occurs. The reaction point can be a point in time measured from the beginning of the reaction. Alternatively, the reaction point can be a point that denotes a cycle measured from the beginning of the reaction. The term “derivative” means the slope of a curve at a given point in the curve.
The present invention is directed to the analysis of a sample containing an analyte. The analyte can be a nucleic acid. In the context of the present invention, copies of a portion of the analyte are made (hereinafter “amplified”) in a manner that generates a detectable signal during amplification. The signal is indicative of the progress of the amplification reaction, and preferably is related either to the quantity of analyte and copies of the analyte present in a test sample, or is related to the quantity of the copies of the analyte produced by the reaction. The amplification is preferably configured to allow logarithmic accumulation of the target analyte (e.g., as in a PCR reaction), and in a more preferred embodiment, the amplification is a PCR reaction in which data are collected at regular time intervals and/or at a particular point in each PCR cycle.
Many systems have been developed that are capable of amplifying and detecting nucleic acids. Similarly, many systems employ signal amplification to allow the determination of quantities of nucleic acids that would otherwise be below the limits of detection. The present invention can utilize any of these systems, provided that a signal indicative of the presence of a nucleic acid or of the amplification of copies of the nucleic acid can be measured in a time-dependent or cycle-dependent manner. Some preferred nucleic acid detection systems that are useful in the context of the present invention include, but are not limited to, PCR, LCR, 3SR, NASBA, TMA, and SDA.
Polymerase Chain Reaction (PCR) is well-known in the art and is essentially described in Saiki et al., Science 230; 1350-1354 (1985); Saiki et al., Science 239:487-491 (1988); Livak et al., U.S. Pat. Nos. 5,538,848; 5,723,591; and 5,876,930, and other references. PCR can also be used in conjunction with reverse transcriptase (RT) and/or certain multifunctional DNA polymerases to transform an RNA molecule into a DNA copy, thereby allowing the use of RNA molecules as substrates for PCR amplification by DNA polymerase. Myers et al. Biochem. 30: 7661-7666 (1991)
Ligation chain reactions (LCR) are similar to PCR with the major distinguishing feature that, in LCR, ligation instead of polymerization is used to amplify target sequences. LCR is described inter alia in Backman et al., European Patent 320 308; Landegren et al., Science 241:1077 (1988); Wu et al., Genomics 4:560 (1989). In some advanced forms of LCR, specificity can be increased by providing a gap between the oligonucleotides, which gaps must be filled in by template-dependent polymerization. This can be especially advantageous if all four dNTPs are not needed to fill the gaps between the oligonucleotide probes and all four dNTPS are not supplied in the amplification reagents. Similarly, rolling circle amplification (RCA) is described by Lisby, Mol. Biotechnol. 12(1):75-99 (1999)), Hatch et al., Genet. Anal. 15(2):35-40 (1999) and others, and is useful in the context of the present invention.
Isothermal amplification reactions are also known in the art and useful in the context of the present invention. Examples of isothermal amplification reactions include 3SR as described by Kwoh et al., Proc. Nat. Acad. Sci . (USA) 86: 1173-1177 (1989) and further developed in the art; NASBA as described by Kievits et al., J. Virol. Methods 35:273-286 (1991) and further developed in the art; and Strand Displacement Amplification (SDA) method as initially described by Walker et al., Proc. Nat. Acad. Sci . (USA) 89:392-396 (1992) and U.S. Pat. No. 5,270,184 and further developed in the art.
Thus, many amplification or detection systems requiring only that signal gains indicative of the quantity of a target nucleic acid can be measured in a time-dependent or cycle-dependent manner are useful in the context of the present invention. Other systems having these characteristics are known to the skilled artisan, and even though not discussed above, are useful in the context of the present invention.
Analysis of the data collected from the amplification reaction can provide answers to one or more of the following questions:
(1) Was the target sequence found?
(2) If yes, what was the initial level or quantity of the target sequence?
(3) Is the result correct?
(4) Did the reaction series run correctly?
(5) Was there inhibition of the desired or expected reaction?
(6) Is the sample preparation recovery acceptable?
(7) Is the calibration to any reference data, if used, still valid?
According to some embodiments of this invention, one or more of these questions can be answered by identifying a region of interest (e.g., an FCN) and an efficiency related value (e.g., an MR) of a target and/or internal control reaction. In other embodiments, one or more of these questions can be answered by comparing such values to data sets herein referred to as criteria data, criteria curves, and/or criteria data sets. In additional embodiments, one or more of these questions can be answered by comparing such values obtained for an internal control, e.g., a 2 nd amplification control reaction, in the same reaction mixture as its criteria data. In still further embodiments, one or more of these questions can be answered by comparing such values obtained for the target reaction to such values obtained for an internal control reaction in the same reaction mixture as their respective criteria data.
For clarity, the invention will be illustrated with reference to real-time PCR reactions, which are one class of measuring and monitoring techniques of high interest in automated and manual systems for detecting and quantifying human nucleic acids, animal nucleic acids, plant nucleic acids, and nucleic acids of human, non-human animal, and plant pathogens. Real-time PCR is also well adapted to detection of bio-warfare agents and other living or viral organisms in the environment. Real-time PCR combines amplification of nucleic acid (NA) sequence targets with substantially simultaneous detection of the amplification product. Optionally, detection can be based on fluorescent probes or primers that are quenched or are activated depending on the presence of a target nucleic acid. The intensity of the fluorescence is dependent on the concentration or amount of the target sequence in a sample (assuming, of course, that the quantity of the target is above a minimal detectable limit and is less than any saturation limit). This quench/fluoresce capability of the probe allows for homogeneous assay conditions, i.e., all the reagents for both amplification and detection are added together in a reaction container, e.g., a single well in a multi-well reaction plate. Electronic detection systems, target-capture based systems, and aliquot-analysis systems and techniques are other forms of detection systems useful in the context of the present invention so long as a given system accumulates data indicative of the quantity of target present in a sample during various time points of a target amplification reaction.
In PCR reactions, the quantity of target nucleic acid doubles at each cycle until reagents become limiting or are exhausted, there is significant competition, an inadequate supply of reactants, or other factors that accumulate over the course of a reaction. At times during which a PCR reaction causes doubling (exactly) of the target in a particular cycle, the reaction is said to have an efficiency (e) of 1 (e.g., e=1). After numerous cycles, detectable quantities of the target can be created from very small and initially undetectable quantity of target. Typically, PCR cycling protocols consist of between around 30-50 cycles of amplification, but PCR reactions employing more or fewer cycles are known in the art and useful in the context of the present invention.
In the real-time PCR reactions described below to illustrate the present invention, the reaction mixture includes an appropriate reagent cocktail of oligonucleotide primers, fluorescent dye-labeled oligonucleotide probes capable of being quenched when not bound to a complementary target nucleic acid, amplification enzymes, deoxynucleotide triphosphates (dNTPs), and additional support reagents. Also, a second fluorescent dye-labeled oligonucleotide probe for detection of an amplifiable “control sequence” or “internal control” and a “reference dye”, which optionally may be attached to an oligonucleotide that remains unamplified throughout a reaction series, can be added to the mixture for a real-time PCR reaction. Thus, some real-time PCR systems use a minimum of three fluorescent dyes in each sample or reaction container (e.g., a well). PCR systems using additional fluorescent probe(s) for the detection a second target nucleic acid are known in the art and are useful in the context of the present invention.
Systems that plot and display data for each of one, or possibly more, reactions (e.g., each well in a multi-well plate) are also useful in the context of the present inventions. These systems optionally calculate values representing the fluorescence intensity of the probe as a function of time or cycle number (C N ) or both as a two-dimensional plot (y versus x). Thus, the plotted fluorescence intensity can optionally represent a calculation from multiple dyes (e.g., the probe dye and/or the control dye normalized by the reference dye) and can include subtraction of a calculated background signal. In PCR systems, such a plot is generally referred to as a PCR amplification curve and the data plotted can be referred to as the PCR amplification data.
In PCR, data analysis can be made difficult by a number of factors. Accordingly, various steps can be performed to account for these factors. For example, captured light signals can be analyzed to account for imprecision in the light detection itself. Such imprecision can be caused by errors or difficulties in resolving the fluorescence of an individual dye among a plurality of dyes in mixture of dyes (described below as “bleedover”). Similarly, some amount of signal can be present (e.g., “background signal”) and can increase even when no target is present (e.g., “baseline drift”). Thus, a number of techniques for removing the background signal, preferably including the baseline drift, trend analysis, and normalization are described herein and/or are known in the art. These techniques are useful but are not required in the context of the present invention. (Baseline drift or trending can be caused by many sources, such as, for example, dye instability, lamp instability, temperature fluctuations, optical alignment, sensor stability, or combinations of the foregoing. Because of these factors and other noise factors, automated methods of identifying and correcting the baseline region are prone to errors.)
Typically in PCR, the answers of interest are generally determined from a growth curve, which characteristically starts out as nearly flat during the early reaction cycles when insufficient doubling has occurred to cause a detectable signal, and then rises exponentially until one or more reaction limiting conditions, such as exhaustion of one or more reactants, begins to influence the amplification reaction or the detection process.
A number of methods have been proposed and have been used in research and other settings to analyze PCR-type reaction data. Typically, these methods attempt to detect when the reaction curve has reached a particular point, generally during a period of exponential or near-exponential signal growth (also known as “the log-linear phase”). While not wishing to be bound by any theory, the inventors believe that the earliest point(s) in which the log linear phase can be observed above the baseline or background signal provides the most useful information about the reaction and that the slope of the log-linear phase is a reflection of the amplification efficiency. Some prior art references erroneously suggest that for the slope to be an indicator of real amplification (rather than signal drift), there has to be an inflection point, which is the point on the growth curve where the log-linear phase ends. The inflection point can also represent the greatest rate of change along the growth curve. In some reactions where inhibition occurs, the end of the exponential growth phase may occur before the signal emerges from the background.
In running a PCR analysis, it is generally desired to determine one or more assay results regarding the initial amount/concentration of the target molecules. For discussion purposes, results may be expressed by answers to at least one of four questions:
(1) Was the target molecule present at all in the initial sample (e.g., a positive/negative detection result)? (2) What was the absolute quantity of the initial target present? (3) What is the confidence (e.g., sometimes expressed as a confidence value that the answers to questions 1 or 2 are correct)? (4) What is the relative amount of the target present in two different samples?
A number of methods have been proposed and can be used in research and other settings to answer one or more of these questions.
Data for PCR reactions is often collected one time in each cycle for each dye that is measured (i.e., fluorescence determined) in a reaction. While such data is useful in the context of the present invention, more precise quantification can be carried out by interpolation between the data points acquired at each cycle. In this way, the data can be analyzed to generate “fractional cycle numbers”, and points of interest can be determined to be coincident with a particular cycle number or at a reaction point between any pair of cycle numbers.
One problem with methods that rely on thresholds, particularly in diagnostic settings where it is desirable to fix thresholds, is that theses methods can be susceptible to errors due to the presence of noise factors, particularly systematic noise factors, such as, for example, “crosstalk” and “bleedover”. Crosstalk can generally be understood as occurring when a signal from an assay in one location (such as one well in a multi-well plate) causes an anomaly in a signal in a different, usually adjacent assay location. Bleedover can generally be understood as occurring in situations where more than one signal or data set is detected from the reaction. While detection dyes for a reaction are selected to be largely independent from each other and to have individual fluorescence emission spectra, the emission spectra sometimes overlap such that the emission spectrum from one dye will bleedover into the emission spectrum of a different dye.
Both crosstalk and bleedover can have the effect of either increasing or decreasing the calculated measurement of interest. Furthermore, in both cases, there can be situations where the curve itself can have an anomaly due to either or both of these phenomena. Systematic noise factors such as crosstalk and bleedover can be especially difficult to deal with when performing a baseline correction.
In some systems of the prior art, in order to detect low-level signals for either qualitative results or quantitative results, a low threshold is generally required. However, the use of a low threshold causes discrimination between a false positive signal due to crosstalk and a correct positive signal to be particularly difficult, because either can cause the PCR curve to rise above an amplification threshold, thereby suggesting that a target analyte is present. Positive and negative bleedover can also present problems. Positive bleedover can produce a false-positive results or cause falsely elevated estimates of the initial quantity of target in a sample, while negative bleedover can cause falsely depressed estimates of the initial quantity of target in a sample or falsely indicate the absence of a target in a test sample.
The method or system of this invention can reproducibly identify a region in a reaction curve or data, preferably using an information processing system, which can then be used to provide results based on the amplification reaction data. The invention can identify this region regardless of the base level of the signal, even in the presence of substantial noise. The invention can furthermore identify a value that is representative of efficiency at that region. This value can be used in determining primary results or in adjusting results or in determining confidence values as described herein, or all of the foregoing.
The invention can be illustrated by a specific example, shown below. In this example, an information processing system is used to analyze data representing the growth curve of an amplification reaction. In the amplification, a “peak” is generated by one step in the data analysis. The location of this peak (measured in time units or in cycles from the initiation of the amplification reaction) is referred to as the fractional cycle number (FCN) and the maximum value of the peak is referred to as the ERV (efficiency related value). These values can be used in a method to identify an efficiency related value region and to determine an efficiency related value at this peak. Both of these values can be understood as being derived from a method that analyzes the shape of the reaction curve regardless of the intensity of the amplification signal, which intensity of amplification signal can vary from reaction to reaction and from instrument to instrument, despite starting with identical samples. The reaction curve is a representation of the reaction wherein a signal substantially indicative of the quantity of target in a reaction is plotted as a function of time or, when appropriate, cycle number. The FCN can be understood as being consistently related to a point of maximum growth efficiency of a reaction curve, and the ERV can be understood as being consistently related to the efficiency at that point.
In some embodiments of this invention, analytical methods can optionally, and advantageously, be employed without use of baseline correction. In some systems and methods of this invention, a reference dye is not needed.
The present invention allows objective quantification of the quantity of a target present in a test sample without the need to calculate a subjective and variable threshold or a C t value, as employed in some techniques of the prior art. Furthermore, the invention can use information that is available for determining the degree of inhibition in a reaction by analyzing the shape of the PCR amplification curve, including data that previously has generally been ignored, such as data in cycles after a C t .
General methods for generating and using data pairs determined from reaction curve data will be understood from the examples below. For clarity, these examples refer to a specific set of data and specific functions for analyzing that data, though the invention is not limited to the examples discussed.
Example 1
Captured Data
By way of example, a typical real-time PCR reaction detection system generates a data file that stores the signal generated from one or more detection dyes. FIG. 1 illustrates a plot of captured reaction data that can be used in an analytical method according to the present invention. In this example, one dye signal (DYE 1 ) provides the captured target data, another dye signal (DYE 2 ) provides captured internal control data, and a further dye signal (DYE 3 ) provides optional captured reference data. These data represent data from a single reaction, taken from a standard output file. This particular plot can be understood to represent initial data to which some type of multi-component algorithm has been applied. In this plot, the x-axis provides an indication of cycle number (e.g., 1 to 45) and the y-axis indicates dye intensity detected, in relative fluorescence units. In this figure, the three different capture data sets are illustrated as continuous curves. However, the actual captured data values are generally discrete signal values captured at each cycle number. Thus, an initial data set as illustrated in FIG. 1 may consist of three sets (target, control, and reference) of suitable discrete values (e.g., about 50 values in this case).
Example 2
Normalization
Although optional, normalization can be performed on the captured data in several different ways. One method involves dividing the target and control values at each cycle reading by the corresponding reference dye signal. Alternatively, the divisor can be the average reference value over all cycles or an average over certain cycles. In another alternative embodiment, the divisor can be the average of the target dye or the control dye or the target dye and the control dye over one or more earlier (baseline) cycles, when no amplification signal is detected. Any known normalization method can be employed in a data analysis. The invention can be used with data that has already been normalized by a PCR system. FIG. 2 is a plot of captured reaction data showing target and control data sets that have been normalized according to the present invention. In this example, as a result of the normalization, the y-axis scale represents a pure number. In this case, the number is between about 0 and 9. Other normalization methods are known in the art and can convert this number to between about 0 and 100 or to any other desired range.
Because normalization is optional, the present invention can be used to analyze reaction data without the use of a normalization or reference dye. Alternatively, the target signal or the control signal or both can be used for normalization.
Example 3
Scaling
Scaling is optional but can be performed to make it easier for a human operator to visualize the data. Scaling does not affect analytical results. Scaling can be carried out in addition to normalization, in the absence of normalization, or before or after normalization.
One method of scaling involves dividing each data set value by the average of the values during some early cycles, generally in the baseline region before any positive data signal is detected. In this example, readings 4 through 8 were averaged and normalization was performed first. FIG. 3 is a plot of reaction data showing target and control data that have been scaled. In this example, scaling forces the early values of the target and control to one, and because the early values are less than one, the division forces the later values to slightly larger pure numbers.
Example 4
Digital Filtering
One or more digital filtering methods can be applied to the captured data to “clean up” the signal data sets and to improve the signal to noise ratio. Many different filtering algorithms are known. The present invention can employ a four-pole filter with no zeros. This eliminates the potential for overshoot of the filtered signal. As an example, this can be implemented with the MATLAB function “filtfilt” provided with the MATLAB Signal Processing Toolbox, which both forward and backward filters to eliminate any phase lag (time delays). An example of parameters and MATLAB function call is as follows:
b=0.3164; a=[1.0000-1.0000 0.3750-0.0625 0.0039]; data(:,:,assay)=filtfilt(b,a,data(:,:,assay)); data(:,:,ic)=filtfilt(b,a,data(:,:,ic));
In this example, “b” and “a” contain the filter coefficients. “data(:,:,assay)” and “data(:,:,ic)” contain the captured data that may or may not have been normalized, scaled, or both. In this case, the filtered data is both normalized and scaled. FIG. 4 is a plot of captured reaction data showing target and control data after digital filtering. The values are not changed by the digital filtering, but the data set is “smoothed” somewhat.
Example 5
Slope Removal/Baselining
An optional slope removal method can be used to remove any residual slope that is present in the early baseline signal before any detectable actual signal is produced. This procedure may also be referred to as baselining, but in some embodiments, the offset is not removed, only the slope. According to this invention, for slope removal, both the target (DYE 1 ) and control (DYE 2 ) signals are examined simultaneously. Whichever signal comes up first defines the forward regression point, and the method generally goes back 10 cycles. If 10 cycles back is before cycle 5, then cycle 5 is used as the initial regression point to avoid any earlier signal transients. A linear regression line is calculated using the signal data between these points and the slope of the regression for each dye is subtracted from that dye's signal. In this case, the slope removal is applied to the normalized, scaled, and filtered data discussed above. FIG. 5 is a plot of captured reaction data showing target and control data with slope values removed. In each of these figures, very little slope was present in early cycles; therefore, the slope removal does not substantially affect the captured data values.
Example 6
Transform Calculation
An embodiment of the method of this invention is the MaxRatio method. In this method, the ratio between sequential measurements is calculated, thereby yielding a series of ratios, each of which can be indexed to a time value or cycle number. Many suitable means of calculating these ratios exist, and any suitable means can be used. The simplest way of performing this ratio calculation utilizes the following function:
Ratio ( n ) = s ( n + 1 ) s ( n )
where n represents the cycle number and s(n) represents the signal at cycle n. This calculation provides a curve that starts at approximately 1 in the baseline region of the response, increases to a maximum during the growth region, and returns to approximately 1 in the plateau region. A MATLAB expression that performs this calculation efficiently is the following:
Ratio= s (2:end,:)./ s (1:end-1,:),
where “s” represents the signal response matrix, with each column representing a separate response.
FIG. 6 shows an example of this ratio transform. Because of the intrinsic background fluorescence, the ratio does not reach 2 as would be expected of a PCR reaction if the signal were doubling. Regardless, the magnitude of the peak is independent of multiplicative intensity variations and is proportional to the rate of growth or efficiency at that point. The method of calculating ratios is simple and efficiently calculated. Other equivalent calculations could be made. An example would involve calculating the forward and reverse ratios and then averaging them. On can use the inverse of the ratio, in which case the curve will begin at a value of approximately 1 in the baseline region, decrease in the growth region, and return to a value of approximately 1 in the plateau region. One would then use the magnitude and location of the trough instead of a peak for analysis. This transform can be implemented in a manner essentially equivalent to the ratio method.
Although the MaxRatio algorithm is usable as described, it is convenient to shift the curve by subtracting a constant, e.g., about one (1), from each point. This operation provides a transformation of the original response, which starts near zero in the baseline region, rises to a peak in the growth region of the curve, and returns near zero in the plateau region. This shifted ratio calculation is described by the following function:
Ratio ( n ) = s ( n + 1 ) s ( n ) - 1. FIG. 7 shows the output of this shifted ratio calculation. The reaction point and magnitude of the peak of the shifted ratio curve is then determined. The reaction point (i.e., distance along the x-axis) specifies the FCN value of the MR and the magnitude specifies the efficiency related value MR (Maximum of the Ratio).
Example 7
Interpolation
In order to enhance cycle number resolution, an interpolation can be performed. Many ways of accomplishing this operation are known in the art. One method of interpolating in the context of the invention is cubic spline interpolation, which provides a smooth interpolation, so that even the second derivative of the captured data sets will be continuous. The invention can be used to interpolate the entire data series. The invention can be used to determine a region of interest and then to interpolate only in that region to achieve sub-periodic, or sub-cycle, resolution. An example of a MATLAB command for performing a cubic spline interpolation is as follows:
out=interp1( x ,in, x 2,‘spline’)
where “x” represents the period (or cycle) numbers (1, 2, 3 . . . ), “in” represents the uninterpolated signal at those cycles, “x2” represents the higher resolution period (or cycle) vector (1.00, 1.01, 1.02, . . . ) and “out” represents the interpolated signal that corresponds to the fractional cycles in “x2”.
FIG. 8 is a plot of captured reaction data showing target and control data that have been interpolated to provide function continuity. As a result of an interpolation, the number of values in the data set will generally increase substantially, for example from 43 values to 4201 values.
It should be understood that the steps described above can be performed in different orders, such as, for example, filtering first, followed by baselining before scaling. However, if the interpolation is performed before the ratio calculation, care must be taken to select the appropriate interpolated response values for the ratio calculation. It is important that the interval between ratio values remain the same. Thus, if cycles are used as the period of measurement, and interpolation increases the time resolution to 0.01 cycles, then the shifted ratio at x=2.35 would be R=s(3.35)/s(2.35)−1.
Example 8
Finding Peaks to Determine FCN and ERV (e.g., MR) of Target and Control
Another step is to select peaks in the data series. This operation involves the steps of (1) finding local peaks and (2) selecting from local peaks one or more peaks for further analysis, optionally using criteria data (defined infra).
A peak-finding algorithm identifies where the slope of the curve changes from positive to negative, which represents a local maximum. The algorithm identifies the locations and the magnitude of the peaks. An example of a MATLAB function to do this calculation is as follows:
function [ind,peaks] = findpeaks(y)
% FINDPEAKS Find peaks in real vector.
% ind = findpeaks(y) finds the indices (ind) which are
% local maxima in the sequence y.
% [ind,peaks] = findpeaks(y) returns the value of the
% peaks at these locations, i.e. peaks=y(ind);
y = y(:)′;
switch length(y)
case 0
ind = [ ];
case 1
ind = 1;
otherwise
dy = diff(y);
not_plateau_ind = find(dy~=0);
ind = find( ([dy(not_plateau_ind) 0]<0) &
([0 dy(not_plateau_ind)]>0) );
ind = not_plateau_ind(ind);
end
if nargout > 1
peaks = y(ind);
end
FIG. 9 is a of an efficiency calculation showing identified FCN and MR values of the target and internal control dyes and a criteria curve according to embodiments of the present invention. For the target data, FINDPEAKS located one peak at cycle axis x=19.42 with a magnitude of 0.354. For the internal control data, FINDPEAKS found peaks at: x=2.03, 5.29, 7.67, 12.83, 22.70, 37.86, with respective magnitudes 0.0027, 0.0027, 0.0022, 0.0058, 0.1738, 0.0222.
Example 9
Selecting Peaks to Determine FCN and ERV (e.g., MR) of Target and Control
In the method discussed above, a number of local maximum peaks are often identified for both the target data and the control data. Various methods can be used for selecting which of these local maximum peaks will be used for determining an FCN and ERV.
Typically, and in particular during well-behaved reactions, the highest peak or maximum peak is selected. In many situations, this selection provides the most reproducible reaction point from which to perform further calculations as discussed herein. However, in some situations, a first peak, or first peak above a particular cutoff or after a particular number of cycles is preferable. Thus, in particular examples, a Max Peak or First Peak selection can be employed where Max Peak finds the largest peak in the shifted ratio curve while First Peak finds the first peak that is higher than some selected value.
Once criteria data are determined, these data can also be used to determine which peak to select for an ERV determination during actual operation, particularly for weak or noisy signals.
In FIG. 9 , for example, for the DYE 2 data, the peak-finding algorithm found six local peaks, but the fifth peak was the maximum peak and was also the only one that was above the criteria curve. Thus, in this example, an FCN determined for DYE 2 is 22.70 and the MR determined for DYE 2 is 0.1738.
An information appliance or system apparatus can also be used to perform the methods of this invention. FIG. 10 is a flow chart for performing a reaction data characterization according to embodiments of the present invention. Further details of this general method will be understood from the discussion below.
The analytic methods described herein can be applied to reactions containing either known or unknown target concentrations. In one embodiment, known target nucleic acid concentrations will be included in calibration wells in a reaction carried out in a multi-well reaction plate, and the ERV and value of the reaction point will be used from these known concentration samples to perform quantification. Known concentrations may also be used to develop criteria data as further described herein.
Example 10
Determining Criteria Curve/Criteria Data Sets
In other embodiments, efficiency related values (e.g., MR values) can be plotted as a function of their reaction point values (FCN values) for a number of data sets of known concentration in order to generate a characteristic criteria curve for a particular assay. The criteria curve is characteristic of a particular assay formulation and detection protocol and can be used to reliably determine positive/negative results, to determine whether a particular result should be discarded as unreliable, to determine a confidence measure of a result, or any combination of the foregoing. In general, pairs of reaction data that lie below a criteria curve indicate non-reactive samples, or non-functional reactions, such as reactions encountering significant inhibition.
Criteria data can be used to select which peaks to report or to use in reaction analysis, or both. Criteria data provide an automatic and reliable method for discriminating between negative results (e.g., target not present at all) and results showing low amount of target.
FIG. 11 is a plot in which the MR of six sets of reactions of known concentration (i.e., standards or calibrators) and one set of negative reactions are plotted as a function of the calculated FCN value of the MR value. This plot allows a criteria curve to be selected. A criteria curve, which was described previously, is any curve or line that separates positive results from negative results. The criteria curve is preferably selected so that it is relatively close to and above the negative reaction data (in the x-y space of the plot). In FIG. 11 , pairs of MR-FCN data from a number of samples of known concentrations determined under the same or similar assay conditions are plotted together with pairs of MR-FCN data from samples that do not contain the target of the assay, which samples are also referred to as negatives. Although the negatives should exhibit no amplification response, the analytical method does determine an MR-FCN data pair for these samples. These data for negative samples usually correspond to noise driven maxima on the response output, which is generally a random response. The MR value determined from noise is very low and far removed from the responses from samples of known concentrations. MR-FCN pairs for negative reactions can cluster if there is a systematic noise source, such as bleedover, in which case the MR-FCN pairs may falsely appear to be positive reaction signals. In characterizing the MR-FCN response of true positives versus true negatives, one can identify a clear region of separation between these two sets of data, which is represented by the broken line or curve in FIG. 11 , the criteria curve. In this figure, each circle represents a FCN-MR data pair. In this case, each of the clusters of circles represents multiple responses at known concentrations of the target. There are eight different replicates at six known concentrations within this example. From the right of the plot, for example, these known concentrations can represent concentrations of 50 copies/ml, 5×10 2 copies/ml, 5×10 3 copies/ml, 4×10 4 copies/ml, 5×10 5 copies/ml, and 5×10 6 copies/ml. These criteria data clusters can be used to generate a criteria curve.
Multiple, relatively simple criteria data sets can be used to provide characteristic criteria curves for a number of assays. One useful approach involves taking the mean of the MR values for the set of negative responses and adding to this value a multiple of the standard deviation of the MR values for the negative responses. For the example shown in FIG. 11 , the criteria curve was set to be a horizontal line equal to the mean plus 10 standard deviations of the MR values for the negative responses. The criteria value in this example was calculated to be about 0.026. In some systems, other considerations can make modification of the criteria value (e.g., an FCN-MR value) desirable to account for potential signal anomalies, such as, for example, crosstalk or positive bleedover. Crosstalk can result from signal in a positive well of a multi-well instrument and influence the signal from a different well. As much as 2% crosstalk has been observed in certain instruments. For this reason, the criteria may be increased so as to avoid classifying true negative samples as positive samples. For the assay data represented in FIG. 11 , the highest MR values for positive assays are about 0.50. Two percent of this value is 0.010. Increasing the criteria by 0.010 should eliminate false positives due to crosstalk. Because the highest MR values in this assay only occur with samples of higher concentration that have smaller FCN values, the criteria may be increased only at smaller FCN values, where crosstalk is likely to occur. This modified criteria set can be described by a series of data pairs (X n , Y n ), which describe a multi-element curve. For example, the modified criteria curve shown in FIG. 11 can be specified by the criteria data set:
( X 1 ,Y 1 )=(1,0.036)
( X 2 ,Y 2 )=(20,0.036)
( X 3 ,Y 3 )=(25,0.026)
( X 4 ,Y 4 )=(45,0.026)
As a further example, the criteria curve shown in FIG. 10 can be specified by the criteria data set:
( X 1 ,Y 1 )=(1,0.10)
( X 2 ,Y 2 )=(10,0.10)
( X 3 ,Y 3 )=(20,0.05)
( X 4 ,Y 4 )=(40,0.05)
Criteria curves and/or criteria data sets, including sets having different shapes or more complex shapes or both, can be determined without undue experimentation. The intended use of the PCR application will call for different approaches to establishing criteria lines. The skilled artisan will readily appreciate that when high sensitivity is desired in an assay, a low criteria line is used. For example, if an assay is designed for differentiating sequence variants, such as population consensus sequence (i.e., a “wild type” sequence) versus polymorphic or variant sequences (e.g., a “single nucleotide polymorphism”), then a criteria line of higher value can be used, because the detection of limiting quantities of target nucleic acid is not usually required in the determination of sequence variants.
The particular example shown in FIG. 11 does not exhibit positive bleedover from the internal control (IC) signal response to the assay signal response. If positive IC signal response to assay bleedover were to be present, a similar modification to the criteria could be made. Because the IC signal response should only occur over a narrow range of FCN values, the criteria could be increased only in that limited range.
Generally, as further discussed herein, a FCN-MR response is determined for samples of known concentration across the target concentration range of interest to define the “normal” response. Additional studies in a population of samples that challenge the assay reaction may be run to see how much deterioration in MR is acceptable before the assay performance is compromised. These types of characterization analyses can be used to establish criteria data or sets of criteria data independently of the standard deviation or other characteristics of the noise or baseline observed when samples that do not contain target nucleic acid are treated under amplification conditions.
According to other embodiments of the invention, criteria data also can be determined in ways similar to determining a C t , for C t analysis as has been done in the prior art. A particular assay under design can be performed a number of times to characterize it's typical MR-FCN response. From this typical response, the criteria data set can be defined. However, unlike C t analysis, in FCN-MR, the response is independent of intensity of signal and is easily reproducible, even across instruments of a particular type that produce highly variable results with identical samples.
Example 11
Alternative Region of Interest
It has been empirically found that the FCN value of an efficiency related value as determined above can be advantageously adjusted to provide an even more reproducible quantification value. For example, FIG. 12 is a plot of two sets of reaction data that illustrate how reaction curves for samples having the same initial concentration can vary due to different reaction anomalies. This figure illustrates two responses for samples containing equal quantities of an HIV target nucleic acid. However, in one response, the signal obtained from the reaction falls off early due to an anomaly in the reaction. This fall off can cause a FCN value determined from the maximum of the shifted ratio curve to vary substantially between the two samples, as illustrated in FIG. 13 . However, the figure also shows that the two gradient curves are more substantially similar at early time or cycle number, which is plotted on the x-axis of the graph.
Thus, the invention involves determining an offset from the cycle number of maximum efficiency value (herein referred to as an FCN2 value), which is the location of another point on a reaction curve that can be used for analysis as described herein. In further embodiments, an Efficiency Related Value Threshold (ERVT) or Ratio Threshold (RT) value can be selected and used to determine a cycle number region of interest. An ERVT or RT can be an automatically or empirically determined value for a particular assay. The RT value can be set near to or at a criteria data level that is determined at the latter cycles during assay calibration.
One embodiment of a method of this invention starts at the FCN value on the shifted ratio curve and determines an earlier reaction point where the curve crosses the RT value. This reaction point is reported as an FCN2 value. It is believed that the FCN2 value provides improved linearity in samples having low copy numbers, in contrast with FCN values for certain assays, such as reactions where non-specific product formation reduces the efficiency of product formation in samples having low copy numbers.
FIG. 13 illustrates the desirability of using an offset efficiency value. This figure shows the shifted ratio curves for the responses shown in FIG. 12 and an RT line at 0.03. For this example, the FCN and FCN2 values are shown in Table 1.
TABLE 1
Response
FCN
FCN2
MR
Well 41
28.81
22.85
0.129
Well 42
28.06
22.92
0.097
Difference
0.75
0.07
0.032
In this example, the curve of one response flattens out early and differs in shape from the curve of the other response, and the shifted ratio curve shows a difference. The early flattening can cause the earlier peak. In this example, the FCN2 values are more closely matched than the FCN values. In general, FCN and FCN2 values have been found to be more precise (lower standard deviations) than C t values. While these examples focus on use of the MR, it will be appreciated that other measures of the efficiency of the amplification reaction can be employed in the FCN and FCN2 embodiments of the present invention. Other efficiency related transforms useful in the context of the present invention include, but are not limited to, (a) use of first derivative, (b) use of the differences between sequential periodic data points, and (c) use of the slope or gradient of the log of the growth curve.
Example 12
Quantification Using MR-FCN Analysis
Quantification is often desired in various types of reaction analysis. In PCR reactions, for example, quantification generally refers to an analysis of a reaction to estimate a starting amount or concentration of a target having an unknown concentration. The invention involves methods or systems or both for using an efficiency related value and a cycle number value (e.g., FCN) to perform a quantification. Specifically, the ERV of a test sample is compared to one or more of the ERV of at least one calibrator, preferably at least two calibrators, and, optionally, 3, 4, 5, or 6 calibrators, each of which contains a known quantity of a target nucleic acid.
In further embodiments, quantification can generally be understood as involving one or more calibration data captures and one or more quantification data captures. The calibration data and quantification are related using a quantification relationship or equation.
In calibration, a relationship between captured data, or a value derived from captured data (such as an FCN, FCN2, or MR, or combination of the foregoing), and one or more known starting concentration reactions is used to establish one or more parameters for a quantification equation. These parameters can then be used to determine the starting concentrations of one or more unknown reactions.
Various methods and techniques are known in the art for performing quantification and/or calibration in reaction analysis. For example, in diagnostic PCR settings, it is not uncommon to analyze test samples in a 96-well reaction plate. In each 96-well reaction plate, some wells are dedicated to calibration reactions with samples having known initial concentrations of target. The calibration values determined for these samples can then be used to quantify the samples of unknown concentration in the well.
Two general types of calibration methods are referred to as one-point calibration and standard curve (e.g., multiple points) calibration. Examples of these types are set forth below. Any suitable calibration method, however, can be used in the context of the present invention.
When there is no inhibition or interference, the PCR reaction proceeds with the target sequence showing exponential growth, so that after N cycles of replication, the initial target concentration has been amplified according to the relationship:
Conc N ∝Conc 0 (1+e) N
which can also be expressed as:
Conc 0 ∝ Conc N × 1 ( 1 + e ) N
where Conc N represents the concentration of amplified target after N reaction cycles, Conc 0 represents the initial target concentration before amplification, N represents the cycle number and e represents the efficiency of the target amplification.
Quantitative data analysis is used to analyze real time PCR reaction curves so as to determine Conc 0 to an acceptable degree of accuracy. Previous C t analysis methods attempt to determine a cycle number at a reaction point where the Conc N is the same for all reactions under analysis. The FCN value determined by the methods of the invention provides a good estimate for the cycle number N for an assay in which no significant inhibition or signal degradation over the dynamic range of input target concentrations is demonstrated. The following proportionality relationship between a starting concentration and FCN can be used:
Conc 0 (FCN)∝1/(1+e) FCN
where Conc 0 (FCN) represents the estimate of the initial target concentration determined by using the FCN value as determined by the methods of this invention.
In other words, the lower the starting concentration of target, the higher the FCN value determined for the PCR reaction. This relationship can be used for both calibration data and for quantification data.
This proportionality relationship can also be expressed as an equivalence, such as
Conc 0 (FCN)= K× 1/(1+ e ) FCN
where K represents a calibration proportionality constant.
For calibration data, Conc 0 (FCN) represents a known concentration, such as 500,000 copies of target nucleic acid/mL; the exponent FCN is a FCN cycle number determined as described above; and e represents the efficiency value for a reaction, with e=1 indicating a doubling each cycle. These factors combine to form a relationship to allow for determination of the proportionality constant. Determination of the proportionality constant can only be made if there is a priori knowledge of the efficiency, e, of the amplification reaction. This a priori knowledge enables a one-point calibration. For quantification data, FCN values are determined for reactions involving samples having unknown concentrations of target. The FCN values are then converted to concentration values by use of the above equation. If the efficiency, e, is not known a priori, then a standard curve quantification method can be used. In this case, for calibration data, different samples having different levels of known concentration are amplified, and the FCN values of the samples are determined. These FCN values can be plotted against the log (base 10) of the known concentrations to describe a log (concentration) vs. FCN response. For an assay that demonstrates no significant inhibition or signal degradation over the dynamic range of input target concentrations, this response is typically well-fitted by a linear curve. The following equation describes the form of this standard curve:
Log 10 (Conc 0 (FCN))= m ×FCN+ b
where Log 10 (Conc 0 (FCN)) represents the log (base 10) of the initial target concentration, m represents the slope of the linear standard curve, and b represents the intercept of the linear standard curve.
By using two or more known concentration calibration samples, a linear regression can be applied to determine the slope, m, and intercept, b, of the standard curve. For quantification data, FCN values are determined for reactions involving test samples of unknown concentration, which values are then converted to log (concentration) values by use of the above linear equation. Results can be reported in either log (concentration) or concentration units by the appropriate conversion.
It should be noted that the one-point calibration equation is easily converted to this linear standard curve form:
Conc 0 (FCN)= K× 1/(1+ e ) FCN
Log 10 (Conc 0 (FCN))=−log 10 (1+e)×FCN+log 10 (K). The linear coefficient m can be used to calculate the efficiency of the particular PCR reaction.
Example 13
Quantification Adjustments
When PCR reactions are subjected to inhibition, the resulting real-time PCR signal intensity can be depressed or delayed. The effect of this signal degradation on an efficiency related value such as MR is a reduction in that value. In addition, the effect of signal degradation on the fractional cycle number is generally to identify the FCN at an earlier cycle number than would be expected for the uninhibited reaction. These factors cause the plot of log (concentration) as a function of FCN to be less well described by a linear curve fitting function. Although higher order curve fitting functions can be applied for a standard curve, a linear fit requires fewer calibration levels and is simpler to calculate.
Some of these problems can be addressed in a standard curve analysis by incorporating an ERV or Intensity value into the quantification relationships as discussed above. Thus, the equations above can be rewritten a:
Conc 0 (FCN Intensity Adj )∝Intensity/(1+e) FCN
Conc 0 (FCN MR Adj )∝MR/(1+e) FCN
where Intensity represents the response intensity (above background) at the determined FCN value, MR represents the MR value as described previously. Conc 0 (FCN Intensity Adj ) represents the estimate of the initial concentration of the target determined by using the FCN value adjusted by using the Intensity value and Conc 0 (FCN MR Adj ) represents the estimate of the initial concentration of the target determined by using the FCN value adjusted by using the MR value.
These expressions take advantage of the relationship observed between the intensity at the selected FCN cycle or the MR determined at the selected FCN cycle, or both, and the change to the FCN value in the presence of inhibition, as discussed above. The net effect is that the right hand side of the proportionality expressions above is relatively insensitive to inhibition and other factors that affect the PCR amplification curve, and, therefore, provide significant robustness as expressions for determining the concentration values of the target.
The following discussion further explains the properties and relationships of FCN, FCN IntensityAdj , and FCN MR Adj . Assuming the efficiency is 1, the previous can be simplified to:
Conc 0 (FCN)∝1/2 FCN
Conc 0 (FCN Intensity Adj )∝Intensity/2 FCN
Conc 0 (FCN MR Adj )∝MR/2 FCN
Taking the Log base two of the expressions yields:
Log 2 (Conc 0 (FCN))∝FCN
Log 2 (Conc 0 (FCN Intensity Adj ))∝FCN−Log 2 (Intensity)
Log 2 (Conc 0 (FCN MR Adj ))∝FCN−Log 2 (MR)
From the right sides of the expressions come the values for compensating for intensity or MR to adjust the FCN value by means of the following formulas:
FCN Int. Adj. =FCN−Log 2 (Intensity)
FCN MR. Adj. =FCN−Log 2 (MR).
This calculation then provides quantification by using adjusted FCN values analogous to using FCN values or C t values. It should be noted that the use of these adjusted FCN values provide significant robustness to inhibition and other factors that affect PCR amplification, such as C t values used in determining the concentrations of the target in the unknown samples. The plot of Log (concentration) vs. these adjusted FCN values is generally well fitted by a linear standard curve. Thus, the present invention provides a method for determining the quantity of a target nucleic acid in a sample comprising involving the steps of (a) finding the period of time or cycle number of an amplification reaction corresponding to a maximum of an efficiency related value, preferably of an MR, and (b) adjusting that value by subtracting a logarithm of the Intensity or a logarithm of the MR, and (c) comparing the value obtained to calibration data obtained using the same methodology.
Example 14
Standard Curve Calibration
Development of a standard curve from known concentrations and use thereof for quantification is well known in the art and can be further understood from the following example. In a typical case, a number of calibration reactions (such as in wells in which the initial concentrations are known) are used during each amplification or series of amplifications to perform the calibration operation. One problem that arises with attempting to quantify a target nucleic acid in a sample through a large range of possible initial concentrations is that quantification of lower quantities of target nucleic acid in any particular reaction becomes more difficult. For example, FIG. 14 illustrates data for an assay designed to quantify the amount of HIV in test samples. The reactions were performed with eight replicates of six known concentrations of target nucleic acid, which were 50; 500; 5,000; 50,000; 500,000; and 5,000,000 copies per mL. The assay data show significant signal suppression in reactions where the copy number is low (the curves farthest to the right). While quantity of the four highest concentrations of target nucleic acid (the curve sets to the left) yielded precise results with low coefficients of variability, the two lowest concentrations produced less precise curves. The imprecision caused by the difficulties in quantifying low concentrations of target nucleic acids in assays having a dynamic range of 100,000 to 1 or more can be addressed by the following methods of this invention.
Because calibration runs in a reaction plate are relatively expensive, it is conventional to collect a minimal acceptable number of calibration data sets. For example, in one implementation, the average of two replicates each of the 500; 50,000; and 5,000,000 copy/mL samples are run along with the diagnostic assays, thereby requiring perhaps six wells in a 96 well plate to be used for calibration reactions.
Because the relationship between the cycle numbers and the log of the calibrator concentration is substantially linear, a linear regression can be performed between a log (e.g., log 10 ) of the calibrator concentrations and the cycle number. This regression can easily be performed via the Excel program and other mathematical analysis software. FIG. 15 illustrates four linear standard curves generated from three-point calibration data using four different cycle number related values (e.g., FCN, FCN2, FCN MR Adj. , and FCN Int. Adj. ).
In each of the curve fit equations, the x-axis displays values of the Log 10 [Target] actual or known concentration. Thus, solving for x provides an expression for converting from cycle number related values to Log 10 (Target) calculated concentration of the assay. If the assay response is not linear with Log (Target), a higher order or more complex regression, or a larger number of calibration reactions, or both, can be used. In this example, the following equations were determined:
FCN=−3.0713*Log 10 (Conc 0 )+31.295
FCN2=−3.0637*Log 10 (Conc 0 )+25.006
FCN MR adj =−3.2344*Log 10 (Conc 0 )+33.271
FCN Int. adj =−3.2870*Log 10 (Conc 0 )+32.775
Example 15
Comparing Quantification Using Different Cycle Number Related Values
In order to examine the different characteristics of calibrations using the different cycle number related values described above, quantification can be performed on various samples having known concentrations, and the concentrations calculated compared with the known concentrations. In one example of such a comparison, the standard curves having the parameters generated above were used to carry out quantification of the assay responses shown in FIG. 14 . The mean of the calculated concentrations of the eight replicates at each known concentration was compared to the known concentration value. FIG. 16 compares log 10 of the known concentration values (x-axis) to the means of the log 10 of each of the calculated concentrations for the eight samples at each concentration.
As indicated by FIG. 16 , the 50 copies/mL samples (log (concentration)=1.7) are slightly over-quantified (i.e., higher than the actual concentration) using FCN, while the accuracy for the FCN method (of the MR) at the higher concentrations is very good. FCN2 is more accurate at the lowest concentration, but somewhat under-quantified (i.e., lower than the actual concentration), and exhibit less linearity and accuracy at some higher concentrations. FCN MR Adj. showed very accurate and linear quantification throughout the concentration range. FCN Int. Adj. also showed substantial improvement in accuracy and linearity compared to FCN, except for very slight under-quantification at the lowest concentration. Accordingly, all four methods work well, but some are better than others for particular situations. Therefore, the skilled artisan can easily select an appropriate method for any particular application to obtain excellent results.
Example 16
Quantification Using One-Point Calibration
A one-point calibration can be used for quantification. In this case, two wells at the 50,000 copies/mL concentration (Log(4.7)) were used for calibration. In order to calculate the calibration constant, the following equation is used: K=Conc 0 *2 FCN , where K represents the calibration constant, Conc 0 represents the known concentration of the calibrator, FCN represents the fractional cycle number of the calibrator, and the efficiency of the reaction, e, as described earlier, is assumed to be 1. Similar calibration constants can be generated using the proportionality relationships such as FCN2, FCN MR Adj. and FCN Int. Adj .
In this case, the constant was generated for two wells and the average was used. Once the calibration constant is generated, the concentration for each assay is calculated with the following equation: Conc=K FCN /2 FCN . FIG. 17 illustrates resulting from a one-point calibration.
As can be seen, the FCN results are elevated at the lowest two concentrations and accurate from log(Conc) equals 3.7 and above. FCN2 shows improved accuracy at low concentrations compared to FCN, but under-quantifies at log(Target) equal to 5.7 and 6.7. FCN-MR adjusted shows good linearity over the entire range with slight over-quantification at the two lowest concentrations. FCN-Intensity adjusted also shows good linearity with very slight under-quantification at the lowest two concentrations. Accordingly, each of these embodiments works well and the skilled artisan can readily select from among these options.
As discussed above, an FCN-MR analysis can be used to characterize a particular reaction as positive or negative or to compare the reaction to criteria data, or both. These values can be used to quantify a reaction. A variety of quantification methods can benefit from FCN-MR analysis rather than C t analysis.
In one embodiment, a FCN value, a FCN2 value, or a FCN adjusted value can be used in any way that a C t value has been used in the prior art. Typically, but not necessarily, FCN-adjusted, FCN2-adjusted, or FCN-adjusted analysis can be applied to various sets of calibration data to thereby develop reference data curves or an equation for comparing the result of a reaction in which the concentration of target is unknown to the results of reactions in which the concentration of target is known. Thus, the present invention can be used to develop reference data and to perform a comparison wherein two values (e.g., FCN-MR) are used both for developing reference data and also for making a comparison to that data.
While experiments using the MR method regularly used different preprocessing steps on the captured data set before processing the data set with a ratio function, most of these steps are not required. In particular, experimental results have indicated that scaling, normalization by a reference dye, baselining (both offset and slope correction), and filtering are not required. However, filtering has generally been found to be desirable as it improves performance in the presence of noise. Slope correction (for the baseline region) has also been found to be desirable as it slightly improves discrimination between samples that do not contain target nucleic acid and those that contain very little target nucleic acid or suffer from significant inhibition of the amplification reaction. Generally, however, when FCN Intensity adj is used, it is preferable to use a normalization technique, such as, but not limited to, scaling or normalization to a reference dye.
Example 17
MR Algorithm Applied to HBV Data Using a One-Point Calibration
HBV assays of control solutions ranging from 10 copies/reaction to 10 9 copies/reaction and negatives were processed on an ABI Prism 7000 with six replicates at each concentration. The captured data was processed using only a digital filter. FCN values were then calculated using a MR algorithm as described above. The concentrations were calculated by means of a one-point calibration using the three of the responses at 10 9 copies/reaction as a reference calibrator.
Even without normalization, scaling, or baselining, the resulting quantification was very good, with the exception of an acceptable amount of over-quantification of the 10 copies/reaction and 100 copies/reaction samples (i.e., the Log(Target)=1 and 2 samples). There was a very clear distinction between the negatives and the 10 copies/reaction assays, with no false positives or false negatives. Additional results indicated that when the same data was quantified with C t analysis, the 10 copies/reaction and 100 copies/reaction assays are also slightly over-quantified, and the precision at all concentrations above 10 copies/reaction is better with the MR analysis. In this case, the C t results were normalized, baselined, and calibrated by means of a two-point calibration with three replicates each at concentrations 10 3 and 10 7 copies/reaction.
FIG. 19 illustrates an example of the same HBV data using MR analysis and with FCN MR adj. , correction. Again, the quantification was performed by means of a one-point calibration with three responses at the 10 9 copies/reaction with no normalization, scaling, or baselining. As can be seen, the over-quantification of the low concentrations is significantly reduced, i.e., the quantitative results are significantly improved.
Example 18
MR Algorithm Applied to HIV Data
In this example, HIV assays of control solution were performed at concentrations of negatives, 50 copies/mL, and 100 copies/mL, through 10 6 copies/mL in replicates of six. The responses were processed by means of the MR algorithm using FCN MR Adj. with normalizing and baselining. FIG. 21 illustrates results the example using MR analysis and two-point calibration, e.g., using two replicates of the 10 2 and 10 5 copies/mL responses as calibrators. There was clear differentiation between the negatives and the 50 copies/mL assays with no false positives or false negatives. As can be seen, there is good linearity and precision.
Example 19
Validity Determination Using Target and IC (FCN, MR) Pairs
It has been found that pairs of reaction time or cycle number values and efficiency related values (e.g., pairs of FCN-MR values) can provide valuable information about a nucleic acid amplification reaction, e.g., a PCR reaction, which can be further enhanced by considering data pairs for both the internal control and target amplification reactions. While pairs for a target reaction alone carry important information about reaction efficiency and can be used for comparison with criteria data, additional factors that arise in processing samples or in the samples themselves may be better analyzed by considering control data as well.
For example, in processing specimens for use in PCR or other suitable amplification reactions, the sample can carry various inhibitors into the reaction, which might be detectable through assessment of target data only. However, abnormal recovery of target nucleic acid during sample preparation typically would not be detected by analysis of a single amplification reaction. Furthermore, a target nucleic acid may possess polymorphic sequences that could impair detection of the target nucleic acid, e.g., if a probe is used that binds to a polymorphic region of the sequence. Mismatches caused by the polymorphic sequence in this region would affect the detected signal, and, consequently, the amplification might not appear as abnormal or inhibited using the evaluation of data pairs for a single amplification. Co-analysis of an internal control together with analysis of the target amplification responses can provide accurate quantification of the target nucleic acid in such samples when other methods would typically indicate an invalid reaction.
Thus, pairs of reaction time or cycle number values and efficiency related values can be used together to assess the validity of a given reaction, such as in a given container or well. One could design the internal control (IC) amplification reaction to be comparable in robustness to the target amplification reaction, or slightly less robust. Robustness in this context means the sensitivity of the reaction performance to factors that can affect the PCR processing pathway, such as inhibition that results from sample preparation or the samples themselves, or to variability in transferring of the reaction mixture by pipette, such as transferring inaccurate amounts of amplification reagents by pipette.
Example 20
Multiple Criteria Data Curves
Multiple criteria curves for the pairs of cycle number value—efficiency related value (e.g., FCN-MR pairs) can be developed and can have different uses or levels of importance, particular for use with validity determination. For example, a first criteria curve can be selected so as to be able to discriminate reactive amplification signals from non-reactive responses. A second criteria curve can be selected so as to be more constraining than the first type, so that it would be useful in identifying sample responses that lead to accurate quantification in contrast to those having partial inhibition that might have lower confidence in quantification. FIG. 22 is a plot illustrating two types of criteria data, wherein the lower horizontal line represents criteria data suitable for differentiating negative from reactive reactions. The second set of lines represents criteria data indicating the normal range for the FCN-MR pair responses. These criteria can be used to distinguish high confidence in quantification in contrast to a lower confidence that might be associated with a value outside this range due to partial reaction inhibition.
For example, the first type of criteria data that differentiates reactive and non-reactive amplification reaction can be referred to as “MR criteria data.” These data act as a cutoff threshold—reactive responses will have MR values that exceed the MR criteria data, whereas negative samples will have MR values that will not exceed the criteria value or criterion line. The criteria data is preferably set so that noise in the response signal does not exceed the criteria, nor will such biases as cross-talk or bleed-over.
The second type of criteria data is referred to as the MR normal range. This range would be the range of MR values for a given FCN over which quantification of the sample is accurate. If a signal response is suppressed, the MR value observed will drop. As the MR value decreases due to inhibition, the FCN value can shift to earlier cycles, whereas a threshold based C t might shift to later cycles. The MR normal range would be the range for MR values in a criteria data set for which a chosen value related to a cycle number would provide an accurate quantitative result for the sample when used to determine the concentration of target in the sample from the assay standard curve.
The “MR normal range” can be developed using a Bivariate Fit of the MR by FCN as will be understood in the art. FIG. 23 , for example, shows a FCN-MR plot for HIV data from 50 copies/mL to 5,000,000 copies/mL. The data was analyzed by means of a statistics software package (such as JMP (SAS Institute, Inc.)) to apply a cubic curve fit to the data. This cubic curve fit is represented by the solid line in middle of the figure. The upper and lower dashed curves represent the confidence interval generated using a confidence interval individual analysis option with an alpha level of 0.001. TABLES 2A, 2B, and 2C illustrate sample data input and output related to FIG. 23 .
TABLE 2A
Summary of Fit
RSquare
0.971668
RSquare Adj
0.969737
Root Mean Square Error
0.023918
Mean of Response
0.401317
Observations (or Sum Wgts)
48
Polynomial Fit Degree = 3
MR = 0.6710196-0.0101107 FCN-0.0039387 (FCN-18.3056){circumflex over ( )}2-0.0004202 (FCN-18.3056){circumflex over ( )}3
TABLE 2B
Analysis of Variance
Sum of
Source
DF
Squares
Mean Square
F Ratio
Model
3
0.86331003
0.287770
503.0120
Error
44
0.02517212
0.000572
Prob > F
C. Total
47
0.88848215
<.0001
TABLE 2C Parameter Estimates Term Estimate Std Error t Ratio Prob > |t| Intercept 0.6710196 0.036617 18.33 <.0001 FCN −0.010111 0.002006 −5.04 <.0001 (FCN-18.3056){circumflex over ( )}2 −0.003939 0.000198 −19.92 <.0001 (FCN-18.3056){circumflex over ( )}3 −0.00042 0.000047 −8.93 <.0001
A statistically derived confidence interval, as shown, is a systematic approach to determining which data points represent “normal” responses and should therefore be quantified. Data points lying outside this interval are exceptional and are preferably identified to a human operator by a software program so that further investigation can be made.
In alternative embodiments, such a curve can be simplified in the form of one or more straight-line segments. This simplification can in some cases be performed by a technician viewing the raw data or may be derived from an alpha interval as discussed above.
A similar statistical fit can be performed on the internal control (IC) data. FIG. 24 , for example, shows a plot of MR as a function of FCN for IC data, namely IC data associated with the data shown in FIG. 23 . This data can be used to determine an IC criteria, which, for example, can be a single value that is five standard deviations below the mean of the MR values of the IC or can be a range or box of values, for example, based on the mean±5 standard deviations of the MR and FCN values.
Thus, the present invention also provides a method for analyzing an amplification reaction, the method comprising establishing a “confidence corridor”, which is a range of selected values provided in pairs in which the first value is a maximum efficiency related value (which is preferably the MR), and the second value is a time value or cycle number value at a reaction point (which optionally can be fractional). The method further comprises determining whether a maximum efficiency value occurring at any particular periodic time value or cycle number value at a reaction point (which optionally can be fractional) falls within the selected range. If the value does not, then further investigation, or disregarding the results, is indicated. Any suitable method can be used to establish the selected confidence corridor. Preferred methods include setting the confidence corridor about 1, 2, 3, 5, 10, or any other suitable number of standard deviations from the mean of data obtained from a set of reactions used to characterize the assay. Another suitable method involves modifying the confidence corridor by observing known aberrant or discrepant results and modifying the confidence corridor to exclude a portion of those aberrant or discrepant results in future assays. The use of the confidence corridor of the present invention can be applied to target nucleic acid quantification, analysis of any of standards, calibrators, controls, or to combinations of the foregoing.
Example 21
Validity Analysis
FIG. 25 is a flow chart illustrating a logic analysis tree for assessment of assay validity through analysis of pairs of cycle number (e.g., FCN) minus of ERV (e.g., MR) for both the internal control and the target amplification reactions. FIG. 26 is a flow chart illustrating a logic analysis tree for reporting target results with validity criteria assessment using pairs of cycle number (e.g., FCN) minus ERV (e.g., MR). In the flow charts, FCN is used for clarity of illustration, but as noted elsewhere herein, other methods can be used to generate the reaction point value, for example, C t method, FCN2, FCN MR Adj. or FCN Int. Adj , or other suitable method.
Thus, a validity check can optionally proceed as a series of questions regarding the internal control (IC) and/or target data.
In FIG. 25 , the left-most arrow blocks provide general descriptions of the steps of the method. Details of method(s) can be understood further by considering the following. The method analyzes a cycle number/ERV pair from both a target and control (IC) reaction. Initially, if (1) the IC MR is above the IC MR criteria data, and then if (2) the IC FCN is within the normal range, and further if (3) the IC MR is within the normal range, then reaction validity is confirmed.
As shown in the figure, an invalid result can be further characterized or explained by considering one or more characteristics of the target MR.
FIG. 26 illustrates a method for analyzing the target data for valid reactions to further characterize a valid result as indicating (1) a non-reactive target sample, (2) a target at a concentration of less than the detecting limit of the assay, (3) a target present but with a quantification inhibited, possibly due to sub-type mismatch, or (4) a valid, quantifiable target reaction.
Thus, by combining the analysis based on multiple targets and using both cycle number and efficiency related values, one can distinguish an inhibited sample from a sample that suffered from poor nucleic acid recovery during sample preparation. The analysis makes use of pre-established knowledge of the assay that is contained in the internal control and target criteria data.
Example 22
Validity Determination Using Peak Width
In contrast to the conventional C t analyses in the prior art, which only presents a single value describing an amplification response, an efficiency related value analysis (and preferably an MR analysis) can provide an efficiency related transform curve with data corresponding to the time value or cycle number value of the entire amplification reaction or any portion thereof. It has been discovered that within a specific assay formulation, normal assay responses generate highly reproducible efficiency related transform curves. One characteristic in particular is the width of the peak of the efficiency related transform curve. It has been found that the width of the peak of the efficiency related transform, e.g., as defined by its width at the half maximum height, varies very little even when the magnitude of the fluorescence intensity varies greatly.
Any suitable method can be used to determine the width of the peak of the efficiency related value. FIG. 27 depicts one suitable method for determining the width of an efficiency related value peak. In FIG. 27 , the full peak width is the width in cycles of the peak at it half maximum level. The HIV responses in FIG. 14 show normalized fluorescence for samples of higher concentration at approximately 8, while the normalized fluorescence for the samples of low concentration is as low as about 1. Using the shifted ratio method to calculate an efficiency related transform for each amplification reaction and computing the full peak width provides the results shown in FIG. 28 . Even with an eight-fold change in final fluorescence intensity, the peak widths are surprisingly conserved within a narrow range. Accordingly, the present invention provides amplification reaction validity criteria, wherein an amplification reaction is deemed valid when the width of the peak of an efficiency related value is contained within a selected range characteristic of the amplification reaction. In FIG. 28 , the dashed horizontal lines in bold type represent the mean of the width measurements plus and minus 10 standard deviations. Width measurements that are not within the range of about 5.5 and 8.0 (as shown in FIG. 28 ) are considered invalid or at least suspect. The skilled artisan can readily vary the parameters describing the acceptance interval, depending on the requirements of the particular assay and without undue experimentation.
Peak width can be used to detect an abnormal assay response. The full peak width calculation was applied to the assay data that contained the abnormal response shown in FIG. 12 . The results are presented in FIG. 29 . As can be seen, normal responses for this data set produce full peak widths between about 6 and 9 cycles whereas full peak width of well 42 is 17.42. Accordingly, the amplification reaction of well 42 is abnormal and is disregarded.
The full peak width calculation will be affected by abnormal variations in amplification response that occur both before and after the reaction point value (e.g., the FCN) of the efficiency related value. Abnormal variations that occur after the reaction point value of the efficiency related value are not considered for an assay validity test, because they cannot affect assay quantification by the MR method. This option can readily be achieved using the half peak width calculation illustrated in FIG. 27 or its equivalent. In the illustrated example, only the width in periodic time units from about the half-maximum efficiency related transform up to about the reaction point value of the maximum efficiency related value is used. Of course, other suitable methods for measuring peak widths and half-peak widths are known in the art.
Example 23
Software Embodiments
The systems of this invention can be incorporated into a multiplicity of suitable computer products or information instruments. Some details of a MR software implementation are provided below. Specific user interface descriptions and illustrations are taken to illustrate specific embodiments only and any number of different user interface methods known in the information processing art can be used in systems embodying this invention. The invention can also be used in systems where virtually all of the options described below are preset, calculated, or provided by an information system, and, consequently, provide little or no user interface options. In some cases, details and/or options of a prototype system are described for exemplification purposes; many of these options and/or details may not be relevant or available for a production system.
Furthermore, software embodiments can include various functionalities, such as, for example, processing reactions with one or two target reactions, or one or more internal control reactions, or reference data, or combinations of the foregoing. A software system suitable for use in this invention can provide any number of standard file handling functions such as open, close, printing, saving, etc.
FIG. 30 illustrates a user interface for processing PCR data according to this invention. In this interface, the selection of appropriate dye(s) corresponding to the target assay, internal control, and reference responses are selected from popup lists in the upper left portion of the window. Tabs for selecting different viewing options are positioned in the middle of the window and are arranged horizontally. FIG. 30 shows that the tab displaying the MR-FCN plot has been selected. FIG. 31 illustrates a user interface showing the same data for well 1 , but displaying the shifted ratio curve. Other tabs allow viewing of the raw fluorescence data, normalized fluorescence, and baselined data for all the responses. In addition, a tab allows inspection of each response individually. Fields to the right of the plot show calculated response values such as MR, FCN, C t , and standard deviation in the baseline region. Below these calculated values are radio buttons allowing the user to display either the assay data or the internal control data.
EMBODIMENT IN A PROGRAMMED INFORMATION APPLIANCE
FIG. 32 is a block diagram showing an example of a logic device in which various aspects of the present invention may be embodied. As will be understood from the teachings provided herein, the invention can be implemented in hardware or software or both. In some embodiments, different aspects of the invention can be implemented in either client-side logic or server-side logic. Moreover, the invention or components thereof can be embodied in a fixed media program component containing logic instructions or data, or both, that when loaded into an appropriately configured computing device can cause that device to perform according to the invention. A fixed media component containing logic instructions can be delivered to a viewer on a fixed medium for physically loading into a viewer's computer or a fixed medium containing logic instructions can reside on a remote server that a viewer can access through a communication medium in order to download a program component.
FIG. 32 shows an information instrument or digital device 700 that can be used as a logical apparatus for performing logical operations regarding image display or analysis, or both, as described herein. Such a device can be embodied as a general-purpose computer system or workstation running logical instructions to perform according to various embodiments of the present invention. Such a device can also be customized and/or specialized laboratory or scientific hardware that integrates logic processing into a machine for performing various sample handling operations. In general, the logic processing components of a device according to the present invention are able to read instructions from media 717 or network port 719 , or both. The central processing unit can optionally be connected to server 720 having fixed media 722 . Apparatus 700 can thereafter use those instructions to direct actions or perform analysis as described herein. One type of logical apparatus that can embody the invention is a computer system as illustrated in 700 , containing CPU 707 , optional input devices 709 and 711 , storage media 715 , e.g., disk drives, and optional monitor 705 . Fixed media 717 , or fixed media 722 over port 719 , can be used to program such a system and can represent disk-type optical or magnetic media, magnetic tape, solid state dynamic or static memory, etc. The invention can also be embodied in whole or in part as software recorded on this fixed media. Communication port 719 can also be used to initially receive instructions that are used to program such a system and represents any type of communication connection.
FIG. 32 shows additional components that can be part of a diagnostic system. These components include a viewer or detector 750 or microscope, sample handler 755 , UV or other light source 760 and filters 765 , and a CCD camera or capture device 780 for capturing signal data. These additional components can be components of a single system that includes logic analysis and/or control. These devices may also be essentially stand-alone devices that are in digital communication with an information instrument such as 700 via a network, bus, wireless communication, etc., as will be understood in the art. Components of such a system can have any convenient physical configuration and/or appearance and can be combined into a single integrated system. Thus, the individual components shown in FIG. 42 represent just one example system.
The invention can also be embodied in whole or in part within the circuitry of an application specific integrated circuit (ASIC) or a programmable logic device (PLD). In such a case, the invention can be embodied in a computer understandable descriptor language, which may be used to create an ASIC, or PLD, that operates as described herein.
OTHER EMBODIMENTS
The invention has now been described with reference to specific embodiments. Other embodiments will be apparent to those of skill in the art. In particular, a viewer digital information appliance has generally been illustrated as a computer workstation such as a personal computer. However, the digital computing device is meant to be any information appliance suitable for performing the logic methods of the invention, and could include such devices as a digitally enabled laboratory systems or equipment, digitally enabled television, cell phone, personal digital assistant, etc. Modification within the spirit of the invention will be apparent to those skilled in the art. In addition, various different actions can be used to effect interactions with a system according to specific embodiments of the present invention. For example, a voice command may be spoken by an operator, a key may be depressed by an operator, a button on a client-side scientific device may be depressed by an operator, or selection using any pointing device may be effected by the user.
It is understood that the examples and embodiments described herein are for illustrative purposes and that various modifications or changes in light thereof will be suggested by the teachings herein to persons skilled in the art and are to be included within the spirit and purview of this application and scope of the claims.
All publications, patents, and patent applications cited herein or filed with this application, including any references filed as part of an Information Disclosure Statement, are incorporated by reference in their entirety. | A method and system for determining the quantity of an analyte initially present in a chemical and or biological reaction as well as a computer implemented method and system to automate portions of the analysis comprising mathematical or graphical analysis of an amplification reaction. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a second continuation-in-part of U.S. application Ser. No. 09/967,678, filed on Sep. 28, 2001, to which the inventors claim domestic priority, and which is incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] The present invention generally relates to devices and systems for sheltering livestock and more specifically to a livestock cooling fan which may be used in conjunction with a cooling system which implements programmable evaporative cooling devices to create an environment which protects the health and productivity of the animals.
[0003] It is known in animal agriculture to cool livestock with evaporative cooling by wetting the animal and then drying the animal through mechanical ventilation or via natural ventilation. It is also known to use fans to deliver air cooled by water to an area occupied by livestock. U.S. patent application Ser. No. 09/967,678, filed by the inventors herein, shows how fans may be interconnected or mechanically linked such that the fans oscillate together over a predetermined area for a given time of the day or for a specific set of conditions, where the system is capable of delivering cooling fog. This type of system creates an environment which is healthy for livestock, and may result in higher yields of milk for dairy cows.
[0004] The oscillation of a fan circuit within application Ser. No. 09/967,678 is programmable. The oscillation of a fan circuit can be concentrated in a particular degree range at certain times of the day to increase animal comfort. The speed at which each fan circuit oscillates is programmable through the entire range of oscillation. A faster oscillation speed may be desired in areas prone to wetting, such as free-stall beds. Alternatively, slower oscillation may be desired in other areas, such as over cement alleyways. Programming can be changed at any time to meet the individual preferences of the animal herds person. Water output can be varied according to a pre-programmed schedule or through constant monitoring of current environmental conditions. Current temperature, humidity and wind conditions may be monitored and water output controlled accordingly by a variable-frequency-drive on the high-pressure water pump. Water output may also be controlled by switching nozzle sizes, instead of or in addition to changing pump pressure output. In conjunction with programmable oscillation, programmable water output allows the herds person to fine tune the animal's environment for maximum economic gain and animal comfort.
[0005] However, the linkage mechanism used with the prior disclosed cooling system may include rigid linkage arms or cables which prevent each fan in the system from being capable of oscillating a complete 360 degrees. This limitation means there are “hot spots” where the fans are unable to provide cooling for the livestock. In addition, the linkage mechanisms may be overly complicated, resulting in increased cost, maintenance and/or downtime. A livestock cooling system is desired in which the cooling fans are able to oscillate a complete 360 degrees, where the connecting linkage is relatively simple.
SUMMARY OF THE INVENTION
[0006] The present invention is directed to a fan for a livestock cooling system, where the fan is capable of oscillating a complete 360 degrees through the use of simple linkage. The disclosed fan is adaptable to be used with previously disclosed cattle cooling systems which provide for programmable oscillation of circuits of fans. The disclosed fan may be configured to emit water at high pressure so as to result in flash evaporation of the extremely small water particles which come into contact with any warm surface such as the skin of an animal or person.
[0007] The disclosed livestock cooling apparatus comprises an electrically-powered fan, where the fan creates an air stream. The fan comprises a fan blade, a fan motor, and a fan enclosure. The fan blade is operably attached to the fan motor, and the fan blade and fan motor are mounted in the fan enclosure. The fan enclosure is attached to a fan yoke. The cooling apparatus further comprises a drive shaft having a first end and a second end. The first end of the drive shaft is coupled to the fan yoke. An attachment member attached to a first support means supports the fan enclosure. The attachment member has a top, a bottom, and an aperture extending through the attachment member from the top to the bottom. Bearing means are attached to the attachment member, where the bearing means are disposed within the aperture. The bearing means and aperture are adapted for receiving the drive shaft therethrough. A first pulley is attached to the second end of the drive shaft. Oscillation means are connected to the first pulley for rotating the fan through a plurality of rotational positions. The apparatus may include means for injecting water droplets into the air stream of the fan.
[0008] These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 is a perspective view of the disclosed livestock cooling fan.
[0010] [0010]FIG. 2 is a front view of the disclosed livestock cooling fan.
[0011] [0011]FIG. 3 is perspective view of one embodiment for placement of an oscillation motor and pump motor.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0012] Referring now specifically to the drawings, FIG. 1 shows the disclosed livestock cooling apparatus 10 . The apparatus comprises an electrically-powered fan 12 , the fan comprising a fan blade 14 , a fan motor 16 , and a fan enclosure 18 . The fan blade 14 is operably attached to the fan motor 16 . The fan motor 16 and the fan blade 14 are mounted in the fan enclosure 18 . As shown in FIG. 1, the fan enclosure 18 is attached to a fan yoke 20 . The fan yoke 20 may be attached to the outsides of the fan enclosure 18 as shown in FIG. 1, so that the fan enclosure is enclosed within the fan yoke 20 . In this embodiment, the angle of the fan enclosure 18 , and therefore the angle of the air stream 22 created by the fan, may be adjusted with respect to the ground, allowing the user to adjust the direction of the air stream. The fan yoke 20 may be constructed from square or rectangular steel stock and may be configured in the U-shape depicted in FIG. 1 and FIG. 2.
[0013] A drive shaft 24 is coupled to the fan yoke 20 , the drive shaft having first end 26 which is coupled to the yoke, and second end 28 to which is attached a first pulley 30 .
[0014] Drive shaft 24 is supported within bearing means 32 . Bearing means 32 are supported attachment member 34 , which is attached to a support means 36 . As shown in FIG. 1 and FIG. 2, the attachment member may be attached to a variety of support means, including a structural member of a livestock protective structure, such as a barn or shade structure, where the structure has a roof 38 connected to support means 36 .
[0015] The attachment member 34 may have a top 40 and a bottom 42 . An aperture extends through the attachment member 34 from the top 40 to the bottom 42 . The attachment member 34 may be constructed from square or rectangular iron stock. Attachment member 34 may be attached to support means 36 with U-bolts, or other suitable attachment means including bolting and welding. Bearing means 32 are disposed within the aperture of attachment member 34 , where the bearing means and aperture are adapted for receiving drive shaft 24 therethrough.
[0016] First pulley 30 is attached to a second end 28 of drive shaft 24 . A stop collar 44 or other retaining device is attached to drive shaft 24 above bearing means 32 , such that the stop collar 44 or retaining device engages the top of bearing means 32 to support the weight of the fan 12 and the yoke 20 . Oscillation means are connected to the first pulley 30 for rotating the first pulley 30 , the drive shaft 24 , the fan yoke 20 and the fan 12 through a plurality of rotational positions ranging up to a complete 360 degree rotation. The oscillation means may comprise an oscillation motor 46 attached to support means 36 , where a second pulley 48 is operably connected to the oscillation motor 46 , and cables 50 connect the second pulley 48 to the first pulley 30 .
[0017] As depicted in FIG. 1 and FIG. 2, cables 50 form looped belts, which engage any one of the several grooves on first pulley 30 and second pulley 48 . As further shown in FIG. 1 and FIG. 2, additional looped belt cables 50 may be attached to first pulley 30 and/or second pulley 48 , thereby allowing a series of fans to be driven by a single oscillation motor 46 . A third pulley 52 , attached to support means 36 , may be used to change the direction of the cables as required by the desired configuration of fans.
[0018] Bearing means 32 may comprise a first bearing 32 A mounted on the top 40 of attachment member 34 and a second bearing 32 B mounted on the bottom 42 of the attachment member 34 . As an alternative, bearing means 32 may comprise a single bearing disposed within the aperture of the attachment member 34 .
[0019] Oscillation motor 46 may be electrically connected to a variable frequency drive, such as a Series No. VSDO7 manufactured by SQD. The variable frequency drive may be located within a local control panel 54 . A programmable controller, such as a IDEC Microsmart series, may also be contained within the local control panel 54 . The programmable controller may be equipped with a central processing unit, a real time clock module, a RS 485 module, an analog input and output module, digital input modules and digital output modules.
[0020] As an alternative embodiment to the system disclosed in FIGS. 1 and 2, a separate oscillation motor 46 may be directly attached to each drive shaft 24 , eliminating the need for cables 50 or other linkage.
[0021] The rotational position of each fan 12 may be sensed by a position indication device 56 , which may be mounted either at each individual fan 12 or, because fewer position indication devices 56 are required, at the oscillation motor 46 which drives a circuit of fans. The position indication device 56 is adapted to produce a signal in response to the rotation, i.e., oscillation, of the fan 12 , as monitored directly from the fan 12 , or in response to the rotation of the shaft of the oscillation motor 46 . A position indication device 56 at either location will provide a signal indicating the rotational position of each fan 12 being oscillated by the oscillation motor 46 . The output signal from the position indication device 56 may be transmitted to local control panel 54 or to a remote panel. An acceptable position indication device is a series 755 encoder available through Encoder Products Corp. of Sand Point, Id., or a Rotary Cam available through Electro Cam Corp. of Concord, Ontario.
[0022] The disclosed apparatus may also comprise means for injecting water droplets into the air stream 22 of the fan 12 . One means of injecting water droplets into the air stream 22 comprises delivering water to a mist ring 58 of each fan 12 through a high pressure water line 48 . Stainless steel or other corrosion resistant materials with acceptable pressures ratings are acceptable materials for construction of the mist ring 58 . A plurality of nozzles are attached to the mist ring 58 . The nozzles may be screwed into female connections which are welded to mist ring 58 , or otherwise attached. Water is delivered into a high pressure water line 60 by a pump 62 . Included among acceptable pumps are plunger pumps available through General Pump of Mendota Heights, Minn. or Cat Pumps of Minneapolis, Minn. Pump 62 is driven by pump motor 64 . The pump flow rate of pump 62 , and thus outlet pressure, may be controlled by various pressure control means. For example, the pump flow rate may be increased or decreased by controlling the revolutions per minute of motor 64 with a motor variable frequency drive, resulting in increased or decreased output pressure. The pump motor variable frequency drive may be located in local control panel 54 . High pressure water line 60 may be equipped with a swivel to further enable the fan to rotate a complete 360 degrees. The lengths of water line 60 and the power line 66 to the motor should be sized to allow a complete 360 degree rotation.
[0023] When water droplets are injected into the air stream 22 of each fan 12 , there is the possibility of creating a drench, a mist, or a fog, depending upon, among other factors, including environmental conditions, the volume of injected water, the injection pressure, and the droplet size. A drench showers the animal, wetting the animal to its skin, but is not normally a suitable cooling method when the animal is in its bedding area or is being milked. With a mist, the water droplets injected into the air stream 22 are smaller than with a drench, but the air becomes saturated with continued water injection, resulting in the animals and bedding becoming wet. A mist creates an undesirable water layer on the animal which acts as an insulator and retains heat. With fog, water is emitted through very small diameter nozzles at a sufficiently high pressure so as to result in extremely small water particles. These water particles will flash evaporate when the particles come into contact with any warm surface such as the skin of an animal or person, resulting in a cool animal environment with little wetting of the animal's hair-coat and virtually no wetting of the animal's bedding.
[0024] The disclosed cooling apparatus may be used with systems which monitor environmental conditions with environmental sensing devices, such as a temperature probes and/or a humidity probes, which transmit a signal to process control equipment, which provides an output signal to end devices which adjust water pressure and water volume accordingly. For example, the input to the process controller from a temperature probe may indicate the need for additional fog, so the process controller provides an output signal to a variable speed drive connected to pump motor 64 , increasing pump speed so that additional water may be injected for generating fog. It has been found that a nozzle diameter of approximately 0.02 inches and injection pressures ranging from 500 to 1200 psi provide the desired water particle size of approximately 8 to 30 microns.
[0025] While the above is a description of various embodiments of the present invention, further modifications may be employed without departing from the spirit and scope of the present invention. For example, the size, shape, position and/or material of the various components may be changed as desired. Thus the scope of the invention should not be limited by the specific structures disclosed. Instead the true scope of the invention should be determined by the following claims. | A livestock cooling apparatus is disclosed, the apparatus comprising an electrically-powered fan, which is capable of oscillating 360 degrees. The apparatus may be used in conjunction with a programmable cooling system for livestock which allows each fan in the system to be programmed to sweep a designated area according to observed environmental conditions or according to the time of day. The disclosed cooling apparatus may further comprise means for injecting water into the airstream created by the fan to provide for evaporative cooling of the livestock. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is related to and claims the priority of U.S. Provisional Patent Application No. 61/647,102 filed May 15, 2012, which is hereby incorporated herein by reference in its entirety.
BACKGROUND
Field
Communication systems, such as the long term evolution (LTE) of the third generation partnership project (3GPP) may benefit from various optimizations, such as optimizations related to smart phone technology. More particularly, diverse data applications may benefit from enhancements such as physical uplink control channel optimization.
Description of the Related Art
LTE radio access network (RAN) enhancements for diverse data applications can include, for example, providing improved always-on connectivity. For example, mechanisms at the RAN level may be needed to enhance the ability of LTE to handle diverse traffic profiles. Under such traffic loads, the improvements may allow for better trade-offs to be achieved when balancing the needs of network efficiency, UE battery life, signaling overheads, and user experience/system performance.
In current LTE systems, a physical uplink control channel (PUCCH) resource allocation is configured by a radio resource controller (RRC) in semi-static way. For example, the RRC reconfiguration message may take up to tens or one hundred milliseconds to take effect. Once configured, the allocated resource is reserved and can conventionally be changed only via RRC reconfiguration, which is at the cost of RRC signaling. In practice, such RRC reconfiguration procedure happens rarely, even when user equipment (UE) traffic characteristic is changed, to avoid signaling overhead.
For example, scheduling request (SR) resource can be configured by an evolved Node B (eNB) in an initial stage after an RRC establishment procedure. If a long periodicity is configured, the configured periodicity may not fit if real-time application starts, such as voice over internet protocol (VoIP) or gaming. Otherwise if a short periodicity is configured, most of SR resource may be wasted. RRC reconfiguration can be used to adjust PUCCH configuration. In certain cases, however, RRC reconfiguration requires changing cell-specific parameters, such as physical resource block (PRB) numbers of channel quality indicator (CQI), to meet the demands. Such a change will impact all UEs in the cell and can potentially cause a significant effect on throughput during the transition phase. RRC reconfiguration thus can lead to reconfiguring a large number of user equipment (UEs) in a relatively short window of time.
3GPP has a variety of approaches for providing PUCCH usage efficiency. One way is to extend periodicity. Another way is to provide a sharing mechanism whereby the same SR resource is allocated to multiple UEs. This approach assumes that each UE may have only a few packets transmission in background services. If multiple UEs happen to transmit a data packet at the same time, user contention over the same PUCCH resource and collisions may occur. In this case, the eNB may be unable to identify which UE is transmitting the SR signal, leading to the need for a contention resolution mechanism.
Another approach is discontinuous reception (DRX) CQI masking, as described in 3GPP technical specification (TS) 36.331, which is hereby incorporated herein by reference. When a UE works in DRX mode, CQI transmission can be disabled in off-duration. This can permit another UE to transmit a CQI signal during the off-duration of the DRX-mode UE. In this way, multiple UEs can share a same CQI resource.
A further approach is PUCCH release with time alignment timer (TAT) configuration. In Release 8 (Rel-8), one timer, TimeAlignementTimer, is used to control UL synchronization. Before TAT expiry, the UE can be indicated a new time advanced (TA) value to keep UL synchronization. If TA has not been updated until TAT is expired, this UE can enter out-of-sync mode, and can then release PUCCH resource. The eNB could set a small value for TAT to force UE into out-of-sync mode. For example, a minimum TAT value of 500 ms can be set.
SUMMARY
According to certain embodiments, a method may include configuring, with radio resource control signaling, a physical uplink control channel resource to one or more devices. The method may also include indicating to each device of the one or more devices, which part of the resource to use.
In certain embodiments, an apparatus may include at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to configure, with radio resource control signaling, a physical uplink control channel resource to one or more devices. The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to indicate to each device of the one or more devices, which part of the resource to use.
An apparatus, according to certain embodiments, may include means for configuring, with radio resource control signaling, a physical uplink control channel resource to one or more devices. The apparatus may also include means for indicating to each device of the one or more devices, which part of the resource to use.
A non-transitory computer readable medium, in certain embodiments, may be encoded with instructions that, when executed in hardware, perform a process. The process may include configuring, with radio resource control signaling, a physical uplink control channel resource to one or more devices. The process may also include indicating to each device of the one or more devices, which part of the resource to use.
BRIEF DESCRIPTION OF THE DRAWINGS
For proper understanding of the invention, reference should be made to the accompanying drawings, wherein:
FIG. 1 illustrates three resource modes according to certain embodiments.
FIG. 2 illustrates seven resource modes according to certain embodiments.
FIGS. 3A and 3B provide exemplary signaling sequences showing how the SR periodicity can be changed from 40 ms to 80 ms and vice versa, according to certain embodiments.
FIG. 4 illustrates a method according to certain embodiments.
FIG. 5A illustrates a traffic status change use case according to certain embodiments.
FIG. 5B illustrates a network load change use case according to certain embodiments.
FIG. 6 illustrates a system according to certain embodiments.
DETAILED DESCRIPTION
While radio resource control (RRC) signaling can be used for semi-static configuration, certain embodiments provide a faster and more agile signaling with reduced overhead compared to actual RRC-based implementations.
For example, certain embodiments relate to physical uplink control channel (PUCCH) resource allocation. According to certain embodiments, one PUCCH resource (for example, channel quality indicator CQI, scheduling request SR resource or acknowledgment/negative acknowledgment (ACK/NACK) resource) can be configured with radio resource control (RRC) signaling to two (or several) UEs and a Medium Access Control (MAC) Information element can be used to indicate to the UEs which part of the resource (for example, even/odd half of the resource) to use. More specifically, the invention introduces a mechanism for allocating partial resources by adjusting the periodicity of the PUCCH resource, and activating/deactivating them using an information element or command.
Enhancements for diverse data applications (EDDA) optimization can variously include signaling load reduction, power saving and system efficiency improvement. In LTE, PUCCH carries ACK/NACK, CQI and SR. Certain embodiments, therefore, are related to PUCCH configuration optimization, and can improve PUCCH usage efficiency and signaling.
For example, certain embodiments provide a method to allocate PUCCH resources flexibly. One aspect of certain embodiments is an information element/command that indicates PUCCH resource share and its activation/deactivation with respect to the UE. FIG. 4 illustrates a method according to certain embodiments.
As shown in FIG. 4 , at 410 , an eNB can configure a dedicated PUCCH resource to one UE through RRC signaling. Additionally, an information element or a MAC command can be used, at 420 , to indicate final resource of PUCCH. In some embodiments, the information element may also be transmitted within the MAC command. Alternatively, another command suitable for signaling the resource allocation to the UE may be used. If the UE has not received this command, the assigned PUCCH resource can follow RRC configuration. However, if the UE has received this command, assigned PUCCH resource may follow this new indication. The PUCCH resource may comprise, for example, physical resource blocks (PRB) in a frequency domain.
When UE traffic status changes or network load changes, at 430 , eNB can adjust a UE's PUCCH resource allocation with an information element (IE) or MAC command. The time of sending the information element (IE) or MAC command may thus depend on the system load, traffic information, and the like. Moreover, at 440 , this command can support PUCCH resource allocation from full resource status to shared resource status, as well from shared resource status to full resource status. Additionally, at 450 , the command can be used to trigger activation and/or deactivation of the PUCCH resource. The command may trigger deactivation of the PUCCH resource, for example by forcing a time alignment timer to expire. After receiving this command, UE may follow the existing behavior defined for the time alignment timer expiry, namely to release the PUCCH and enter out-of-sync mode.
Various uses of certain embodiments are possible. For example, certain embodiments can address a traffic status change as shown in FIG. 5A . At 510 , an eNB can provide a UE with a partial resource when the UE has low active traffic. At 520 , the UE can begin high traffic activity, such as VoIP or gaming. Accordingly, at 530 , the eNB can allow this UE to use the full assigned resource. On the contrary, PUCCH resource allocation could be changed from full resource to partial resource.
FIG. 5B , by contrast illustrates a network load change use case. At 540 , an eNB allocates one UE with a full resource. The network can begin to have a higher load at 550 . Then, at 560 , the eNB can starts to reduce the resource of the UE, in order to admit other UEs in the cell, while providing the new UEs the uplink (UL) signaling resources it needs. On another hand, if network load decreases at 570 , PUCCH resource allocation could be changed from shared state into full resource state, at 580 .
Certain embodiments can provide, using the above information element or MAC command, fast and dynamic resource allocation according to quality of service (QoS) and network load. Certain embodiments can also provide signaling overhead reduction, especially RRC signaling overhead related to reconfigurations. Certain embodiments can avoid/minimize the need of broadcasting new PUCCH configurations with consequent drawbacks in the transition phase. Moreover, certain embodiments can allow multiple users to share same allocation of PUCCH resources. Furthermore, certain embodiments can trigger the activation or deactivation of PUCCH resources.
Certain embodiments can be implemented in various ways. One simple implementation mechanism is using a few bits to indicate PUUCH resource (such as CQI resource) allocation. For example, in one embodiment 0 represents an even part of the resource and 1 represents an odd part of the resource. Additional information can be used for disabling this sharing allocation and for normal full resource allocation. Total information bits number is 2, in this case. Table 1 illustrates this command:
TABLE 1
00
Disable sharing(full resource)
01
Even resource
10
Odd resource
11
Null or stopping CQI reporting or
CQI resource deactivation
As a special configuration, a MAC command can be used to deactivate the CQI resource of one UE when the UE has been allocated to one resource via RRC signaling or MAC command. This resource can be released and allocated to another UE. Furthermore, if the resource has been deactivated, it also could be activated via this MAC command. As shown in table 1, the first three entries could be seen as the CQI resource activation, the fourth entry could be used to deactivate the CQI resource.
Based on the activation and deactivation of CQI resource, one possible resource allocation mode is the combination of RRC signaling and MAC command. For example, in a particular case, RRC signaling is used to allocate a certain physical resource for one UE, while a MAC command is used to trigger the activation of this resource share. Hence, this mechanism allows overbooking this resource for multiple UEs.
FIG. 1 illustrates three resource modes according to certain embodiments. As shown in FIG. 1 , full resource state in this case means that a periodic CQI resource with 10 ms period has been assigned to one UE. Even half and odd half can be separated out from a full resource. Furthermore, in some embodiments, another share or part of the resource can be assigned to one UE.
FIG. 2 , on the other hand, illustrates seven resource modes according to certain embodiments. As an enhancement of two bit indication, eNB can use two steps indications to assign a quarter of one PUCCH resource. For example, in the first step “01” could represent even half of one resource. In the second step, two bits “01” could further indicate even half of assigned half resource in last step. Similarly, two bits “10” could further indicate the odd half of assigned half resource in last step.
If finer allocation is allowed, more information bits can be used for addressing it. For example, when 2 bits are used, 00 can mean first quarter, 01 can mean second quarter, 10 can mean third quarter, and 11 can mean fourth quarter. An additional disabled status can also be indicated. Furthermore, a three bit command can include two bit items to be more complete. Table 2 provides an example, where the first seven entries could be seen as the CQI resource activation, the eighth entry could be used to deactivate the CQI resource:
TABLE 2
000
Disable sharing(full resource)
001
Even half
010
Odd half
011
First quarter resource
100
Second quarter resource
101
Third quarter resource
110
Fourth quarter resource
111
Null or stopping CQI reporting or
CQI resource deactivation
In FIG. 2 , one full resource is divided into four parts evenly. Three bits could be used to indicate all possible combinations, as shown above in Table 2.
Not only can CQI be allocated with this mechanism, but also SR or other physical uplink control channel resource allocation can also be performed. Thus, SR resource pace can be adjusted to fit for network load and traffic status. Similar two bit commands for SR resources are shown in Table 3:
TABLE 3
00
Disable sharing
01
Even resource
10
Odd resource
11
Null or stopping SR tranmission
or SR resource deactivation
A combined signal format can be provided, which can control CQI and SR resource allocation simultaneously:
CQI control
SR control
TAT expiry
This command signal can include three fields: one is for CQI control, a second is for SR control, and the last field can be used to release a PUCCH resource. When TAT expiry is enabled, the UE can release all assigned PUCCH resources.
FIGS. 3A and 3B illustrate exemplary signaling sequences showing how the SR periodicity can be changed from 40 ms to 80 ms and vice versa, according to certain embodiments.
FIG. 3A illustrates a single user reconfiguration case. As shown in FIG. 3A , initial RRC connection configuration or reconfiguration can take place at 310 between an eNB and UE 1 . Under this configuration, the SR period may be 40 ms. Then, the eNB can detect that UE 1 has only low active traffic, at 320 . Therefore, the eNB can, at 330 , send a designation “01,” which can indicate that UE 1 is only to use the even resources. Thus, the effective or equivalent SR period is now 80 ms.
Later, at 330 , the eNB may detect that VoIP is initiated at UE 1 . In this case, the eNB can send a designation “00” at 340 , which can disable sharing, restoring the UE 1 to an SR period of 40 ms.
FIG. 3B illustrates a two users sharing case. As shown in FIG. 3B , initial RRC connection configuration or reconfiguration can take place at 310 between an eNB and UE 1 . Then, at 325 , the eNB can detect that there is insufficient PUCCH. Therefore, the eNB can send an indication of “01,” to inform UE 1 that only even resources are valid. With such configuration, the remaining part of the PUCCH resources may be allocated to other user(s). After that, UE 2 can connect to the network at 345 . At the 355 , the eNB can use RRC connection configuration/reconfiguration, an information element or a MAC command to give UE 2 the same PUCCH configuration as UE 1 .
Then, at 365 , the eNB can inform UE 2 using an indication of “10,” that UE 2 is only to use the odd resource. After that, at 375 , UE 1 and UE 2 can share a same resource. At 385 , the eNB may detect that VoIP has been initiated at UE 1 . Therefore, at 395 , the eNB can reconfigure UE 1 to use a new resource that is not shared with UE 2 .
FIG. 6 illustrates a system according to certain embodiments of the invention. In one embodiment, a system may include several devices, such as, for example, eNB 610 and UE 620 . The system may include more than one UE 620 , although only one is shown for the purposes of illustration. Each of these devices may include at least one processor, respectively indicated as 614 and 624 . At least one memory is provided in each device, and indicated as 615 and 625 , respectively. The memory may include computer program instructions or computer code contained therein. Transceivers 616 and 626 are provided, and each device may also include an antenna, respectively illustrated as 617 and 627 . Other configurations of these devices, for example, may be provided. For example, eNB 610 and UE 620 may be configured for wired communication, rather than wireless communication, and in such a case antennas 617 and 627 would illustrate any form of communication hardware, without requiring a conventional antenna.
Transceivers 616 and 626 can each, independently, be a transmitter, a receiver, or both a transmitter and a receiver, or a unit or device that is configured both for transmission and reception.
Processors 614 and 624 can be embodied by any computational or data processing device, such as a central processing unit (CPU), application specific integrated circuit (ASIC), or comparable device. The processors can be implemented as a single controller, or a plurality of controllers or processors.
Memories 615 and 625 can independently be any suitable storage device, such as a non-transitory computer-readable medium. A hard disk drive (HDD), random access memory (RAM), flash memory, or other suitable memory can be used. The memories can be combined on a single integrated circuit as the processor, or may be separate therefrom. Furthermore, the computer program instructions stored in the memory and which may be processed by the processors can be any suitable form of computer program code, for example, a compiled or interpreted computer program written in any suitable programming language.
The memory and the computer program instructions can be configured, with the processor for the particular device, to cause a hardware apparatus such as eNB 610 and UE 620 , to perform any of the processes described above (see, for example, FIGS. 1-5B ). Therefore, in certain embodiments, a non-transitory computer-readable medium can be encoded with computer instructions that, when executed in hardware, perform a process such as one of the processes described herein. Alternatively, certain embodiments of the invention can be performed entirely in hardware.
Furthermore, although FIG. 6 illustrates a system including an eNB 610 and a UE 620 , embodiments of the invention may be applicable to other configurations, and configurations involving additional elements, as illustrated and discussed herein. For example, multiple user equipment devices can be present.
According to certain embodiments, a method includes configuring, with radio resource control signaling, a physical uplink control channel resource to one or more devices. The method also includes indicating to each device of the one or more devices, which part of the resource to use.
The resource can be at least one of a channel quality indicator resource or a scheduling request resource.
The resource can further be at least one of an acknowledgment/negative acknowledgment resource, a precoding matrix indicator resource and a rank indication resource.
The indicating can include indicating with a control information element, such as a medium access control information element.
The indicating the part of the resource to use can include indicating an alternating even or odd half of the resource, a quarter of the resource, or full use of the resource.
The indicating the part of the resource to use can include indicating different parts of the same resource to multiple devices.
The method can include adjusting a periodicity of the resource by allocating partial resources.
The method can also include activating or deactivating an allocation of the resource using at least one of an information element, a medium access control command, or radio resource control signaling.
The method can include activating or deactivating the resource using at least one of an information element, a medium access control command or radio resource control signaling.
The deactivating the allocation of the resource may include forcing a time alignment timer to expire.
The method can further include detecting a change in at least one of network load or traffic status of a device of the one or more devices, and adjusting the resource to use for a device of the one or more devices based on the change.
The method can additionally include time division multiplexing of multiple devices on the same physical uplink control channel resource.
In certain embodiments, an apparatus includes at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to configure, with radio resource control signaling, a physical uplink control channel resource to one or more devices. The at least one memory and the computer program code are also configured to, with the at least one processor, cause the apparatus at least to indicate to each device of the one or more devices, which part of the resource to use.
The resource can be at least one of a channel quality indicator resource or a scheduling request resource.
The resource can further be at least one of an acknowledgment/negative acknowledgment resource, a precoding matrix indicator resource and a rank indication resource.
The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to indicate the part of the resource to use with a control information element, such as a medium access control information element.
The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to indicate the part of the resource to use by indicating an alternating even or odd half of the resource, a quarter of the resource, or full use of the resource.
The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to indicate the part of the resource to use by indicating different parts of the same resource to multiple devices.
The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to adjust a periodicity of the resource by allocating partial resources.
The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to activate or deactivate an allocation of the resource using at least one of an information element, a medium access control command, or radio resource control signaling.
The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to activate or deactivate the resource using at least one of an information element, a medium access control command or radio resource control signaling.
The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to deactivate the allocation of the resource by forcing a time alignment timer to expire.
The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to detect a change in at least one of network load or traffic status of a device of the one or more devices, and to adjust the resource to use for a device of the one or more devices based on the change.
The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to time division multiplex multiple devices on the same physical uplink control channel resource.
An apparatus, according to certain embodiments, includes configuring means for configuring, with radio resource control signaling, a physical uplink control channel resource to one or more devices. The apparatus also includes indicating means for indicating to each device of the one or more devices, which part of the resource to use.
The resource can be at least one of a channel quality indicator resource or a scheduling request resource.
The resource can further be at least one of an acknowledgment/negative acknowledgment resource, a precoding matrix indicator resource and a rank indication resource.
The indicating can include indicating with a control information element, such as a medium access control information element.
The indicating the part of the resource to use can include indicating an alternating even or odd half of the resource, a quarter of the resource, or full use of the resource.
The indicating the part of the resource to use can include indicating different parts of the same resource to multiple devices.
The apparatus can include adjusting means for adjusting a periodicity of the resource by allocating partial resources.
The apparatus can also include activation means for activating or deactivating an allocation of the resource using at least one of an information element, a medium access control command, or radio resource control signaling.
The activation means can be configured to activate or deactivate the resource using at least one of an information element, a medium access control command or radio resource control signaling.
The deactivating the allocation of the resource may include forcing a time alignment timer to expire.
The apparatus can further include detecting means for detecting a change in at least one of network load or traffic status of a device of the one or more devices, and adjusting the resource to use for a device of the one or more devices based on the change.
The apparatus can additionally include multiplexing means for time division multiplexing of multiple devices on the same physical uplink control channel resource.
A non-transitory computer readable medium is, in certain embodiments, encoded with instructions that, when executed in hardware, perform a process. The process includes configuring, with radio resource control signaling, a physical uplink control channel resource to one or more devices. The process also includes indicating to each device of the one or more devices, which part of the resource to use.
The resource can be at least one of a channel quality indicator resource or a scheduling request resource.
The resource can further be at least one of an acknowledgment/negative acknowledgment resource, a precoding matrix indicator resource and a rank indication resource.
The indicating can include indicating with a control information element, such as a medium access control information element.
The indicating the part of the resource to use can include indicating an alternating even or odd half of the resource, a quarter of the resource, or full use of the resource.
The indicating the part of the resource to use can include indicating different parts of the same resource to multiple devices.
The process can include adjusting a periodicity of the resource by allocating partial resources.
The process can also include activating or deactivating an allocation of the resource using at least one of an information element, a medium access control command, or radio resource control signaling.
The process can include activating or deactivating the resource using at least one of an information element, a medium access control command or radio resource control signaling.
The deactivating the allocation of the resource may include forcing a time alignment timer to expire.
The process can further include detecting a change in at least one of network load or traffic status of a device of the one or more devices, and adjusting the resource to use for a device of the one or more devices based on the change.
The process can additionally include time division multiplexing of multiple devices on the same physical uplink control channel resource.
One having ordinary skill in the art will readily understand that the invention as discussed above may be practiced with steps in a different order, and/or with hardware elements in configurations which are different than those which are disclosed. Therefore, although the invention has been described based upon these preferred embodiments, it would be apparent to those of skill in the art that certain modifications, variations, and alternative constructions would be apparent, while remaining within the scope of the invention. | Communication systems, such as the long tem evolution (LTE) of the third generation partnership project (3GPP) may benefit from various optimizations, such as optimizations related to smart phone technology. More particularly, diverse data applications may benefit from enhancements such as physical uplink control channel optimization. According to certain embodiments, a method can include configuring, with radio resource control signaling, a physical uplink control channel resource to one or more devices. The method can also include indicating to each device of the one or more devices, which part of the resource to use. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to apparatus for the purification of a liquid, such as water, by reverse osmosis.
2. Prior Art
In the specification of U.S. Pat. No. 4,124,488 there is described an apparatus for the reverse osmosis purification of water or other fluid comprising a module including a reverse osmotic membrane, a fluid inlet and fluid outlet for passage of fluid through the module over one surface of the membrane and an outlet for the passage of purified fluid out of the module from the opposite surface of the membrane, together with a ram having a piston or diaphragm in a cylinder for forcing fluid from the front face of the piston or diaphragm through a valve to the fluid inlet of the module, the ram having an operating rod extending outwardly from the rear face of the piston or diaphragm and means, including a first controlled valve connecting said fluid outlet from the module to the cylinder to admit returned fluid from the module onto the rear face of the piston or diaphragm and a second control valve to control discharge from the rear of the piston or diaphragm. Such apparatus will be referred to hereinafter as apparatus of the kind described.
With this construction, a fluid such as seawater is forced by the ram into the module. A valve is provided between the ram and the module to prevent return of fluid from the module on the return stroke of the ram; this may be a non-return valve or it may be a valve which is controlled by the fluid pressure or by the movement of the ram or in synchronism therewith. On the forward stroke of the ram, some water may pass through the membrane and the remainder of the fluid is returned to the rear face of the piston or diaphragm.
As is explained in the aforementioned specification, with this arrangement, fluid may be forced into the module at a very high pressure such that water purification can be obtained. For brackish water, a pressure of the order of 300 to 500 p.s.i. would be necessary whilst for seawater, since the osmotic pressure is higher, a pressure typically of the order of 600 to 1000 p.s.i. might be necessary. The construction described above enables these high pressures to be obtained economically and efficiently because the return fluid from the membrane is applied to the rear surface of the piston or diaphragm. This rear surface, because of the presence of the operating rod, has a slightly smaller effective area. The pressure in the system builds up until a pressure is reached at which water will pass through the membrane on each stroke in equivalent volume to the difference in volume between the rear and front ends of the cylinder due to the presence of the operating rod. Power has to be supplied to the operating rod and the required work for each stroke depends only on the difference of the front and rear face areas, the pressure and the length of the stroke. The device is thus self-regulating and tends to operate in a condition where the proportion of water passing through the membrane to the total inlet fluid is equal to the ratio of the operating rod cross-section to the piston or diaphragm front face area. There is thus no need for any pressure regulation by relief valves. No adjustment is required for variations of salinity and the same equipment may be used for seawater as for slightly brackish water. Although it is convenient to refer to water, the apparatus may be used for reverse osmosis treatment of other fluids.
Reference may also be made to the following further U.S. Pat. Nos. 1,909,145; 3,405,058; 3,493,495; 3,498,910; 3,825,122.
BRIEF SUMMARY OF THE INVENTION
It is one of the objects of the present invention to provide a reverse osmosis liquid purification apparatus of the kind described above in which the necessity for a mechanical reciprocating drive system is avoided.
According to this invention, apparatus for the reverse osmosis purification of water or other fluid comprises a module including a reverse osmotic membrane, a fluid inlet and fluid outlet for passage of fluid over one surface of the membrane and an outlet for the passage of purified fluid out of the module from the opposite surface of the membrane together with a plurality of similar cylinders each having a piston or diaphragm and each arranged for forcing fluid from the front face of the piston or diaphragm through a separate valve to the fluid inlet of the module, the pistons or diaphragms being mechanically interconnected by operating rods extending from their rear faces to operate in a cyclic sequence, means arranged for supplying fluid under pressure from a fluid supply to the front end of each cylinder through a separate non-return valve, and controlled valve means operative selectively to connect the rear end of each cylinder alternately to the fluid outlet of the module and to a discharge in synchronism with said cyclic sequence.
In this construction, the pump means supply the fluid to be treated to the front ends of the various cylinders for subsequent forcing at high pressure into the module. This fluid from the pump means provides the necessary driving power for operating the pistons or diaphragms in the various cylinders. There is thus no need for any gearbox or mechanical drive to the pistons or diaphragms. If there are three or more cylinders, the pistons or diaphragms may have their operating rods interconnected by a crank-shaft; this crank-shaft however is free-running, the drive power coming from the pump.
In the simplest case however only two cylinders are employed and, in this case, the pistons or diaphragms may be directly connected by an operating rod.
In a preferred embodiment of the invention apparatus for the reverse osmosis purification of water or other fluid comprises a module including a reverse osmotic membrane, a fluid inlet and fluid outlet for passage of fluid over one surface of the membrane and an outlet for the passage of purified fluid out of the module from the opposite surface of the membrane together with ram means comprising a pair of similar cylinders each having a piston or diaphragm and each arranged for forcing fluid from the front face of the piston or diaphragm through a separate valve to the fluid inlet of the module, the cylinders being aligned with a common operating rod extending from the rear face of one piston or diaphragm to the rear face of the other piston or diaphragm, pump means arranged for supplying fluid under pressure from a fluid supply through separate non-return valves to the front end of each ram and controlled valve means operative selectively to connect the fluid outlet from the module to the rear end of one ram and to connect the rear end of the other ram to a discharge or vice-versa, with control means for said valve means operative to change-over the connections when the pistons or diaphragms are at or near the end of a stroke. The aforesaid separate valves through which fluid is forced from the front face of the piston or diaphragm to the module are conveniently non-return valves but they could be further valves controlled by said control means.
With this apparatus, the pump means can be a continuously running pump, conveniently an impeller or gear or vane pump. The outlet from this pump need only be at a very low pressure compared with the pressure required in the module and might typically be 80 p.s.i. This output is applied through non-return valves to the front ends of both rams (considering a system with only two cylinders). One of these rams has its rear end connected to discharge. The other ram has its rear end connected to the high pressure outlet from the module. The two rams are interconnected by the common operating rod. Considering the ram with its rear end connected to discharge, the piston or diaphragm will tend to move towards the rear end. The pump pressure, applied over the whole front face, will exert a force on the operating rod, which force is applied to the other piston or diaphragm and is additive with the return fluid pressure from the module on the rear face of that piston or diaphragm. Movement of the two pistons or diaphragms thus takes place if the required module pressure is developed on the front face of the second piston or diaphragm, i.e. if the force in the operating rod is sufficient to overcome the effect of the different areas of the front and rear faces which are both subject to the module pressure. It will thus be seen that the required pump pressure is a fraction of the required module pressure determined by the ratio of the cross-sectional areas of the operating rod and of the piston.
As described in the aforementioned U.S. Specification No. 4,124,488, the apparatus will inherently operate at a module pressure such that the extraction ratio is equal to the ratio of the cross-sectional areas of the operating rod and piston. If the extraction ratio is less than this, then the volume of return fluid fed to the rear face of a piston will be greater than can be accommodated by movement of the piston to force the appropriate volume of fluid into the module. The pressure inherently builds up to give the required extraction ratio. In the apparatus of the present invention, no movement of the pistons will occur until the pump pressure has built up to the necessary pressure to provide the required operating force. Although the pump is connected to the front ends of both cylinders, the non-return valve will be closed between the pump and that one of the cylinders which is supplying pressure fluid to the module. The other non-return valve will be open but fluid will only flow from the pump to the cylinder when the required pressure has developed. It is thus possible to use any pump means which will develop the required fluid pressure, which, as previously indicated, would typically be about 80 p.s.i. Flow will commence when the required pressure is reached. It will be seen that the pressures throughout the system are self-regulating; both the extraction ratio and the ratio of pump to module pressure are predetermined by choice of the ratio of operating rod cross-section to piston area.
The controlled valves have to change-over at or near the end of each stroke. These valves might be electrically operated or mechanically operated or hydraulically operated. Very conveniently hydraulic operation is employed, making use of the rise in pressure in the output from the pump at the end of a stroke (when flow must cease). As soon as the valves change-over, the pressure will fall and thus there is a pressure-pulse at each end of each stroke. Conveniently a reversing actuator, e.g. a semi-rotary flow reversing device, is provided which, on one pulse, sets the valves in one position and, on the next pulse, reverses the valve positions. To avoid the pressure pulses, other means may be employed for detecting the end of a stroke, e.g. inductive sensing means for detecting the position of the piston; such means would conveniently be employed to control electrically operated valves.
The controlled valves may be spool or piston valves. They have to control fluid which may be at the module pressure. To operate such valves from the pump outlet fluid, it may be preferred to use pressure intensifying means.
In a particularly convenient arrangement, the controlled valves are operated hydraulically by a spool valve and the rise in pressure at the end of each operating stroke of the main pistons is utilized to effect reversal of the spool valve.
The two main cylinders may be mounted back-to-back. There would be no need for any bearings for the operating rod between the cylinders and only one seal, on this operating rod, would be necessary. There is no need for any tight seal between the pistons and cylinders because the pressures on the two sides of each piston are nearly equal if the cylinder is subject to module pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram illustrating one form of reverse osmosis liquid purification apparatus;
FIG. 2 is a diagram showing in further detail another construction of the apparatus;
FIGS. 3 and 4 are diagrams illustrating further valve operating arrangements;
FIGS. 5 and 6 are diagrams illustrating two further forms of reverse osmosis liquid purification apparatus; and
FIGS. 6a and 6b are diagrams illustrating part of the apparatus of FIG. 6 in different positions during a cycle of operation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, there is shown diagrammatically at 10 a reverse osmosis liquid purification module having a membrane 11 in a housing 12 with a fluid inlet 13 and fluid outlet 14 on one side of the membrane and a purified liquid outlet 15 on the other side of the membrane. This module may be constructed in the known manner, for example having a sheet of cellulose acetate or polyamide membrane material wound spirally with a liquid-conducting backing sheet around a perforated tube which receives the purified liquid. As another example, the known hollow fibre construction may be employed.
A rotary pump 20, e.g. an impeller pump or gear pump or vane pump driven by an electric motor feeds liquid to be purified at a pressure typically of 80 p.s.i. to ducts 21, 22 leading respectively via non-return valves 23, 24 to the front ends of two cylinders 25, 26 having pistons 27, 28 respectively. In some cases the fluid may be available under a suitable pressure without a pump, e.g. a water supply from a dam. These cylinders 25, 26 are aligned and the pistons are joined by a rigid connecting rod 29 extending between the rear faces of the two pistons. By means of valves 30, 31, the rear end of cylinder 25 is connected selectively either to the module outlet 14 or to a discharge 32. By means of valves 33, 34, the rear end of cylinder 26 is connected selectively either to the module outlet 14 or to the discharge 32. The valves 30, 31, 33 and 34 are controlled in synchronism with the operation of the pistons so that they change-over at or near each end of each stroke.
When fluid from pump 20 is entering the front end of cylinder 25, the rear end of that cylinder is connected to discharge 32 and thus the pump pressure on the piston applies a force to the connecting rod 29. This force, as previously explained, supplements the force on the rear face of piston 28 due to the module fluid pressure and, provided the pump pressure is sufficient, will cause fluid to be forced from the front end of cylinder 26 through a non-return valve 36 into the module inlet 13. A further non-return valve 37, between the module inlet and the front end of cylinder 25 prevents the pressurised fluid in the module from entering the front end of cylinder 25.
At the end of the stroke, the valves 30, 31, 33 and 34 are changed over by control means 40. These control means may be electrical, e.g. microswitches controlling solenoids operating the valves, or mechanical or hydraulic.
As previously explained, the apparatus will develop a pressure in the module such as will give an extraction ratio corresponding to the ratio of the operating rod section to the piston area. This ratio will also determine the pressure which will have to be developed by pump 20 to effect measurement of the pistons. The apparatus is self-regulating in this respect, inherently developing the required pressures.
Many types of valve control means may be used for controlling the valves 30, 31, 33 and 34. FIG. 2 illustrates a hydraulically operated system. In FIG. 2 there is shown a reverse osmosis system in many ways similar to that of FIG. 1 and the same reference characters are used to indicate corresponding elements. In the following description mention will be made only of the distinctive features of the construction of FIG. 2. In this arrangement use is made of the pressure pulse which occurs in the output from the pump 20 at the end of each stroke. When the pistons stop moving, the pressure will rise but, since the valves are then immediately actuated in a manner to be described later, the pressure falls again and thus there is in effect a pressure pulse at each end of each stroke. This pressure pulse is applied to a pulse actuator 45 and has a spring-loaded piston set so that it will jump open at a predetermined pressure. This pulse actuator operates a semi-rotary reversing switch 46 which switch, in one position connects the output of the pump 20 to one side 47 of a pressure intensifier 48 and, in the other position, connects the output of the pump to the other side 49 of the pressure intensifier. The side of the pressure intensifier to which the pump pressure is not employed is connected by the reversing switch to a discharge 50. The intensifier provides output at typically 1000 p.s.i. on one or other of two lines 51, 52 according to the setting of the reversing switch. The output on line 51 controls spool or piston valves 53, 54 for the rear end of cylinder 25 whilst the output on line 52 controls spool or piston valves 55, 56 for the rear end of cylinder 26. These valves are operated as previously described so that the rear end of each cylinder is connected either to the module outlet or to the discharge 32 according to the required direction of movement of the pistons.
The use of the pressure intensifier in FIG. 2 avoids the necessity for having large piston areas operating the valves. However this problem may be avoided by making use of an arrangement such as is shown in FIG. 3 in which there is a low-pressure-operated actuator 60 comprising a piston 61 in a cylinder 62 with rods 63, 64 extending through seals in the chamber wall. These rods serve to open ball valves 65, 66 respectively, the ball valves normally being held against their seats by the fluid pressure to be controlled. It will be appreciated that two such control devices would be required, one for each cylinder.
FIG. 4 illustrates another arrangement in which a solenoid 70 having operating rods 71, 72 actuates ball valves 74, 75 for controlling the connection of the rear face of one cylinder either to the module or to discharge as required. The solenoid is operated by a sensor 76 which might for example be an inductive sensor sensing the position of the piston. Separate induction coils may be provided at each end of the cylinder to provide sensing signals indicative of when the piston has reached the ends of the cylinder. It will be appreciated that it is merely necessary to sense when the piston is approximately at the end of the cylinder. The actual length of travel for each stroke is not critical. However the valves on the two cylinders will have to be operated simultaneously and thus one sensing system will be used to control the solenoid for operating the valves on both cylinders.
In FIG. 5 there is illustrated a construction in which the pressure rise at the end of the stroke is used not to operate directly valves controlling the ports for the main cylinder but to operate a spool valve controlling piloted valves for these ports.
In the following description, the same reference numerals will be used as in FIGS. 1 and 2 to illustrate corresponding components and mention will only be made of the distinctive features of the FIG. 5 construction.
A pilot piston and cylinder 80 controls valves 81 and 82 such that one of these valves is opened when the other one is closed and vice versa. The valve 81 connects the rear end of cylinder 25 to discharge whilst the valve 82 connects the rear end of that cylinder to the outlet 14 from the module. A second piloted valve comprises a piston and cylinder 83 operating valves 84, 85 such that one valve is open when the other is closed and vice versa. The valve 84 connects the rear end of cylinder 26 to the outlet 14 from the module 10 whilst the valve 85 connects the rear end of cylinder 26 to the discharge. The two piloted valves 80, 83 are operated in synchronism by applying pressure, as will be described later, to lines 86, 87 leading to one side of the pistons in these piloted valves and connecting the other sides via lines 88, 89 to discharge or, by applying the pressure to lines 88, 89 and connecting lines 86, 87 to discharge, forcing the piloted valves into their opposite position. This operation is achieved by means of a spool valve 90 having three spools 91, 92, 93 on a common connector rod 94 which forms the armature for a solenoid 95. Inlet pressure from the pump 20 is applied to an inlet port 96 and, according to the position of the spool valve, this pressure is applied either via an outlet port 97 to the aforementioned connectors 86, 87 or via an outlet port 98 to the aforementioned connector leads 88, 89. Outlets 100, 101 from the spool valve lead to the discharge and serve to connect the appropriate one of the ports 97, 98 to discharge when the other port is subjected to the pump pressure. The solenoid is operated by means of a timer or by means of a proximity sensor on the main pistons 27, 28 or by a pressure-operated switch 105, as indicated diagrammatically in FIG. 5, this switch responding to the increase in pressure at the outlet of the pump 20 at the end of the stroke serving to effect an electrical connection energising the solenoid to reverse the spool valve. The spool valve may be moved in one direction or the other electrically, e.g. by providing separate solenoids for each direction of movement or the movement in one direction may be effected by the solenoid and movement in the opposite direction by a spring indicated diagrammatically at 106.
Particularly with a large reverse osmosis installation having a plurality of cylinders 25, 26 which are to be operated in a timed sequence, it may be convenient to use a timing device for operating the associated spool valve for each double cylinder device. Such an arrangement may also be used in a radial system, as previously described, having three or more cylinders operated in sequence.
FIG. 6 illustrates another construction in which the rise in pressure of the water from the pump 20 at the end of the stroke is utilized to effect operation of a spool valve controlling the piloted valves. In FIG. 6, the spool valve 90 and the piloted valves 80, 83 are similar to those described with reference to FIG. 5 and the same reference characters are used to indicate corresponding components. In FIG. 6 however reversing of the spool valve 90 is effected by means of a reversing mechanism comprising a fixed cylinder 110 having a piston 111 which is urged in one direction by means of a spring 112. The piston is movable in the opposite direction under the influence of the pressure from the pump 20 via line 113. The spring 112 is arranged so that normally it holds the piston 111 at the right-hand end of the cylinder as seen in the drawing when the pump 20 is providing the normal output pressure which is, in this particular embodiment, 60 p.s.i. As previously explained, at the end of the stroke of the main pistons in the cylinders 25, 26, the output pressure from the pump 20 will rise. This output pressure is applied to the piston 111 and overcomes the spring force to drive the piston to the left.
The piston carries a flexible needle 120, which is typically a stainless steel wire, stiffened along part of its length remote from the piston 111, this stiffening being effected by a thin bore metal tube 121 surrounding the wire. The wire is terminated in a small ball or loop 123. The needle is thus flexible only in the region close to the piston 111. This needle co-operates with a cam 130 having cam surfaces in the form of a letter W, the surfaces being curved and having a central upstanding part 131 and outer upstanding parts 132, 133. The cam is pivoted on a fixed pivot 134 and is rotatable through 45° in either direction so that it is movable into either one or other of the positions shown in FIGS. 6a and 6b. FIG. 6 shows the cam in a neutral position. In normal operation it is, as explained below, forced into one or other of the positions shown in FIG. 6a or 6b. This cam has pivoted thereto at 138, a connecting rod 139 for effecting linear movement of the operating member 104 for the spool valve 90.
At the end of an operating stroke of the pistons in the main cylinders 25, 26, the pressure at the output of the pump 20 rises and drives the needle 120 forwardly. This will engage one side or other of the central projection 131 and will ride around the curved cam surface so as to push that end of the cam 130 to the left in the drawing. If this is the upper part of the cam, then the spool operating member is drawn to the right, the cam being set thus to the position shown in FIG. 6a. If on the other hand the needle engages the lower part of the cam, it will push the lower part of the cam to the left and will force the operating member of the spool to the left with the cam being set as shown in FIG. 6b.
It will be immediately apparent from FIGS. 6a and 6b that, as soon as the cam has been set on one side by an operating stroke of the needle, it is positioned so that the needle will select the opposite direction for the next stroke. Thus the system operates to reverse the spool valve 90 each time the pressure in the output of the pump 20 rises.
It will be noted that the alternate reversing thus achieved happens at the end of each stroke so that the pressure in the feed system 21, 22 will not fall until the controlled valves 80, 83 have changed their position and thus permitted the main pistons 27, 28 to reverse their function and commence movement in the opposite direction. At the end of the new stroke, the pistons 27, 28 will again stop, pressure will rise and overcome the spring force of spring 112 to operate the mechanism again to engage the new section of the cam 130 and rotate the cam back.
The spool valve 90 is preferably arranged so that the pressure port 96 of the spool does not admit pressure to the chambers on one or other side of the central spool 92 until the outer spools 91, 93 have covered or uncovered the ports 97, 98 leading to the piloted valves 80, 83. This ensures that O-rings or other seals on the spools are under zero pressure as they pass the ports in the walls of these chambers. Each port 97, 98 is arranged as a number of small apertures extending around the circumference of the body of the valve in each porting position. Thus very small holes can be used so minimizing the intrusion of such O-rings into these holes. The centre port 96 is under pressure from the pump 20 all the time and thus intrusion into the holes providing the centre port is impossible. The outermost ports leading to discharge are never under pressure and so need not be protected in this way. | In apparatus for the reverse osmosis purification of water or other fluid in a module containing a membrane, the water is forced into the module under pressure using two piston-cylinder assemblies mechanically interconnected with the pressurized fluid from the module applied to the rear face of the piston which, from its front face, is driving water into the module, a low pressure continuously operating pump providing a low pressure on the other piston to supply the necessary extra pressure. Valve means automatically reverse the functions of the two cylinders at each end of each stroke. | 8 |
[0001] The present invention relates to odor control in disposable, absorbent articles using phosphorous-containing compounds.
BACKGROUND OF THE INVENTION
[0002] A variety of additives are currently used in disposable, absorbent articles for reducing or controlling malodors associated with body exudates. It is known that many malodors associated with body exudates are due to the microbial decomposition of lipids, particularly triglycerides and phospholipids, into fatty acids. U.S. Pat. No. 4,356,190, for example, discloses the use of compounds such as EDTA to inhibit the formation of such fatty acids. Other materials as diverse as zeolites, baking soda, compounds containing active carbon, and charcoal have also been employed in absorbent articles for odor control. See for instance, U.S. Pat. No. 5,306,487.
[0003] U.S. Pat. No. 5,567,231 relates to a deodorant comprising 5 to 100 weight % of a calcium phosphate compound having a Ca/P molar ratio of 0.8 to 2.0. Materials such as filter sheets incorporating such a compound are taught to have improved adsoptivity to a side variety of substances, such as oil-soluble substances, odor substances, viruses, etc.
[0004] Applicant has now discovered that malodors associated with the microbial decomposition of lipids in body exudates absorbent articles can be reduced or eliminated by incorporating into such absorbent articles an odor control additive comprising at least one water soluble salt containing an anion selected from the group consisting of P 2 O 7 4− , P 3 O 9 3− , and P 3 O 10 5− . Alternatively, such odor control additive may comprise a water soluble compound of the formula (APO 3 ) n , wherein A is a Group 1 element and n is 4 to 50.
SUMMARY OF THE INVENTION
[0005] The present invention provides a disposable, absorbent article comprising a liquid permeable cover and an absorbent core, wherein said absorbent article contains an odor control additive comprising at least one water soluble salt containing an anion selected from the group consisting of P 2 O 7 4− ,P 3 O 9 3− , and P 3 O 10 5− .
[0006] The present invention also provides a disposable, absorbent article comprising a liquid permeable cover and an absorbent core, wherein said absorbent article contains an odor control additive comprising a water soluble compound of the formula (APO 3 ) n , wherein A is a Group 1 element and n is 4 to 50.
[0007] The present invention further provides methods of reducing malodors in a disposable, absorbent article, comprising incorporating into the absorbent article an odor control additive comprising at least one water soluble salt containing an anion selected from the group consisting of P 2 O 7 4− , P 3 O 9 3− , and P 3 O 10 5 , or a water soluble compound of the formula (APO 3 ) n , wherein A is a Group 1 element and n is 4 to 50.
DETAILED DESCRIPTION OF THE INVENTION
[0008] The absorbent article may for example be a sanitary napkin, pantiliner, diaper, incontinence pad, interlabial article, tampon or other intravaginal device, shoe liner, or other similar product for absorbing exudates from the body, such as menses, urine, feces, or sweat. Preferably, the absorbent article is a sanitary napkin or a pantiliner. Such sanitary napkin or pantiliner may have an approximately rectangular, oval, dogbone, or peanut shape. Depending on the nature of the absorbent article, its size may vary. For example, sanitary napkins typically have a caliper of about 1.4 to about 5 mm, a length of about 3 to about 16 inches, and a width of about 1 to about 5 inches. Pantiliners typically have a caliper of less than about 0.2 inches, a length of less than about 8 inches, and a width of less than about 3 inches.
[0009] The absorbent article generally comprises in sequence from its body-facing surface to its garment-facing surface liquid permeable cover, an absorbent core, and optionally a backsheet. The cover of the absorbent article may be formed from any fluid pervious material that is comfortable against the skin and permits fluid to penetrate to the absorbent core, which retains the fluid. The cover should retain little or no fluid to provide a relatively dry surface, since its external surface forms the body-facing surface of the article. A variety of materials are known for preparing covers, and any of these may be used. For instance, the cover may be a fibrous non-woven fabric made of fibers or filaments of polymers such as polyethylene, polypropylene, polyester, or cellulose. Alternatively, the cover may be formed from an apertured polymeric film. The thickness of the cover may vary from approximately 0.001 to 0.062 inch, depending on the material chosen.
[0010] Generally, the cover is a single sheet of material having a width sufficient to form the body-facing surface of the article. The cover may be the same length, or optionally longer than the absorbent core so as to form transverse ends. Such transverse ends may be sealed with other layers to fully enclose the absorbent core.
[0011] The absorbent core may be comprised of a loosely associated absorbent hydrophilic material such as cellulose fibers, including wood pulp, regenerated cellulose fibers or cotton fibers, or other absorbent materials generally known in the art, including acrylic fibers, polyvinyl alcohol fibers, peat moss and superabsorbent polymers.
[0012] The absorbent article may further comprise a backsheet that is substantially or completely impermeable to liquids, the exterior of which forms the garment-facing surface of the article. The backsheet may comprise any thin, flexible, body fluid impermeable material such as a polymeric film, for example, polyethylene, polypropylene, or cellophane. Alternatively, the backsheet may be a normally fluid permeable material that has been treated to be impermeable, such as impregnated fluid repellent paper or non-woven fabric material, or a flexible foam, such as polyurethane or cross-linked polyethylene. The thickness of the backsheet when formed from a polymeric film typically is about 0.001 to 0.002 inch. A variety of materials are known in the art for use as backsheet, and any of these may be used.
[0013] Generally, the backsheet is a single sheet of material having a width sufficient to form the garment-facing surface of the absorbent article. The backsheet may extend around the sides of the absorbent core in a C-shaped configuration with the portions of the backsheet adjacent its longitudinal edges extending upwardly from the garment-facing surface toward the body-facing surface of the article. Preferably the backsheet is breathable, i.e., a film that is a barrier to liquids but permits gases to transpire. Materials for this purpose include microporous films in which microporosity is created by stretching an oriented film. Single or multiple layers of permeable films, fabrics, and combinations thereof that provide a tortuous path, and/or whose surface characteristics provide a liquid surface repellent to the penetration of liquids may also be used to provide a breathable backsheet.
[0014] The absorbent article may be applied to the crotch of underpants by placing the garment-facing surface of the absorbent article against the inside surface of the crotch of the underpants. Strips of pressure sensitive adhesive may be applied to the garment-facing surface of the absorbent article to help maintain it in place. As used herein, the term “pressure-sensitive adhesive” refers to any releasable adhesive or releasable tenacious means. Suitable pressure sensitive adhesives include for example water-based adhesives such as acrylate adhesives. Alternatively, the adhesive may comprise “hot melt” rubber adhesives or two-sided adhesive tape.
[0015] A paper release strip that has been coated on one side may be applied to protect the strips of adhesive prior to use. The coating, for example silicone, reduces adherence of the coated side of the release strip to the adhesive. The release strip can be formed from any suitable sheet-like material which, when coated, adheres with sufficient tenacity to the adhesive to remain in place prior to use but can be readily removed when the absorbent article is to be used.
[0016] The absorbent article may comprise other known materials, layers, and additives, such as transfer layers, foam layers, net-like layers, perfumes, medicaments, moisturizers, and the like, many examples of which are known in the art. The absorbent article can optionally be embossed with decorative designs using conventional techniques.
[0017] According to the invention, the absorbent article contains one or more odor control additives comprising one or more phosphorous-containing compounds of the following types: 1) water soluble salts containing an anion selected from the group consisting of P 2 O 7 4− , and P 3 O 9 3− , and P 3 O 10 5− ; and 2) water soluble compounds of the formula (APO 3 ) n , wherein A is a Group 1 element and n is 4 to 50. The water soluble salts containing an anion selected from the group consisting of P 2 O 7 4− , P 3 O 9 3− , and P 3 O 10 5− preferably comprise a cation containing a Group 1 element or ammonium. More preferably such water soluble salts comprise a cation containing sodium. Particularly preferred water soluble salts are tetrasodium pyrophosphate and pentasodium triphosphate.
[0018] In water soluble compounds of the formula (APO 3 ) n , A is preferably sodium and n is preferably 4 to 50. More preferably n is 15 to 20.
[0019] In addition to the above phosphorous-containing compounds, the odor control additive may comprise other ingredients such as EDTA, zeolites, or other known odor control agents.
[0020] The odor control additive may by incorporated into or onto the cover, absorbent core, or backsheet of the absorbent article, or combinations thereof. Alternatively, if the absorbent article comprises additional layers, such as a transfer layer, etc., the odor control additive may be incorporated into or onto such additional layers. Preferably, the cover of the absorbent article comprises the odor control additive, so the odor control additive is in close proximity to the body and the site of initial discharge of body exudates.
[0021] The physical form of the odor control additive is not critical to the invention. The odor control additive may be used in the form of powder or a liquid solution. It may also be incorporated into one or more adhesives used in the absorbent article. See for example U.S. Pat. No. 4,186,743, which relates to the use of microcapsules containing a deodorant material that are contained in the adhesive element of a sanitary napkin.
[0022] The amount of odor control additive used in the absorbent article depends on the size and nature of the layer it is being incorporated into and the absorbent article. Typically, the amount of odor control additive is used is to provide about 0.01 to about 1 gram of phosphorous-containing compound per square inch of layer. Preferably, about 0.02 to about 0.50 gram of phosphorous-containing compound per square inch of layer should be present in the absorbent article. However, even smaller amounts of odor control additive are capable of reducing malodor levels in the absorbent article.
[0023] It is believed the odor control additive helps to reduce malodors by interfering with the decomposition of lipids by bacteria into fatty acids in body exuadates. The odor control additive also has a somewhat basic pH and can therefore neutralize the fatty acids that are produced.
[0024] Advantageously, the phosphorous-containing compounds contained in the odor control additive are safe for contact with humans. They are also relatively less harmful to the environment than many other types of compounds. They are also less expensive than EDTA for example.
[0025] The following example is intended to illustrate the invention further.
EXAMPLE
[0026] A pantiliner is made according to the invention as follows. The pantiliner comprises a cover, an absorbent core, and a backsheet. The absorbent core is made of airlaid pulp. It is 35 mm wide, 150 mm long and 1.2 mm thick. The absorbent core also contains 0.1 gram of tetrasodium pyrophosphate as an odor control additive. The tetrasodium pyrophosphate is used in the form of a powder, and is evenly dispersed over the absorbent core. | A method of odor control in disposable, absorbent articles is provided using odor control additives comprising phosphorous-containing compounds. | 0 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to a latch and method of mounting same. More particularly but not exclusively the latch and method of mounting is intended for use with sliding and hung window systems.
[0002] Typically latches for sliding and hung window systems are surface mounted. Thus they are readily visible on the window and can therefore adversely impact on the aesthetic appeal of the window installation.
[0003] Surface mounting latches are normally attached to the window by use of mechanical fasteners. In time the latch can become “loose” on the window due to loosing of the mechanical fastener or in extreme cases the opening in the window extrusion in which the fastener is fitted can become oversized and the latch can become separated from the window. Generally this oversizing of the opening results from the fastener initially becoming loose.
SUMMARY OF THE INVENTION
[0004] It is an object of the present invention to provide a latch which is in a large part concealed within a window extrusion.
[0005] It is a further object of the present invention to provide a latch which is of such construction that no fixing screws or other mechanical fasteners are required for installation of the latch in a window system.
[0006] Broadly according to one aspect of the present invention there is provided a latch device including a body, a latch element movably mounted within the body and movable between a latching position and non-latching position, moving mechanism for moving the latch element between said latching and non-latching positions, the body having retaining elements to retain the body when installed through an opening and into a window extrusion.
[0007] In a preferred form of the invention the latch device further includes an externally accessible operating slide element which is engageable with said moving mechanism. The slide element can be slidingly engaged with a mounting member which is mountable in a snap lock arrangement in an opening in a window extrusion. The coupling between the slide element and the moving means can be formed by inter-engagement of an elongate member in an aperture.
[0008] According to a preferred form of the invention the moving mechanism includes a sub-housing slidingly located in the body, the latch element being pivotal about an axis fixed relative to the body and coupled to the sub-housing such that sliding movement of the sub-housing translates into a pivotal movement of the latch element.
[0009] Preferably a biasing means is coupled between the body and the sub-housing. The latch element is preferably a hook tongue.
[0010] According to a second broad aspect of the invention there is provided a method of mounting a latch device in an extruded window element the method including the steps of forming apertures in opposing spaced apart walls of the window element, inserting through one aperture in a snap lock fitting a latch body of the latch device so that the body is substantially located within the extruded element and installing in the other aperture operating furniture which when installed inter-engages with latch moving means of the latch body.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] In the following more detailed description of a preferred embodiment of the invention reference will be made to the accompanying drawings in which:
[0012] [0012]FIG. 1 is a perspective illustration of the latch when in the “locked” position and with a cover of the housing removed for better illustration,
[0013] [0013]FIG. 2 is a further perspective view of the latch as shown in FIG. 1 but with the cover installed and without the operating “furniture”,
[0014] [0014]FIG. 3 is a further perspective view of the arrangement shown in FIG. 2 but with the cover removed,
[0015] [0015]FIG. 4 is a view similar to FIG. 3 but with the latch in the unlocked position,
[0016] [0016]FIG. 5 is a perspective view in disassembled form of the operating furniture,
[0017] [0017]FIG. 6 is a further perspective view of the disassembled operating furniture,
[0018] [0018]FIG. 7 is a plan view of the housing of the latch,
[0019] [0019]FIG. 8 is a face elevation view of the housing shown in FIG. 7, and
[0020] [0020]FIG. 9 is an end elevation view of the housing shown in FIGS. 7 and 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] The latch according to the preferred embodiment shown in the drawings includes a main housing 10 , a lock beak 11 , a sub-housing 12 and operating furniture 13 . The operating furniture 13 includes a body 14 and a slide 15 with an integral gripping projection 16 . These elements of the construction of the latch are shown in FIG. 1 where a cover 17 (see FIG. 2) of the housing 10 has been removed for the purposes of illustration.
[0022] The housing 10 has an integral faceplate 18 with an opening 19 through which the hook beak can move from its retracted (unlatched) position to the projecting (latched or locked) position.
[0023] Disposed parallel to but spaced from faceplate 18 is a wall 20 which like faceplate 18 extends at right angles to the floor 23 of the housing 10 . This wall 20 also has an opening 21 through which projects a stub shaft 22 from sub-housing 12 . The slot 21 is of sufficient length to accommodate the movement of the stub shaft 22 during sliding movement of the sub-housing 12 in housing 10 as will hereinafter be described.
[0024] Extending between cover plate 18 and walls 20 and also at right angles to the floor 23 are end walls 24 . These end walls 24 kink inwardly toward the faceplate 18 to form a recess 25 . A resilient arm 26 extending from wall 24 is located adjacent each recess 25 . The arm 26 , which is integrally formed with wall 24 , extends outwardly at an angle to the plane of wall 24 and is slightly cranked at its distal end 27 .
[0025] Projecting from the floor 23 of the housing 10 is a spigot 28 . This spigot extends through a pair of aligned slots 29 in the respective spaced apart and parallel walls 30 of the sub-housing 12 . The hook beak 11 has an opening 31 in the main body 32 thereof and this is journal onto spigot 28 . The hook beak 11 can thus rotate about the axis of the spigot 28 .
[0026] Coupled to a flange 33 extending from an end wall 34 of the sub-housing 12 is a spring 35 . The other end of the spring 35 is coupled to a pin 36 which is mounted with the housing 10 by projecting upwardly from floor 23 .
[0027] The sub-housing 12 is aligned for longitudinal sliding movement within the main housing 10 by an abutment 37 which extends inwardly from the inside surface of wall 20 . This abutment 37 engages with the sidewall 38 of sub-housing 12 . A plurality of projections 39 extend from one of the walls 30 of the sub-housing 12 and slidingly engage with the inside surface of faceplate 18 . Accordingly, when the cover 17 is in place the sub-housing 12 can slidingly move within the housing 10 between the positions shown in FIGS. 3 and 4 which correspond with the latching position and in the unlatched position.
[0028] Extending from each of the walls 30 are a pair of oppositely disposed spigots 40 . These slidingly engage in a slot 41 formed in the main body 32 of the hook beak 11 . The slot 41 has an angled end 41 a . It is in this end 41 a that the spigot 40 resides when the hook beak 11 is in the latched position as shown in FIGS. 1 - 3 .
[0029] Referring to FIG. 4 the latch is moved from the unlatched position to the latched position by moving sub-shaft 22 in the direction of arrow A. This causes the sub-housing 12 to slide within the housing 10 . This sliding movement results in the spigots 40 sliding along slot 41 which causes the hook beak 11 to rotate about the axis of spigot 28 . At the end of the travel the spigots 40 move into portion 41 a of the slot.
[0030] Because end portion 41 a is not aligned with the main length of the slot 41 it is not possible for someone wishing to gain unauthorised access to manipulate the tongue in such a way as to apply a force which would cause the hook beak to rotate about the axis of spigot 28 . Consequently, there is an inbuilt dead latching function achieved when the sub-housing 12 has moved to its fullest extent -in the latching direction A. This means that the hook beak 11 when in the deadlocked position can only be moved by moving the stub shaft 22 in a direction opposition to arrow A i.e. toward the unlatching position.
[0031] It will be noted that the spring 35 applies a spring bias to the sub-housing 12 when in the unlatched position. This ensures that the hook beak 11 remains in the retracted position.
[0032] The operating furniture consists of a body 11 which forms a recessed area in which the slide 15 is movable. The floor 43 of the recessed area 42 includes an elongate slot 44 .
[0033] Projecting from the underside of slide 15 is a tapered projection 45 which has a bore or opening 46 within which the end of the stub shaft 22 can engage. Where the tapered projection 45 extends from the main body of the slide 15 a pair of opposed slots 47 are formed. Thus to assemble the slide 15 with the body 14 the tapered projection 45 is forced through slot 44 until the long edges of the slot 44 slidingly engage in slots 47 . Therefore, effectively slide 15 is fitted in a “snap lock” fitting arrangement with body 14 .
[0034] On the external of the surfaces of the long walls 48 of wall 49 are a pair of spaced apart ramps 50 . The ramps 50 are spaced from the shoulder 51 formed by rim 52 of the body 14 . The spacing is about the same as the thickness of material surrounding a shaped opening formed in the window extrusion into which the well 49 is inserted during installation of the latch. Thus, once again a snap-lock fitting is used when installing the body 14 in the opening formed in the window extrusion.
[0035] Similarly, an opening is formed in the window extrusion opposite that in which the body 14 of the operating furniture is inserted. This opening is sized so as to accommodate the length and height of the body 10 but is less than the overall dimensions of the faceplate 18 . The body 10 is thus inserted through this opening and as it does so the fingers 26 move resiliently into the recesses 25 but spring back when the housing is pushed fully home into the window extrusion thereby capturing the housing 10 within the extrusion. Generally the housing 10 will be installed in the window extrusion before the operating furniture so that the slide 15 can be correctly aligned for engagement of the sub-shaft 22 through opening 46 in the tapered projection 45 .
[0036] No fixing screws are therefore required in either assembly of the latch or its installation. As described above the operating furniture and the latch body 10 are simply snap-locked into place in the window extrusion. This results in the mechanism of the latch essentially being located within the window extrusion while the only visible feature will be the rim portion and slide within the recess 43 visible. However, these features can, as illustrated in the drawings, be made aesthetically pleasing in appearance and will, therefore, not detract from the visual appearance of the window.
[0037] Likewise, the latch itself can be assembled without the need for any fixing screws. By slightly parting the walls 30 of the sub-housing 12 sufficient clearances is provided for insulation of the hook beak 11 . Upon release of the walls 30 the spigots 40 engage from either side into slot 41 . The sub-housing 12 with installed hook beak 11 can then be placed in the housing so that the opening 31 in the hook beak body 32 engages over spigot 28 . Once the spring 36 has been installed the cover 17 can be positioned and put in place and retained by say dowels formed integrally with the cover 17 interference fitting in openings 53 in the floor 23 of the housing 10 .
[0038] The present invention thus provides a latch for sliding and hung window systems. The main latch mechanism is concealed within the window extrusion and fits in a snap-lock type fitting. Likewise, the operating furniture is in part recessed into the window extrusion and snap-locks in place. The only readily visible part of the overall latch assembly can, therefore, be made unobtrusive and aesthetically pleasing in appearance. | A latch device intended for use with sliding and hung window systems. The latch device has a body ( 10 ) and a latch element ( 11 ) which is moveable between a latching position where it projects from the body ( 10 ) and a non-latching position where it is retracted into the body. A slide element ( 15 ) in a body ( 14 ) is coupled to a movable sub-housing ( 12 ) so that movement of the sub-housing ( 12 ) by the slide element ( 15 ) causes the latch element ( 11 ) to be moved. The body ( 10 ) is insertable into an opening in a window section and snap locks in place by the action of fingers ( 27 ) and face plate ( 18 ) acting on opposite sides of the window section adjacent the opening. The latch device can thus be fixed into a window section without any additional fasteners. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a national stage of International Application No. PCT/EP2009/001059 filed Feb. 16, 2009, the disclosures of which are incorporated herein by reference, and which claimed priority to German Patent Application No. 10 2008 010 704.2 filed Feb. 22, 2008, the disclosures of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The invention relates to a vehicle brake system. In particular, the invention relates to a coordination of the functions of hydraulic brake boosting and electronic brake force distribution.
[0003] Vehicles that have brake systems actuated hydraulically or electrohydraulically conventionally comprise a plurality of mutually independent brake circuits. The use of a plurality of mutually independent brake circuits serves the purpose of redundancy, so that it is still possible to brake the vehicle even if one of the brake circuits should be unable to function. Furthermore, a braking response of the vehicle may be influenced in that during a braking operation the brake circuits are actuated differently. Especially in the case of heavy cars and lorries it is customary to provide one brake circuit for a front axle and another brake circuit for a rear axle. Such a brake circuit split is also known as a “black-and-white split” or “front/rear split brake circuit”.
[0004] In many motor vehicles actuation of the brake system is made easier for the driver by means of brake force boosting. In this case, the force generated by the driver by means of an actuation of the brake pedal is transmitted to a master cylinder and additionally increased by a specific factor by means of a brake booster. This assistance makes it easier for the driver to achieve a high brake pressure and hence a high deceleration effect, while as a result of the direct introduction of the hydraulic pressure generated by the driver into the brake circuit a braking of the motor vehicle itself remains possible even in the event of failure of the brake boosting.
[0005] The additional force needed to boost the brake force summoned up by the driver is drawn for example by a vacuum brake booster from a vacuum that is conventionally generated by a drive motor of the motor vehicle in a vacuum accumulator. In this case, there are a number of situations, in which such a brake booster is not, or is insufficiently available to assist a braking operation to a required extent. For example, the vacuum accumulator gradually empties while the drive motor is not running. After starting of the drive motor the vacuum accumulator therefore first has to be re-evacuated, which takes a specific time, during which the capacity of the brake booster is not fully deployable. In another example, the motor vehicle is exposed to a low external air pressure, for example at high altitude, so that a boosting effect of the vacuum brake booster because of the slight difference between the vacuum and the air pressure acting from outside may likewise be lower than that requested by the driver.
[0006] In order to bridge such situations of insufficient brake boosting, in the background art it is known to provide a hydraulic pump that is designed, where necessary, to generate an assisting hydraulic pressure in a brake circuit (hydraulic brake boost, HBB). A correspondingly powerful design of the hydraulic pump additionally allows the vacuum brake booster to be of smaller dimensions, thereby leading to reduced costs.
[0007] If the driver of a vehicle requests a very high brake pressure, then because of the dynamic axle-load distribution of the vehicle during braking a braking effect that may be generated via the front axle is greater than that of a rear axle. Wheels of the rear axle therefore tend to have a higher wheel slip than wheels of the front axle. An undesirable reduction of the directional stability of the vehicle that results from an excessive wheel slip at wheels of the rear axle may be counteracted by an electronic brake force distribution (EBD) becoming active at the rear axle. The EBD reduces the brake pressure of the rear axle brakes by means of an actuation of suitable valves in the rear-axle brake circuit, with the result that the wheel slip at the rear axle is limited.
[0008] In certain operating situations the hydraulic brake boosting attempts to increase a brake pressure in a rear axle brake, while the electronic brake force distribution however does not allow the brake pressure generated by the hydraulic pump to reach the brakes. As a result, the HBB system and the EBD system work against one another in these situations.
[0009] The underlying problem of the invention is therefore to indicate a method of operating a brake system that avoids the previously described drawbacks.
BRIEF SUMMARY OF THE INVENTION
[0010] According to a first aspect, a method of effecting electronic brake distribution in a vehicle brake system equipped with hydraulic brake boosting, wherein the hydraulic brake boosting is designed to assist the build-up of a brake pressure requested by a driver, comprises the steps of detecting a state requiring an electronic brake force distribution and of limiting the brake pressure generation of the hydraulic brake boosting in accordance with the electronic brake force distribution. The limiting of the brake pressure generation may comprise the build-up of the brake pressure up to at most a limit value or alternatively the lowering of a brake pressure down to or below the limit value.
[0011] The hydraulic brake boosting may be effected by means of an HBB system and the electronic brake force distribution may be effected by means of an EBD system. The detecting of a driving- or vehicle state that requires an electronic brake force distribution may comprise determining at least one of the following variables: a laden state, an inclination in a longitudinal or transverse direction, a yaw rate, a wheel slip at a rear axle, a wheel slip at a front axle, a vehicle velocity, a rotational speed of a wheel, and an angle of rotation of a steering wheel of the vehicle.
[0012] The hydraulic brake boosting may comprise electrical actuation of a hydraulic pump that is integrated into the vehicle brake system. In particular, the limiting of the brake pressure build-up may be effected by electrical actuation of the hydraulic pump.
[0013] In an embodiment, the hydraulic pump is driven by an electric motor and an electric power consumed by the electric motor is adjusted in a suitable manner. This may be effected for example by influencing an electric current consumed by the electric motor, a voltage across the electric motor and/or a pulse/pause ratio of pulse width modulation that controls the electric motor. In another embodiment, in the course of actuation a delivery response of the hydraulic pump may be influenced by means of a final controlling element, for example by electrically influencing the transmission response of a force-transmitting device between a drive and the hydraulic pump. This control may be effected likewise by means of influencing a current, a voltage and/or a pulse/pause ratio of pulse width modulation.
[0014] The electrical actuation of the hydraulic pump for the hydraulic brake boosting may be effected upon attainment or upon immediately impending attainment of a maximum gain of a brake booster that is integrated into the vehicle brake system. The brake booster may be a vacuum brake booster or a pneumatic brake booster. The maximum gain indicates the operating state of a brake booster, in which the maximum boosting effect is achieved. The maximum gain may vary as a function of various parameters (for example the maximum vacuum that may just be generated).
[0015] The hydraulic brake boosting may comprise an electrical actuation of a valve that hydraulically separates a high-pressure side of the hydraulic pump from a driver-operated master cylinder. The actuation may be effected for example in such a way that a brake pressure generated by the hydraulic pump is not diverted into the master cylinder (and optionally from there into a hydraulic fluid reservoir). A second valve may be hydraulically connected in parallel to the valve, wherein the second valve exercises a pressure-limiting function. This means that the second valve opens automatically as soon as a preset pressure difference at its two ports is exceeded. With the aid of such a pressure-limiting valve, damage as a result of overloading of parts of the brake system may be avoided.
[0016] The hydraulic brake boosting may further comprise electrical actuation of a valve that hydraulically connects a low-pressure side of the hydraulic pump to a driver-operable master cylinder. As a master cylinder is conventionally connected to a hydraulic fluid reservoir, it is possible in this way to ensure for example that the hydraulic pump may take in sufficient hydraulic fluid.
[0017] The limiting of the brake pressure build-up of the hydraulic brake boosting may comprise the generating of a lower assisting brake pressure on the part of the hydraulic pump in comparison to a state not requiring an electronic brake force distribution. For example, in a first vehicle state that does not require an electronic brake boosting, the brake pressure build-up of the hydraulic brake force distribution may be a function only of a brake force summoned up or requested by the driver of the vehicle. In this case, there may be a linear or some other relationship between the assisting brake pressure generated by the hydraulic brake boosting and the brake force initiated by the driver. There may further be a linear or some other relationship between the brake pressure requested by the driver and the brake force exerted by him. In a second vehicle state that requires an electronic brake force distribution, the generation of the assisting brake pressure supplied by the hydraulic brake boosting may be limited to a value that is lower than a corresponding value of an assisting brake pressure in the first vehicle state. This lower value may correspond to the value that would be generated in the case of an electronic brake force distribution without hydraulic brake boosting.
[0018] In the course of the electronic brake force distribution, brake pressures that differ from axle to axle may be adjusted, wherein the limiting of the brake pressure build-up of the hydraulic brake boosting is effected at least at one vehicle rear axle or at a plurality of vehicle rear axles. For example, there may be associated with one or more vehicle rear axles an individual brake circuit, in which the brake pressure build-up, controlled by the electronic brake force distribution, is limited. In particular, in a vehicle having two separate brake circuits a first brake circuit may be associated with a front axle and a second brake circuit with a rear axle of the vehicle and the limiting of the brake pressure build-up may relate only to the second brake circuit.
[0019] The detecting of a state requiring an electronic brake force distribution may comprise detecting a wheel slip that differs from axle to axle. A wheel slip may be determined by processing a rotational speed of a wheel and a vehicle velocity. Particularly if at least one rear wheel has a higher wheel slip than a front wheel, it is possible to infer a state requiring an electronic brake force distribution.
[0020] The electronic brake force distribution may supply the hydraulic brake boosting with a pressure signal, which below a limit pressure corresponds to a brake pressure in a driver-operable master cylinder. If the limit pressure is reached, then the pressure signal corresponds to the limit pressure. The limit pressure in this case is a brake pressure that guarantees directional stability of the vehicle. In this way, a conventional hydraulic brake boosting may be used according to the invention in interaction with an electronic brake force distribution without requiring any further modifications to the hydraulic brake boosting.
[0021] According to a second aspect, a computer program product comprising program code means is provided for performing the previously described method when the computer program product runs on a processing unit (for example a control unit). Such a processing unit may control the functions of the EBD and the HBB. Further braking-related control systems such as ABS and ESP may additionally run on the processing unit.
[0022] The computer program product may be stored on a computer-readable data carrier. For example, the computer program product may be stored on a mobile data carrier, such as for example a diskette, a hard disk, a CD or DVD, or on a fixed data carrier, such as for example a semiconductor memory (say, a RAM, ROM, EPROM, EPROM, NOVRAM or FLASH).
[0023] According to a third aspect, a vehicle brake system is provided, comprising a hydraulic brake booster that is designed to assist the build-up of a brake pressure requested by a driver as well as an electronic brake force distributor comprising a detector for detecting a state requiring an electronic brake force distribution and a limiter for limiting the brake pressure build-up of the hydraulic brake boosting in accordance with the electronic brake force distribution.
[0024] The detector may acquire for example at least one of the following parameters: a laden state, a velocity, an inclination of the vehicle in a longitudinal- or transverse direction, a yaw rate, a wheel slip at a rear axle, a wheel slip at a front axle, a vehicle velocity, a rotational speed of a wheel, and an angle of rotation of a steering wheel of the vehicle.
[0025] The hydraulic brake booster may be designed to actuate a hydraulic pump. The hydraulic pump may bring about a positive hydraulic pressure difference between a hydraulic line leading to wheel brakes and a driver-operable master cylinder. In such a situation, the limiter may be realized by means of an electronic actuating device for the hydraulic pump.
[0026] The vehicle brake system may comprise a valve that is adapted to be actuated in order to hydraulically separate a high-pressure side of the hydraulic pump from a driver-operable master cylinder. This valve may be electrically controllable.
[0027] The vehicle brake system may further comprise a valve that is adapted to be electrically activated in order to hydraulically connect a low-pressure side of the hydraulic pump to a driver-operable master cylinder. If the master cylinder is in turn connected to a hydraulic fluid reservoir, the hydraulic pump may take in hydraulic fluid in this way. Alternatively or in addition thereto, a hydraulic fluid delivered by the hydraulic pump may also come from another source, for example from an accumulator. The control of this valve may likewise be effected electrically.
[0028] The hydraulic brake booster may comprise a first control unit and the electronic brake force distributor may comprise a second control unit, wherein between the first control unit and the second control unit an interface may be provided for communicating brake pressure limiting commands from the second control unit to the first control unit. The interface may be for example an electrical interface or a data interface. The limiting commands may be in the form of analogue or digital data or signals.
[0029] Alternatively, control modules of the hydraulic brake booster and of the electronic brake force distributor may be different functional modules within a common control unit. In one implementation, each of the functional modules may be a computer program that runs in the control unit.
[0030] Other advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments, when read in light of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 a schematic representation of a brake system with hydraulic brake boosting;
[0032] FIG. 2 a functional overview of a brake system with hydraulic brake boosting and electronic brake force distribution;
[0033] FIG. 3 a schematic flowchart of a method of building up a brake pressure; and
[0034] FIG. 4 brake pressure characteristics of wheel brakes at a front- and a rear axle of a vehicle.
DETAILED DESCRIPTION OF THE INVENTION
[0035] FIG. 1 shows in a schematic representation a hydraulic brake system 100 according to an embodiment. The brake system 100 operates by means of a hydraulic fluid that is stored in part in a container 111 serving as a reservoir. Brake pressure, which arises by pressurizing the hydraulic fluid, is generated by means of a master cylinder 112 that is to be operated by the driver by means of a pedal 113 , wherein the force F initiated by the driver is boosted—for example by means of a vacuum—by a brake booster 114 .
[0036] From the master cylinder 112 a first brake circuit I. and a second brake circuit II. are supplied, wherein with each brake circuit two wheel brakes are associated. As the brake circuits I. and II. may be substantially identical in construction, here only the first brake circuit I. that supplies two wheel brakes 150 and 160 is represented in detail. Depending on which wheel brakes of the vehicle are supplied by which brake circuit, the result is either a front-/rear axle split (also: “black-and-white split” or “front/rear split brake circuit”), i.e. the one brake circuit supplies the wheel brakes of the front axle and the other brake circuit supplies the wheel brakes of the rear axle, or a diagonal split (also: “diagonal split brake circuit”), i.e. each brake circuit supplies the wheel brake of a front wheel and the wheel brake of the diagonally opposite rear wheel. In the following it is assumed that there is a black-and-white split and that the wheel brakes 150 and 160 act upon wheels of a rear axle of the vehicle.
[0037] The hydraulic connection from the master cylinder 112 to the wheel brakes 150 and 160 is determined by electromagnetically actuated 2/2-way valves 151 , 152 , 161 , 162 , 171 and 172 , which in the inoperative, i.e. electrically non-actuated state occupy the basic positions represented in FIG. 1 . Here in particular this means that the valves 151 , 161 and 171 each occupy their throughflow position and the valves 152 , 162 and 172 each occupy their blocking position.
[0038] In order to carry out service or normal braking operations, in the represented basic positions of the valves 151 , 152 , 161 , 162 , 171 and 172 there is a direct hydraulic connection between the master cylinder 112 and the wheel brakes 150 and 160 . Thus, an operation of the master cylinder 112 gives rise in the wheel brakes 150 and 160 to a brake pressure, the amount of which (initially without regard to a hydraulic brake boosting) depends upon the force F initiated by the driver and upon the gain factor of the brake booster 114 . A pressure sensor 141 picks up a pressure prevailing in the master cylinder 112 and may be used to detect the need for an additional hydraulic pressure boost.
[0039] The valves 151 , 152 , 161 and 162 and an accumulator 121 allow the implementation of an antilock control operation (ABS). The ABS functionality at this point is of no further significance, and the person skilled in the art knows how the valves 151 , 152 , 161 and 162 have to be actuated in order as a function of the driving state to increase, maintain and/or reduce a hydraulic brake pressure acting upon the wheel brakes 150 and 160 . In the following consideration of the mode of operation of the brake system 100 , it is assumed that an ABS function is not activated and that the valves 151 , 152 , 161 and 162 occupy the positions shown in FIG. 1 .
[0040] The brake system 100 further comprises a hydraulic pump 131 , for example in the form of a radial piston pump, which is actuable by an electric motor 132 . The hydraulic pump 131 is blocking counter to its delivery direction, as is represented by the blocking valve 133 at a high-pressure side of the pump 131 and by the blocking valve 134 at a low-pressure side of the pump 131 . The rotational speed of the electric motor 132 is controllable so that the delivery rate of the pump 131 may be adjusted. It is possible for the electric motor 132 simultaneously to actuate a pump of the second brake circuit II., which is not represented in detail here.
[0041] As already explained, the brake system 100 allows a hydraulic brake boosting for example in situations, in which the vacuum brake booster 114 has reached its maximum gain. In order to effect the hydraulic brake boosting, the valves 171 and 172 are actuated in such a way that the valve 171 occupies its blocking position and the valve 172 occupies its throughflow position. As a result, on the one hand the output of the pump 131 is hydraulically separated from the master cylinder 112 , i.e. a direct hydraulic connection exists only between the output of the pump 131 and the wheel brakes 150 and 160 . On the other hand there is a hydraulic connection from the low-pressure side of the pump 131 to the master cylinder 112 and/or the container 111 , thereby allowing the pump 131 to take in hydraulic fluid from the container 111 in order to additionally generate brake pressure in the wheel brakes 150 and 160 .
[0042] Optionally and not as an absolute necessity for a function according to the invention a pressure control valve 173 is connected in parallel to the valve 171 . The pressure control valve 173 ensures that the brake pressure generated at the high-pressure side of the pump 131 when the valve 171 is in blocking position does not exceed a predetermined value. In the embodiment represented in FIG. 1 the pressure control valve 173 is designed to limit the brake pressure generated by the pump 131 in the event of a malfunction in order to avoid damage to the brake system 100 , for example as a result of overloading.
[0043] In a further embodiment, the pressure control valve 173 may be designed to be electrically adjustable to a specific limit pressure. In this case the pressure difference, which is crucial for the pressure-limiting function and at which the pressure control valve 173 automatically transfers into its let-through position, is adjustable by means of the electrical control. As an electrical control, use is made for example of pulse width modulation, the pulse/pause ratio of which is adjustable in such a way that in dependence thereon the pressure difference that is crucial for the pressure-limiting function may be controlled and/or regulated as a function of the pulse width modulation.
[0044] In a further non-represented embodiment the valve 171 and the pressure control valve 173 may be combined in a valve arrangement. Such valve arrangements are known as ISO valves. Such a valve arrangement is known for example from DE 4 439 890 C2.
[0045] The brake system 100 is moreover capable of bringing about an electronic brake force distribution. For the electronic brake force distribution the pressure control valve 173 may be actuated independently of a drive circuit of the pump 131 in order in the first brake circuit I. to limit a maximum brake pressure acting upon the wheel brakes 150 and 160 , and hence a maximum brake force acting upon the wheels connected to the wheel brakes 150 and 160 , while in the second brake circuit II. (as yet) no such limitation is effected.
[0046] FIG. 2 shows a functional overview of a brake system 200 with hydraulic brake boosting 220 and electronic brake force distribution 230 , like for example the brake system 100 according to FIG. 1 . The corresponding functionalities 220 , 230 may be implemented in control units or control unit modules.
[0047] A detector 210 (for example a suitable sensor) picks up a state of the vehicle, which is decelerated by means of the brake system 200 . As already mentioned above, the detector 210 may acquire and process a large number of different measured values, for example a laden state, a velocity, an inclination of the vehicle in a longitudinal- or transverse direction, a yaw rate, a wheel slip at a rear axle, a wheel slip at a front axle, a vehicle velocity, a rotational speed of a wheel, and an angle of rotation of a steering wheel of the vehicle.
[0048] The detector 210 is connected to the electronic brake force distribution 220 and supplies it with signals that characterize the state of the vehicle. The electronic brake force distribution 220 determines whether or not the state determined by means of the detector 210 requires a distribution of the brake force, and as a function thereof supplies the hydraulic brake boosting 230 with a signal that indicates a (maximum) brake pressure to be adjusted at a rear axle of the vehicle. This brake pressure that is to be adjusted is determined by the electronic brake force distribution 220 by means of a pressure generation limitation 225 .
[0049] In a vehicle without EBD the hydraulic brake boosting 230 may be connected, instead of to the electronic brake force distribution 220 , to a pressure sensor that picks up a brake pressure in a master cylinder 112 . In the illustrated embodiment, the signal that is supplied by the electronic brake force distribution 220 to the hydraulic brake boosting 230 may therefore be a simulation of a pressure sensor signal. In particular, in a state of the vehicle, in which no brake force distribution is required, the signal supplied by the electronic brake force distribution 220 may correspond to an actual brake pressure (determined for example by means of the detector 210 ). However, in a state of the vehicle, in which a brake force distribution is required, the signal supplied by the electronic brake force distribution 220 may correspond to a brake pressure lower than the actual brake pressure, and in particular the signal may correspond to a limited brake pressure that ensures that the wheel brakes 150 , 160 of the rear axle are not actuated to an extent that jeopardizes a directional stability of the vehicle.
[0050] An exchange of data and/or commands between the electronic brake force distribution 220 and the hydraulic brake boosting 230 may for example take the form of a data interface. In particular, the electronic brake force distribution 220 and the hydraulic brake boosting 230 may be computer programs that are run on a common processing unit. The data interface may in this case be purely software-based.
[0051] The hydraulic brake boosting 230 then in accordance with the signal received from the electronic brake force distribution 220 controls a pressure build-up unit 240 , which supplies a brake pressure for one or more wheel brakes 150 , 160 of the rear axle of the vehicle. In this case, the brake pressure at the wheel brakes 150 , 160 follows the selections of the hydraulic brake boosting 230 , which in accordance with the vehicle state follows the selections of the electronic brake force distribution 220 .
[0052] FIG. 3 shows a schematic flowchart 300 of a method of building up a brake pressure. The representation of the method 300 is based on a brake system like the brake system 100 shown in FIG. 1 . In the following, therefore, reference is made once again to elements of FIG. 1 .
[0053] In a first step 310 a braking operation is initiated. This may be implemented for example by actuation of a brake pedal by a driver.
[0054] In a next step 320 it is determined whether an electronic brake force distribution is required. For this purpose, a driving- and/or vehicle state is acquired for example by sampling and processing measured values of the vehicle. The acquiring of the driving- and/or vehicle state may comprise acquiring a vehicle velocity, a wheel slip at front wheels and/or at rear wheels. The determining whether an EBD functionality is required may comprise comparing one or more parameters with associated threshold values.
[0055] If in step 320 it is determined that an electronic brake force distribution is not required, then in a step 330 it is determined whether a hydraulic brake boosting is required. If this second requirement does not exist, then in a step 340 a conventional braking operation occurs, during which neither an HBB- nor an EBD functionality is active. Otherwise, in a step 350 a brake pressure is built up in accordance with the conventional HBB selections.
[0056] If on the other hand in step 320 it is established that an electronic brake force distribution is required, then in a next step 360 it is determined whether a hydraulic brake boosting is already active or required. If this is not the case, in a step 370 the brake pressure acting upon the wheel brakes 150 , 160 of the rear axle of the vehicle is limited within the framework of the conventional EBD functionality without an HBB functionality being or having been activated. The limiting of the brake pressure is effected for example by corresponding actuation of the valves 171 and/or 172 , the pump 131 and/or the electric motor 132 selectively in the first brake circuit I.
[0057] If on the other hand in step 360 it is determined that a hydraulic brake boosting is also active or required, then in a next step 380 the brake pressure generated by the HBB functionality is limited to a value in accordance with the selection of the electronic brake force distribution. In this case, as is illustrated in FIG. 2 , the HBB functionality is actuated by the EBD functionality in such a way that a higher brake pressure than a required brake pressure is initially not generated at all by the pump 131 or, if a higher brake pressure has already been adjusted, the brake pressure is reduced to the required brake pressure.
[0058] The determinations, whether an electronic brake force distribution (step 320 ) and/or a hydraulic brake boosting (steps 330 , 360 ) is required, may alternatively be carried out in the reverse order or in parallel to one another. After the brake pressure has been adjusted in one of the steps 340 , 350 , 370 or 380 , the method returns to the step 310 , from which the described steps may also be executed afresh.
[0059] FIG. 4 shows a time characteristic 400 of various pressures of a brake system like the brake system 100 represented in FIG. 1 . In the following reference is made once again to elements of FIGS. 1 and 2 . The basis is a vehicle, the brake system of which has two mutually separate brake circuits, of which one (I.) acts upon two wheel brakes of a front axle and the other (II.) acts upon two wheel brakes 150 and 160 of a rear axle. The brake system of the vehicle further has a conventional, vacuum-controlled brake booster 114 . A possibly provided ABS- or ESP functionality is disregarded in the representation in FIG. 4 .
[0060] The curve 410 describes a hydraulic pressure in the master cylinder 112 of the brake system 100 of the vehicle. The curve 420 describes a brake pressure at the rear wheel brakes 150 and 160 , while the curve 430 describes a brake pressure at front wheel brakes of the vehicle. In horizontal direction the time is plotted, in vertical direction a hydraulic pressure in bars.
[0061] Between the times t 0 and t 1 there occurs an actuation of the brake pedal 113 with increasing actuating force by the driver of the vehicle as well as an associated, matching increase of the three pressures 410 , 420 and 430 .
[0062] At the time t 1 the brake booster 114 reaches its maximum gain, for example because a vacuum reservoir associated therewith is exhausted. At the same time a hydraulic brake boosting is activated, which actuates the valves 171 and 172 as well as the pump 131 and the electric motor 132 . Between the times t 1 and t 2 the rear wheel brake pressure 420 and the front wheel brake pressure 430 increase substantially identically and linearly. As indicated by the ripple in the characteristics of the brake pressures 410 and 420 , a drive pattern of the electric motor 132 and a delivery response of the pump 131 have the effect that both pressure characteristics are slightly pulsating. The pressure 410 in the master cylinder increases more slowly between t 1 and t 2 than before the time t 1 . The driver may notice this by feeling a varied resistance at the brake pedal 113 connected to the master cylinder 114 .
[0063] At the time t 2 the pressure 420 at the rear wheel brakes 150 and 160 has reached a value that allows a wheel slip at the rear wheel brakes 150 and 160 to become great enough for there to be only just no danger of the tail of the vehicle swerving to the right or left. In order to avoid reaching an unstable driving- and/or vehicle state as a result of a further increased pressure variation at the rear wheel brakes 150 and 160 , at the time t 2 an electronic brake force distribution is activated, which limits the brake pressure 420 at the rear wheel brakes 150 and 160 . For this purpose, as illustrated in FIGS. 1 and 2 , the electronic brake force distribution 220 prompts the hydraulic brake boosting 230 to control the pump 131 and/or the electric motor 132 in such a way that the rear wheel brake pressure 420 remains at the instantaneous value. The front wheel brake pressure 430 is not subject to the electronic brake force distribution 220 and therefore remains dependent only upon the pressure 410 in the master cylinder 112 and is not limited.
[0064] Since as a result of the activated electronic brake force distribution 220 it is already known at the time t 2 that the rear wheel brake pressure 420 is not to be increased further, as an alternative or in addition to the described pump control the valves 171 and 172 may both be transferred into a blocking state so that the rear wheel brake pressure 420 at the rear wheel brakes 150 and 160 is “blocked in”. If the electric motor 132 does not also drive a pump of the other brake circuit (II.), then the electric motor 132 may likewise be stopped. By virtue of these measures, unnecessary wear and annoyance caused by noise, vibration and harshness (NVH) may be reduced.
[0065] Between the times t 2 and t 3 there occurs a further increase of the pressure 410 in the master cylinder as a result of a corresponding actuation by the driver. In dependence upon the rise of the pressure 410 in the master cylinder the front wheel brake pressure 430 also rises, while the rear wheel brake pressure 420 remains constant because of the activated brake force distribution.
[0066] At the time t 3 the pressure 410 in the master cylinder has reached a maximum value, which means that the driver is actuating the brake pedal with a force F that now remains constant. Between the times t 3 and t 4 , in addition to the rear wheel brake pressure 420 the front wheel brake pressure 430 also remains substantially constant.
[0067] At the time t 4 two valves in the brake circuit I., which correspond to the valves 171 and 172 in the brake circuit II., are both transferred into a blocking state so that, in the brake circuit I. too, the brake pressure 430 at the front wheel brakes is “blocked in” and the brake pressure 430 in the further characteristic no longer demonstrates the roughness caused by the pump. At this time the pump and/or the actuation of the pump of the brake circuit I. may likewise be deactivated in order to further reduce NVH and prevent unnecessary wear.
[0068] Up to the time t 5 the pressures 410 , 420 and 430 remain constant. Then the driver begins to reduce an actuation of the brake pedal 113 , this being reflected in a linearly decreasing pressure 410 in the master cylinder 112 . In a corresponding manner, between the times t 5 and t 6 the front wheel brake pressure 430 is also reduced. The rear wheel brake pressure 420 however continues to be held constant at its limit value.
[0069] At the time t 6 the front wheel brake pressure 430 drops below the limit value selected for the rear wheel brake pressure 420 . Between the times t 6 and t 7 a further reduction of the pressure 410 in the master cylinder occurs. Thus, the rear wheel brake pressure 420 follows the front wheel brake pressure 430 and decreases linearly in proportion to the pressure 410 in the master cylinder. Between the times t 7 and t 8 the hydraulic brake boosting is deactivated and a residual functionality of the conventional brake booster 114 is utilized. The pressure 410 in the master cylinder in this section corresponds once more to the rear wheel brake pressure 420 and the front wheel brake pressure 430 . At the time t 8 the pressures 410 , 420 and 430 reach the value zero.
[0070] The person skilled in the art understands that the embodiment described with reference to FIGS. 1 to 4 may be modified, supplemented and adapted in many ways. Thus, the invention may be implemented for example also in an electrohydraulic brake system.
[0071] In accordance with the provisions of the patent statutes, the principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope. | The invention relates to a technology for effecting electronic brake force distribution in a vehicle brake system, which is equipped with a hydraulic brake boosting, comprising detecting a state requiring an electronic brake boosting and a limiting of the brake pressure generation of the hydraulic brake boosting according to the electronic brake boosting. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a Non-provisional Patent Application of U.S. Provisional Patent Application No. 61/036,588, entitled “Training Nozzle/Tip for Welding Applications”, filed Mar. 14, 2008, which is herein incorporated by reference.
BACKGROUND
The invention relates generally to welding guns, and more particularly to positioning attachments for controlling torch angle and/or torch to workpiece height during welding.
Welding is a process that has increasingly become ubiquitous in all industries. While such processes may be automated in certain contexts, a large number of applications continue to exist for manual welding operations, the success of which relies heavily on the proper use of a welding gun or torch. For instance, an improper torch angle can lead to a spatter, improper penetration, and overall poor weldments. However, inexperienced welders often have difficulty establishing the proper torch angle and torch to workpiece distance during welding, and such skills may be somewhat difficult to teach. Furthermore, even experienced welders may have difficulty maintaining these important parameters throughout welding processes.
Certain gas nozzles have been proposed that are used to establish the proper torch to workpiece distance during spot welding. However, these nozzles are less than satisfactory in addressing the overall problem, in particular because they do not establish the proper torch angle, are limited in scope to spot welding applications, and do not teach proper technique. Therefore, there exists a need for a device that will aid welders or welding trainees in establishing the proper torch angle and torch to workpiece distance.
BRIEF DESCRIPTION
The present invention provides a device designed to respond to such needs. The invention may be used in conjunction with a variety of welding guns as well as for multiple types of welding. It may be used solely for training purposes or during routine welding operations as well. In particular, the invention provides a positioning attachment for guidance of torch angle and/or torch to workpiece distance. The positioning attachment may contain one or more legs of equal or different lengths, that may be capped with a tip, and that contact the workpiece. The leg or legs extend from a body, which may be permanently attached or removably secured to the welding torch nozzle, or any other component of the welding torch. Certain embodiments may be made of heat resistant metals or ceramic to withstand high temperatures during welding.
DRAWINGS
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
FIG. 1 is a perspective view of a welding torch with a positioning attachment;
FIG. 2 is a side elevation view of a weld and a welding nozzle with a positioning attachment;
FIG. 3 is a top perspective view of a welding nozzle with a positioning attachment;
FIG. 4 is a further view of the add-on attachment and the welding nozzle;
FIG. 5 is a side elevation view of a three-legged positioning attachment;
FIG. 6 is a side elevation view of the positioning attachment in a welding position;
FIG. 7 is a front elevation view of a positioning attachment with two equal length legs;
FIG. 8 is a front elevation view of a positioning attachment with two slightly unequal length legs;
FIG. 9 is a front elevation view of a positioning attachment with two unequal length legs;
FIG. 10 is a front elevation view of a leg of the positioning attachment and a tip;
FIG. 11 is a side elevation view of a welding nozzle with a contact tip extension;
FIG. 12 is a side elevation view of a welding nozzle with an angled contact tip extension;
FIG. 13 is a perspective view of a further embodiment including 4 legs or prongs of unequal length; and
FIG. 14 is a perspective view of another embodiment having 4 legs.
DETAILED DESCRIPTION
FIG. 1 illustrates a welding torch 10 that incorporates a positioning attachment 12 , which establishes the proper torch angle and/or torch to workpiece height during welding or welding training. The torch 10 has a handle 14 with a trigger 16 , which a welder may use to start and stop welding. An extension 18 from the handle 14 is connected to a nozzle 20 . A contact tip 22 extends outward from the inner cavity of the nozzle 20 . One embodiment of the present invention, which includes two positioning legs 24 , 26 permanently attached to the outside of the nozzle on either side of the aperture 28 , is shown in FIG. 1 . During welding, wire is fed out of the contact tip 22 while gas is fed out of the aperture 28 into the welding area. In certain embodiments, the positioning attachment 12 may be made of a metal, such as brass or steel, which is resistant to the heat generated during welding. In other embodiments, the positioning attachment 12 may be made of ceramic. It should be noted that, although the embodiments illustrated in the figures relate generally to metal inert gas (MIG) welding arrangements, the invention may be adaptable to other systems and technologies, such as tungsten inert gas (TIG) torches.
FIG. 2 illustrates one embodiment of the present invention in which the positioning attachment 12 is permanently secured to the welding gun nozzle 20 . In this embodiment, one positioning leg 24 may be longer than the second positioning leg 26 so that the gun can be precisely positioned during the weld 30 . In the illustration of FIG. 2 , for example, the weld 30 is progressing in a right to left direction 32 . The positioning attachment 12 ensures that a proper torch to weld height 34 and torch angle 36 are maintained as welding proceeds in the indicated direction 32 . FIG. 3 illustrates a top perspective view of this weld process. The first positioning leg 24 is located in front of the weld as the nozzle 20 moves in the indicated direction 32 .
FIG. 4 illustrates one possible embodiment of the present invention. In this embodiment, an add-on attachment 38 is the means for removably securing the positioning attachment 12 to the nozzle 20 . The body 40 of the add-on attachment 38 is positioned around the nozzle 20 while the inner surface 42 of the add-on attachment 38 fits onto the tip of the nozzle 20 . In this embodiment, the positioning attachment 12 is removably secured to the nozzle 20 , enabling easy replacement and mobility between torches.
FIG. 5 illustrates a three leg positioning attachment 44 . In this embodiment of the present invention, two opposed positioning legs 46 , 48 are of equal length and are perpendicular to the body 40 of the positioning attachment 12 . The third rear leg 50 is a different length and connects to the body 40 at an angle. The three positioning legs 46 , 48 , 50 establish a fixed torch angle and torch to work piece height. In certain embodiments, the three leg positioning attachment 44 is made of a heat resistant metal while in other embodiments it may be made of ceramic. FIG. 6 illustrates a side elevation view of the three leg positioning attachment 44 connected to the welding nozzle 20 during welding. The opposed leg 46 and the rear leg 50 define the proper torch angle 52 as the welding torch is moved along the workpiece. It should also be noted that, where desired, the legs may all be of different lengths, and the one leg may follow along the center of the intended weld, or may be displaced to the side of the intended weld location. Additionally, in further embodiments, the positioning attachment 44 may have more than three legs, which establish the proper torch angle and/or torch to workpiece height during welding or welding training.
FIG. 7 is an illustration of a side elevation view of a level positioning attachment 54 in which the positioning legs are the same length. In this embodiment, the torch angle 56 is set to zero (i.e., generally perpendicular to the workpiece), and the torch to workpiece height is fixed 58 . In another embodiment, the positioning legs are of unequal lengths, and an angled attachment 60 is formed as shown in FIG. 8 . The unequal leg lengths create a torch angle 62 , which is greater than that of the level positioning attachment 54 , and a fixed torch to workpiece height 64 . In a similar embodiment, an angled attachment 66 has positioning legs that are of more unequal lengths, leading to an even greater torch angle 68 and a fixed torch to workpiece length 70 . In other embodiments, the lengths of the positioning legs may be any combination of intermediates between the shown illustrations.
FIG. 10 illustrates the positioning leg end 72 and a tip 74 , which securely fit together in the assembled positioning attachment 12 . In certain embodiments, the positioning tip 74 may be made of a heat resistant metal or ceramic such that it may interface with (e.g., contact) the workpiece in an area of intense heat from the weld. The removability of the tip 74 allows for easy replacement should it wear or degrade over time.
FIG. 11 is an illustration of one embodiment of the present invention in which the positioning attachment 12 takes the form of a special contact tip extension 76 . This extension 76 extends inside the nozzle 20 . This embodiment could either be used solely for training purposes, that is, for illustration of the correct torch angle and torch to workpiece length, or for welding as well as training if the extension 76 is made of a material sufficiently resistant to the temperatures present during welding. FIG. 12 shows another adaptation of this embodiment where the contact tip extension 78 is angled. The extension 78 still extends into the nozzle 20 and defines the proper torch angle and/or torch to workpiece distance.
FIG. 13 illustrates a further embodiment in which the torch attachment includes 4 legs. As in the previous embodiments, the attachment includes a body 80 that may be configured for snapping onto or otherwise fitting to an end (e.g., a nozzle) of a welding torch. This embodiment, however, includes a front leg 82 , two side legs 84 and 86 , and a rear leg 88 . The lengths of the legs are selected to properly orient a torch to which the device would be attached. In this embodiment, for example, the front leg 82 is longer than the rear leg 88 , causing the torch to be leaned downwardly during welding, with the front leg riding along a line where a weld is to be formed, and the rear leg riding over a progressing weld. The two side legs are shorter than both the front and the rear legs, and may contact workpieces on either side of a progressing weld. This embodiment may be particularly well suited to welds formed between workpieces joined at an angle.
FIG. 14 illustrates another embodiment of the attachment with 4 legs. In this embodiment, a body 90 has a front leg 92 extending from it, with two intermediate legs 94 and 96 somewhat shorter than the front leg, and a read leg 98 somewhat shorter still. The attachment will cause the torch to be leaned downwardly with the front leg again riding along a line where a weld is to be formed, and the rear leg riding over a progressing weld. The side legs will then ride along sides of the weld. This embodiment may be well suited for welds formed between abutted workpieces (e.g., plates).
In both embodiments with 4 legs, the lengths of the legs may be selected to provide the proper height of the torch about the weld location, and the proper angle of the torch with respect to the workpiece or workpieces. The side legs, for example, may be the same or different lengths to provide for a particular orientation of the torch. Similarly, other arrangements may be envisioned in which the legs are intended to straddle the weld rather than to ride along an intended weld line or a recently formed weld.
While only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. | A positioning attachment for definition of torch angle and torch to workpiece distance during welding and/or training is provided. The positioning attachment includes one or more legs of equal or varied lengths capped with a tip, which contacts the workpiece, and a body, which may be permanently attached or removably secured to the welding torch nozzle. Certain embodiments may be made of heat resistant metals or ceramic to withstand high temperatures during welding. The positioning attachment may be mounted on the welding torch nozzle or provided as an extension of the contact tip. | 1 |
This application is a division of Application Ser. No. 798,925, filed Nov. 18, 1985, now abandoned.
The subject invention relates to methods for food preparation and, more particularly, to a method of removing surface water from food items.
BACKGROUND OF THE INVENTION
Many food items, such as salad greens, are commonly prepared by washing them under a faucet and draining them using a perforated bowl such as a colander. Many vegetables, due to the size and curvature of their leaves, provide pockets which collect water. Such pockets, as well as the adhesion of water drops to the surfaces of leaves and stems, prevent or slow draining of water from the greens. Rapid shaking of the colander is not satisfactory as it tends to broadcast water in all directions. Additionally, some greens may fall from the colander and require rewashing. Placing the washed food items on absorbent paper or cloth is one solution, but is time-consuming and requires substantial counter space and absorbent material.
To overcome these difficulties, various washer/dewaterers for food items have been proposed. These devices typically include a rotatable perforated inner bowl for receiving the food items, an outer bowl rotatably holding the inner bowl, a top having an opening for receiving water, and a mechanism for spinning the inner bowl. It will be appreciated that such devices are relatively expensive, take up a large amount of storage space and require cleaning and drying after each use.
SUMMARY OF THE INVENTION
Among the several aspects and features of the present invention may be noted the provision of an improved dewaterer for food items. The dewatering device is extremely light in weight and requires a minimum of storage space. The device is formed entirely of thinwall sheet material, such as plastic, and dewatering is effected by revolving the device, usually manually, thereby causing centrifugal force to remove water from the food items. The dewaterer functions to collect the water removed from the food items and to substantially prevent the water from returning to the food items. The device is reliable in use, can be economically manufactured, and its cost is sufficiently low that it can be discarded after use. Other aspects and features of the present invention will be in part apparent and in part pointed out hereinafter in the following specification and accompanying drawings.
Briefly, the dewatering device of the present invention comprises a bag formed of thinwall sheet material divided into a first compartment and a second compartment. The first compartment is adapted to receive washed food items, and has a throat adjacent its bottom sized to permit passage of water therethrough but substantially to prevent passage of the food items therethrough. The second compartment is in fluid communication with the first compartment through the throat, and functions to collect water therein. By twirling or otherwise revolving the bag, surface water on food items in the first compartment is centrifugally forced off the surface of the food items and through the throat into the second compartment, where it is collected and retained to subsequently be discarded.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of the dewatering device of the present invention;
FIG. 2 is a side elevational view of a bag having a first compartment for receiving the food items, a second compartment for receiving water expelled from the first compartment and ribbons formed at the top of the bag for increasing the radius of rotation of the device;
FIG. 3 is a perspective view of the device of FIG. 1; and
FIG. 4 is a fragmentary view of an alternative embodiment of the dewaterer of the present invention including a funnel shaped throat between the first compartment and the second compartment.
Corresponding reference characters indicate corresponding components throughout the several views of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIGS. 1-3, a dewatering bag for use in the course of preparation of food items such as salad greens, is generally indicated by the reference numeral 20. The bag 20 is formed throughout from thinwalled sheet material, and includes a first compartment 22 for receiving the food items to be dewatered. The compartment 22 has an opening 24 at its top 26 for reception and removal of the food items. The first compartment 22 also includes a throat 28 adjacent its bottom 30 which is sized to pass water but is also sized substantially to prevent passage of the food items therethrough. A second compartment 32, extends beyond the bottom 30 of the first compartment. The second compartment 32 has a closed bottom 34 and encompasses the throat 28 so that liquid flowing from the first compartment 22 is collected in the second compartment.
More specifically, the dewatering bag 20 may be formed by a pair of thinwall plastic sheets 40 and 42, of material such as polyethylene or polyvinyl chloride, with the sheets welded (thermally or sonically) along their margins 39 and 41 to form a sleeve. Alternatively, an extruded tube of thinwall plastic may be used so that no marginal welding is required. The bottom 34 of the second compartment may also be formed by welding, and the coextensive bottom 30 of the first compartment and top 36 of the second compartment, as well as the throat 28, are formed by a discontinuous transverse weld 38. Preferably, this weld 38 is arcuate, having a discontinuity forming the throat 28 at the centerline of the bag.
Each of the aligned sheets 40 and 42, which are welded together along their margins to form the compartments, preferably has a "T" shaped cut 43 adjacent the top 26 of the form ribbons 44. It will be appreciated that these ribbons 44 not only form ears for holding the bag but also function as extensions to increase the radius of revolution of the bag thereby increasing centrifugal force on the water to cause it to flow from the food items located in the first compartment through the throat 28 and to be collected in the second compartment 32.
Operation of the dewatering bag 20 of the present invention is as follows: The washed food items such as salad greens are loaded into the first compartment 22 through the opening 24. The user then holds the bag by the ribbons 44 and revolves or twirls it. This causes the water from the food items to be forced through the throat into the second compartment where the water is collected. The food items then can be removed through the opening 24, and the dewatering bag 20, with the water held by the second compartment 32, can be discarded. Alternatively, the water held in the second compartment can be drained by cutting of the compartment, and the food items can then be enclosed in the first compartment by tying the ribbons together, and placed in a refrigerator for subsequent use.
Referring to FIG. 4, a portion of an alternative embodiment 20A of the dewatering bag of the present invention is shown. Components of the device 20A corresponding to those of the device 20 are indicated by the reference numeral assigned to the component of the device 20 with the addition of the suffix "A". In the dewatering bag 20A, the portion of the transverse weld 38A defining the throat 28A includes a pair of convergent legs 46 extending toward the bottom 34A of the second compartment 32A to form a funnel 48. This results in the formation of a pocket 50 on each side of the funnel 48. Inversion of the device 20A with water held in the second bag 32A causes water to enter the pockets 50 rather than to return to the first bag 22A via the throat 28A. Of course, the user can collapse the throat by pinching, completely isolating the compartments from each other.
It will also be appreciated that while the dewatering bag 20 is of unitary construction, a dewaterer incorporating the features of the present invention may also be formed by a pair of bags with one disposed inside of the other. The inner bag would be somewhat shorter and the tops of the two bags would be held together so that upon revolving the dewaterer, water from the first bag would exit through a throat at the bottom of the first bag and be collected in the outer, envelopment bag.
Besides home use, the dewaterer 20 of the present invention is also particularly well suited for use in commercial establishments, such as restaurant kitchens and gourmet restaurants. The dewatering device 20 can be employed to dewater large or small quantities or even individual servings of the food items on an ad hoc basis.
Other uses for the dewatering device of the present invention will also be found. For example, it if is desired to remove excess salad dressing from a salad, the salad greens can be placed in the first compartment, and the excess dressing removed as above described. In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | A method of dewatering food items, such as salad greens. The method comprises the steps of placing the food items in a compartment formed of flexible thinwall sheet material, said compartment having an open top and an opening opposite the open top sized to permit passage of liquid but substantially to prevent passage of food items therethrough. The compartment is twirled by its open top to cause water from the food items to be expelled through the opening by centrifugal force. | 1 |
BRIEF DESCRIPTION OF THE INVENTION
Compounds having the formula ##SPC2##
The 5-oxide and 5,5-dioxide thereof, and the pharmaceutically acceptable acid addition and quaternary ammonium salts thereof, have useful pharmacological activities, and can be used in mammals to treat inflammation and to lower blood pressure. In formula I, and throughout the specification, the symbols are as defined below.
A can be a straight or branched chain alkylene group having 2 to 5 carbon atoms;
R 1 can be hydrogen, alkyl, alkoxy, trifluoromethyl, or halogen;
R 2 can be hydrogen or alkyl; and
R 3 can be hydrogen, alkyl, phenyl, or phenylalkyl.
The terms alkyl and alkoxy, as used throughout the specification, refer to groups having 1 to 8 carbon atoms. Alkyl and alkoxy groups having 1 to 3 carbon atoms are preferred.
The term phenylalkyl, as used throughout the specification, refers to groups of the formula ##SPC3##
Wherein alkyl is as defined above. Benzyl and phenethyl are the preferred phenylalkyl groups.
The term halogen, as used throughout the specification, refers to fluorine, chlorine, bromine, and iodine; fluorine and chlorine are preferred.
DETAILED DESCRIPTION OF THE INVENTION
The compounds of formula I (and the 5-oxides and 5,5-dioxides thereof) are prepared using as starting materials a substituted tetrahydro-4H-thiopyran-4-one having the formula ##SPC4##
Or a 1-oxide or 1,1-dioxide thereof, and a hydrazine having the formula
III H.sub.2 NNH--A--NR.sub.2 R.sub.3.
The compounds of formulas II and III are readily obtainable; see, for example, Journal of the American Chemical Society, 79:156 (1957) and Journal of Medicinal Chemistry, 7:493 (1964).
A substituted tetrahydro-4H-thiopyran-4-one of formula II can be prepared by reacting tetrahydro-4H-thiopyran-4-one with an appropriate benzaldehyde having the formula ##SPC5##
The corresponding 1-oxide or 1,1-dioxide can be prepared by reacting a substituted tetrahydro-4H-thiopyran-4-one of formula II with an appropriate amount of an oxidizing agent; sodium periodate is preferred for preparing a 1-oxide and hydrogen peroxide is preferred for preparing a 1,1-dioxide.
A hydrazine of formula III can be prepared by reacting an excess of hydrazine (H 2 NNH 2 ) with a haloamine having the formula
V X--A--NR.sub.2 R.sub.3,
wherein X is chlorine or bromine.
Reaction of a substituted tetrahydro-4H-thiopyran-4-one of formula II (or a 1-oxide or 1,1-dioxide thereof) with a hydrazine of formula V yields a product of formula I, or the corresponding 5-oxide or 5,5-dioxide. The reaction can be run in an organic solvent, preferably a lower alkanol such as methanol. While reaction conditions are not critical, the reaction will preferably be run at, or near, the reflux temperature of the solvent.
Alternatively, the compounds of formula I can be obtained by first reacting a substituted tetrahydro-4H-thiopyran-4-one of formula II with a hydroxyalkyl hydrazine having the formula
VI H.sub.2 NNH--A--OH
to form an intermediate having the formula ##SPC6##
An alcohol of formula VII can be reacted with an alkylsulfonyl or arylsulfonyl halide, preferably p-toluenesulfonyl halide, to yield a compound of the formula ##SPC7##
wherein Y is alkyl or aryl. The intermediate of formula VIII can be treated with an amine having the formula
IX HNR.sub.2 R.sub.3
to yield the products of formula I. This method is particularly useful in preparing those compounds of formula I wherein R 2 and R 3 are both hydrogen.
The 5-oxide and 5,5-dioxide derivatives of a compound of formula I can, alternatively, be prepared by oxidizing the corresponding 3a,4,6,7-tetrahydro-3-phenyl-7-(phenylalkylene)thiopyrano[4,3-c]pyrazole-2(3H)-alkanamine of formula I. Oxidation of a compound of formula I using one equivalent of sodium periodate or hydrogen peroxide yields the corresponding sulfoxide derivative. Oxidation of a compound of formula I using potassium permanganate or excess hydrogen peroxide yields the corresponding sulfonyl derivative. Alternatively, the sulfoxide and sulfonyl derivatives can be prepared by treating compounds of formula I with m-chloroperbenzoic acid. Treating a compound of formula I with an equivalent of m-chloroperbenzoic acid for from 2 to 24 hours at room temperature yields the corresponding sulfoxide derivative. Treating a compound of formula I, or a sulfoxide derivative of a compound of formula I, with two equivalents of m-chloroperbenzoic acid for 2 to 24 hours at room temperature (or for a shorter time with slight heating) yields the corresponding sulfonyl derivative.
The compounds of formula I form acid addition salts with inorganic and organic acids. These acid addition salts frequently provide useful means for isolating the products from reaction mixtures by forming the salt in a medium in which it is insoluble. The free base may then be obtained by neutralization, e.g., with a base such as sodium hydroxide. Any other salt may then be formed from the free base and the appropriate inorganic or organic acid. Illustrative are the hydrohalides, especially the hydrochloride and hydrobromide which are preferred, sulfate, nitrate, phosphate, borate, acetate, tartrate, maleate, citrate, succinate, benzoate, ascorbate, salicylate, methanesulfonate, benzenesulfonate, toluenesulfonate and the like.
The compounds of formula I form quaternary ammonium salts with alkyl halides (e.g., methyl chloride, isobutyl bromide, dodecyl chloride and cetyl iodide), benzyl halides (e.g., benzyl chloride), and dialkyl sulfates (e.g., dimethyl sulfate).
The componds of formula I, the pharmaceutically acceptable acid addition salts thereof, the quaternary ammonium salts thereof, and the 5-oxide and 5,5-dioxide thereof, are useful in treating inflammation in mammalian species, e.g., rats, dogs, cats, monkeys, etc. Joint tenderness and stiffness (in conditions such as rheumatoid arthritis) are relieved by the above described compounds.
Additionally, the compounds of formula I, the pharmaceutically acceptable acid addition salts thereof, the quaternary ammonium salts thereof, and the 5-oxide and 5,5-dioxide thereof, are useful in lowering blood pressure in mammalian species.
The compounds of this invention can be formulated for use as anti-inflammatory agents and hypotensive agents according to accepted pharmaceutical practice in oral dosage forms such as tablets, capsules, elixirs, or powders, or in an injectable form in a sterile aqueous vehicle prepared according to conventional pharmaceutical practice. The compounds of this invention may be administered in amounts of 100 mg/70kg/day to 2 g/70kg/day, preferably 100 mg/70kg/day to 1 g/70kg/day.
The following examples are specific embodiments of this invention.
EXAMPLE 1
3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine
Tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one (5g) is refluxed with 2.1g of 3-dimethylaminopropylhydrazine in 50ml of methanol for 4 hours. The solvent is evaporated off and the residue is crystallized from 30ml of acetonitrile to yield 3.9g of the title compound, melting point 83°-85°C.
EXAMPLE 2
3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine, maleate
3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine (3.7g, prepared as described in Example 1) and 1.1g of maleic acid are dissolved in 30ml of warm acetonitrile and diluted with 100ml of ether. After cooling for about 16 hours, the material is filtered, washed with ether, and dried in vacuo. The material is crystallized from methanol-ether (3:20) yielding 4.2g of the title salt, melting point 147°-149°C.
EXAMPLE 3
3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5-oxide
A. Tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one, 1-oxide
A solution of 10.4g of sodium periodate in 50ml of water is added to a suspension of 7.0g of tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one in 300ml of methanol. The mixture is stirred at room temperature for 3 days (a water bath is used for the first hour to moderate a slightly exothermic reaction). Solvent is removed in vacuo and the residue is stirred with chloroform and filtered. The filtrate is concentrated in vacuo and the residue is crystallized from 150ml of methanol, giving 6.4g of the title compound, melting point 155°-160°C. A second crop of 0.5g of the title compound, melting point 154°-157°C is also obtained.
B. 3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2-(3H)-propanamine, 5-oxide (two isomers)
A stirred mixture of 2.5g of tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one, 1-oxide and 0.95g of 3-dimethylaminopropylhydrazine in 75ml of methanol is heated and the resulting solution is refluxed for 5 hours. After standing overnight at room temperature, the methanol is removed on a rotary evaporator and the residue is triturated with 100ml of boiling isopropyl ether to yield a solid, which after cooling weighs 2.0g, melting point 138°-140°C.
Thin layer chromatography (ethyl acetate on alumina) shows a mixture of compounds is present. Crystallization from 10ml of acetonitrile yields 0.9g of material, melting point 153°-155°C. (TLC: single spot; ethyl acetate on alumina R f 0.38). The acetonitrile liquor is evaporated and the residue is dissolved in 4ml of acetonitrile. Cooling overnight yields 0.15g of material, melting point 125°-127°C (TLC: essentially single spot; ethyl acetate on alumina, R f 0.31; small amount of material with R f 0.38 present).
EXAMPLE 4
3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5,5-dioxide
Tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one, 1,1-dioxide (4.9g, prepared as described in Journal of American Chemical Society, 79:156 (1957)) is reacted with 1.8g of 3-dimethylaminopropylhydrazine in 200 ml of methanol for 4 hours. The solvent is evaporated off and the residue is extracted with 400ml of boiling isopropyl ether, leaving 2.3g of material undissolved. The extract is filtered through glass wool and concentrated to 150ml; the title compound separates. After cooling for 72 hours, the material is filtered, washed with isopropyl ether and dried in vacuo to yield 3.5g of the title compound, melting point 127°-129°C.
EXAMPLE 5
3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5,5-dioxide, hydrochloride (1:1)
3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5,5-dioxide (3.4g) is dissolved in 25ml of warm methyl ethyl ketone, cooled and treated with 1.35ml of 6.1N alcoholic hydrogen chloride. On seeding and rubbing, the crystalline hydrogen chloride salt separates. Ether is added to complete the precipitation and after cooling for about 16 hours the solid is filtered, washed with ether and dried in vacuo to give 3.5g of material, melting point 183°-185°C. Following crystallization from 20ml of methanol-40ml of ether, there remains 2.6g of the title compound, melting point 192°-194°C.
EXAMPLE 6
3a,4,6,7-Tetrahydro-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-ethanamine
A. 3a,4,6,7-Tetrahydro-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-ethanol
Following the procedure of Example 1, but substituting (2-hydroxyethyl)hydrazine for 3-dimethylaminopropylhydrazine, yields the title compound.
B. 3a,4,6,7-Tetrahydro-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-ethanamine
3a,4,6,7-Tetrahydro-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-ethanol is suspended in pyridine and treated with one equivalent of tosyl chloride. After standing at room temperature for about 16 hours, the mixture is poured into water and the tosylate is dissolved in ethanol, cooled and saturated with ammonia gas. After standing for 3 days, the excess ammonia and solvent are removed by evaporation to give the title compound.
EXAMPLE 7
3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine, methochloride
A solution of 3.0g of 3a,4,6,7-tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine (from Example 1) in 30ml in acetonitrile is cooled and treated with 5.0g of methyl chloride gas. The resulting solution is allowed to stand at room temperature for a day and the solvent is evaporated to give the title compound.
EXAMPLES 8-14
Following the procedure of Example 1, but substituting the compound listed in column I for tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one and the compound listed in column II for 3-dimethylaminopropylhydrazine, yields the compound listed in column III.
__________________________________________________________________________ExampleColumn I Column II Column III__________________________________________________________________________ 8 tetrahydro-3,5-bis-[(2-methyl- methylaminopropylhydrazine 3a,4,6,7-tetrahydro-N-methyl-3-(2 -phenyl)methylene]-4H-thiopyran- methylphenyl)-7-[(2-methylphenyl) -4-one methylene]thiopyrano[4,3-c]pyrazo le- 2(3H)-propanamine 9 tetrahydro-3,5-bis-[(4-methoxy- N-benzyl-N-methylaminoethyl- 3a,4,6,7-tetrahydro-N-benzyl-N-phenyl)methylene]4H-thiopyran- hydrazine methyl-3-(4-methoxyphenyl)-7-4-one [(4-methoxyphenyl)methylene]thio- pyrano[4,3-c]pyrazole-2-(3H)-etha na- mine10 tetrahydro-3,5-bis-[(4-trifluoro- N-methyl-N-phenylaminopentyl- 3a,4,6,7-tetrahydro-N-methyl-N-methylphenyl)methylene]-4H-thio- hydrazine phenyl-3-(4-trifluoromethylphenyl )-pyran-4-one 7-[(4-trifluoromethylphenyl)methy l- ene]thiopyrano[4,3-c]pyrazole-2(3 H)- pentanamine11 tetrahydro-3,5-bis-[(2-chloro- (2-aminoethyl)hydrazine 3a,4,6,7-tetrahydro-3-(2-chloro-phenyl)methylene]-4H-thiopyran- phenyl)-7-[2-(chlorophenyl)methyl ene]-4-one thiopyrano[4,3-c]pyrazole-2(3H)- ethanamine12 tetrahydro-3,5-bis-(phenylmethyl- phenylaminopropylhydrazine 3a,4,6,7-tetrahydro-N-phenyl-3-ph enyl-ene)-4H-thiopyran-4-one 7-(phenylmethylene)thiopyrano[4,3 -c]- pyrazole-2(3H)-propanamine13 tetrahydro-3,5-bis-(phenylmethyl- benzylaminopropylhydrazine 3a,4,6,7-tetrahydro-N-benzyl-3-ph enyl-ene)-4H-thiopyran-4-one 7-(phenylmethylene)thiopyrano[4,3 -c]- pyrazole-2(3H)-propanamine14 tetrahydro-3,5-bis-[(4-propoxy- 3-(dimethylamino)-2-methyl- 3a,4,6,7-tetrahydro-N,N,β-tr imethyl-3-phenyl)methylene]-4H-thiopyran- propylhydrazine (4-propoxyphenyl)-7-[(4-propoxyph enyl)-4-one methylene]thiopyrano[4,3-c]pyrazo le- 2(3H)-propanamine.__________________________________________________________________________ | Anti-inflammatory activity and hypotensive activity are exhibited by compounds having the formula ##SPC1##
The salts thereof, and the 5-oxide and 5,5-dioxide thereof, wherein A is a straight or branched chain alkylene group; R 1 is hydrogen, alkyl, alkoxy, trifluoromethyl, or halogen; R 2 is hydrogen or alkyl; and R 3 is hydrogen, alkyl, phenyl, or phenylalkyl. | 2 |
TECHNICAL FIELD
[0001] The invention relates to a drag head for dredging purposes and to a trailing suction hopper dredger comprising such a head. The invention further relates to methods of dredging.
BACKGROUND
[0002] Dredging at sea or in open water may be carried out by dredging vessels, such as a trailing suction hopper dredger (TSHD). The dredging vessels comprise a suction tube one end of which can be lowered to the seabed and used to suck up solids such as sand, sludge or sediment, mixed with water. This lower end of the suction tube can be provided with a suction head. The solid material mixed with water is pumped through the suction tube into a hopper of the dredging vessel.
[0003] Once the hopper is full, the pumping may continue causing an overflow. The overflow will mainly be formed by water, as the solids tend to sink to the bottom of the hopper. The pumping may be stopped when it is no longer efficient to continue, as may be the case when the overflow is becoming too dense.
[0004] The higher the density of the mixture of solids and water that is pumped through the suction tube, the more efficient the dredging is performed. Dredging with relatively high densities has many advantages. In the first place, dredging can be performed in a more time and cost efficient way. Secondly, more solid material can be pumped into the hopper. Also, overflow losses will be reduced or will even disappear which is advantageous from an energetic point of view. Furthermore, reducing overflow losses will reduce turbidity.
[0005] One element of the dredging installation that may limit the maximum density is the trailing suction head provided at the lower end of the suction tube.
[0006] DE214643C discloses a suction tube and a trailing suction head. The suction tube has a bend near the trailing suction head such that the suction opening faces the direction of motion. In the suction opening an adjustable sled member is provided to control the dredging depth. Also, an adjustable plate member may be provided in the suction opening to control the amount of water entering the suction opening. A dragging force is applied directly to the suction head by the suction tube.
[0007] Other trailing suction heads are known which comprise a body which is arranged to be dragged along the seabed. The body comprises connection means for connecting to a suction tube which may also serve to impart the drag force on the body. A visor having a cutting edge is hingeably connected at a rear side of the body. The angle of orientation and/or the depth of the cutting edge of the visor can be adjusted with respect to the body by means of hydraulic piston/cylinder devices. Jet nozzles are provided in the body to facilitate the dredging process by breaking up the material of the sea bed and fluidizing it for removal via the suction tube. In order to lift the dredged material from the cutting edge towards the inlet to the suction tube, a significant amount of mixing with water is required leading to a reduction in density of the mixture. At present for sand and silt dredging, mixture densities of on average 1350 kg/m 3 are achievable. A drag head of this type is known from EP1653009A1. Similar drag heads are known from EP1108819A1 and AU2005200784A1, the contents of each of which are herein incorporated by reference in their entirety.
[0008] It would be desirable to provide an alternative to the above discussed drag heads, in particular one which is capable of sucking up mixtures of water and material with a relatively high density in a relatively efficient way whereby excess water transport is minimised.
SUMMARY
[0009] According to the invention, there is provided a drag head for dredging material from a bed of a body of water and transporting the material to a suction tube, the drag head being arranged to be dragged over the bed in a dragging direction by a drag member, wherein the drag head comprises a heel section being connectable to the drag member and having a bed engaging surface arranged to follow the bed and a suction section comprising a suction opening; a suction chamber; and an outlet for connection to the suction tube such that an underpressure can be created in the suction chamber to suck up the material from the bed through the suction opening into the suction chamber, wherein the suction section is adjustably mounted to the heel section such that an orientation of the suction opening can be adjusted relative to the heel section. By providing the suction section separately adjustable from the heel section, the orientation of the suction opening can be set independently of the position of the heel which is being towed along the bottom of the seabed. Such an arrangement is believed to be considerably more versatile in optimizing the direction and/or height of the suction opening. Since the outlet also forms part of the suction section, its orientation may also be adjusted together with the suction opening. In the present context, reference to material is intended to refer to solid or semi solid material including silt, sand, sediment, mud, gravel and fractured rock as may generally be encountered during suction dredging operations. Furthermore, although reference may be made to sea bed, this is equally intended to cover and include beds of rivers, lakes, canals, estuaries and the like.
[0010] According to the invention the heel section is arranged to be connected to a drag member. The drag member may be a dragging pole, bar, pipe, cable, chain or the like or the suction tube itself, which is connected with the vessel to drag the drag head over the seabed. In the present context, reference to the fact that the heel section is connected to the drag member is understood to mean direct or indirect connection therewith. The dragging force is subsequently applied to the suction section via the heel section. Preferably, the suction section is not connected to the drag member except via the heel section.
[0011] The suction section may be adjustable in various ways using appropriate mechanical means as will be known to the skilled person. According to a preferred embodiment of the invention, the suction section is rotatable with respect to the heel section about an axis of rotation which is in use substantially horizontal and perpendicular to the dragging direction. Most preferably, this axis lies generally behind the heel section and ahead of the suction section with respect to the direction of movement of the drag head. Preferably too, the axis is positioned relatively low with respect to the bed engaging surface in order to maximize the mass of the suction section that acts downwards.
[0012] According to a further aspect of the invention, the suction section may comprise a lower edge, e.g. a cutting edge, forming a trailing edge of the suction opening, wherein the lower edge or cutting edge is in use lower than the bed engaging surface of the heel section in order to dig into the material forming the bed. The lower edge or cutting edge is preferably substantially horizontal and substantially perpendicular with respect to the dragging direction and points at least partially in the dragging direction. By providing the lower edge or cutting edge below the bed engaging surface of the heel section, the suction opening will be directed in the dragging direction. By rotating the suction section with respect to the heel section the relative depth of the lower edge or cutting edge with respect to the bed engaging surface of the heel section can be adjusted and thereby the depth of channel dredged by the drag head.
[0013] The cutting edge may comprise a row of cutting members, which may be formed as (replaceable) teeth being placed in corresponding teeth holders. In general, the width of the cutting edge transverse to the dragging direction may be any appropriate width according to the operation being performed. Nevertheless, in general, the width of the cutting edge will not be more than the width of the bed engaging surface of the heel section. In a most preferred embodiment, both of these sections may have similar widths. It will also be understood that although in general the heel section will lie ahead of the suction section in the direction of movement, this position is not necessarily essential. The heel section may in certain configurations be located to one or both sides or around the suction section.
[0014] According to one embodiment of the invention, the width of the suction section decreases from the suction opening towards the outlet, most preferably in a gradual way. This smooth transition assists the transport of the dredged material towards the outlet and helps avoid significant energy losses. Preferably, the suction chamber may have a tapered or trumpet like shape to provide a smooth transition between the relatively large suction opening and the smaller outlet towards the suction tube. The term width is used here to indicate the dimension substantially perpendicular to the dragging direction and, in use, substantially horizontal. As an additional or alternative measure, the suction section may have a bottom plate which is at least partially inclined in an upward direction from the lower edge or cutting edge towards the outlet. The bottom plate ensures a smooth flow path for the material that is sucked up, thereby reducing the resistance. The bottom plate may be straight or curved.
[0015] According to an embodiment the suction section may be connected to the suction tube via a flexible connection. Providing a flexible connection has the advantage that the suction section can be moved with respect to the heel section and the suction tube. The suction tube may be provided on and move with the heel section or may be independent therefrom. The flexible connection may be provided by a flexible reinforced tube or concertina section. Alternatively it may be achieved by telescoping sections of rigid pipe. Preferably, the flexible section is of low-loss design in order to further reduce flow resistance to the dredged mixture, whereby transport of higher mixture densities may be achieved. In a further alternative, the suction tube itself may be flexible.
[0016] In one embodiment, the suction opening is at least partially bounded by the heel section. In such a configuration, the suction section and heel section may engage together to form the suction chamber. The engagement between the two sections should be sufficiently tight that suction losses and water inflow from between the two sections may be minimal. In a particularly preferred embodiment, the heel section and the suction section comprise two half shells that engage or telescope together to form the suction chamber. The heel section provides the bed engaging surface while the suction section carries the lower edge or cutting edge and forms the suction outlet.
[0017] The drag head may be provided with means to form a desired mixture density of the dredged material, optimized to achieve transport to the surface with minimal liquid content. The skilled person will be aware of various manners in which this may be achieved using swirl vanes, cutting blades and the like. According to a preferred embodiment the drag head may comprise a plurality of conduits having outlet openings or nozzles for delivering water jets into the suction chamber at or near the outlet. These nozzles may preferably be located on the suction section and most preferably around the outlet. Such water jets may be provided to fluidize the material to make transport of the material easier.
[0018] According to a further embodiment, the drag head may be provided with means for breaking up or loosening the material of the sea bed at or ahead of the lower edge or cutting edge. In this case too, the choice of measure provided will depend on the particular material being dredged and the skilled person will be aware of the alternatives that may be used. In a preferred embodiment, a plurality of conduits having outlet openings for forming water jets beneath the bed engaging surface of the heel may be provided. Not only do such jets make it easier to remove the material from the bottom but they may also assist in fluidizing it to the desired degree for further transport.
[0019] According to an embodiment the outlet from the suction chamber is at least partially directed in a direction opposite to the dragging direction. By orientating the outlet from the suction section in this way, the material is initially sucked in a direction at least partially opposite to the dragging direction. This may assist in providing a natural and undisturbed flow path for the material, allowing for an energy efficient suction operation.
[0020] According to a still further aspect of the invention, the drag head may be provided with an actuator arrangement for displacing the suction section with respect to the heel section. This actuator may be a hydraulic, pneumatic or mechanical actuator and can be automatically operated to set a desired orientation or depth of the suction section or the cutting edge.
[0021] In an alternative arrangement, the desired orientation may be achieved without actuator by using the natural mass of the suction section. This may be weighted or biased with respect to the heel section to achieve the desired orientation. In one embodiment, the position of the hinge may be adjustable to achieve the desired weighting. In this manner the depth of the lower edge or cutting edge may be adjusted depending e.g. on the dragging speed, seabed consistency and other related factors.
[0022] According to a further aspect of the invention, the heel section may be provided with a pump to provide suction to the suction chamber via the suction tube. Preferably the pump is a high performance submerged dredge pump for operating with high mixture densities such as a centrifugal pump. The pump may be carried directly on the heel section and may carry the suction tube. Alternatively, the pump and/or the suction tube may be provided at a remote position or may be mounted to the drag member. Preferably the pump is located at a suitable distance above the seabed to avoid damage and for most purposes will be located at about half the water depth in order to most efficiently assist in transport of the mixture.
[0023] The invention also relates to a vessel, such as a trailing suction hopper dredger, comprising a drag head as generally described above. In its working configuration, the heel section is attached to a drag member trailing from the vessel whereby the drag head may be dragged or towed along the seabed.
[0024] The invention further relates to a method of suction dredging a mixture of solids and water from the bed of a body of water using a drag head comprising a heel section and a suction section, the method comprising dragging the heel section across the bed in a first direction, positioning the suction section at a desired depth and angle with respect to the heel section such that the suction section at least partially engages and enters the bed, applying suction to the suction section to cause the bed material to be sucked up in a direction at least partially opposed to the first direction and be mixed with water and transporting the mixture to the surface.
[0025] Most preferably, the method is carried out for a mixture comprising sand and water having a density of more than 1650 kg/m 3 . As a result of the desirable drag head configuration, such densities may be efficiently dredged.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Embodiments will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:
[0027] FIG. 1 schematically shows a side view of a first embodiment of the invention;
[0028] FIG. 2 schematically shows a side view of a second embodiment of the invention;
[0029] FIG. 3 schematically shows a top view of the embodiment of FIG. 2 ; and
[0030] FIG. 4 schematically shows a cross-sectional view taken at line 4 - 4 in FIG. 3 .
[0031] The figures are meant for illustrative purposes only, and shall not serve as restriction of the scope or the protection as laid down by the claims.
DETAILED DESCRIPTION
[0032] With reference to the figures, embodiments will now be described in more detail. According to FIG. 1 , there is shown a schematic side view of a drag head 1 according to a first embodiment of the invention being used to dredge sand 2 or other similar material from the seabed 3 and transport it to a vessel 4 .
[0033] Drag head 1 comprises a heel section 11 in the form of a sled and a suction section 10 having the form of a bucket, articulated together at a generally horizontal hinge 8 . The heel section 11 is attached to a cable 16 via a pair of mounts 18 of which only one is shown. The cable 16 extends to the vessel 4 where it is held fast by a suitable derrick or boom 19 as is conventional in the art.
[0034] The heel section 11 has a bed engaging surface 22 on its underside. The bed engaging surface 22 is sufficiently long to ensure that the heel section assumes a substantially stable towing position. On its upper surface, heel section 11 carries a suction pump 50 which has a pump outlet 52 connected to a transport tube 54 leading to the surface and into a hopper 5 onboard the vessel 4 .
[0035] The suction section 10 has a suction chamber 12 within its interior with a suction opening 13 at its lower side. A trailing edge or lower edge of the suction opening 13 forms a cutting edge 15 . The cutting edge 15 may be provided with serrations (not shown). From the cutting edge 15 a bottom plate 17 leads up to an outlet 14 provided at an upper, rear side of the suction section 10 . The outlet 14 connects the interior of the suction chamber 12 to a flexible suction tube 20 . The suction tube 20 is connected to a pump inlet 51 on pump 50 .
[0036] In use, the drag head 1 is dragged along the seabed 3 by the cable 16 in a direction of motion D. The heel section 11 follows the seabed 3 and the blades 24 on the bed engaging surface 22 cut into the sand 2 and loosen it. The suction section 10 pivots about the hinge 8 due to its mass and causes the cutting edge 15 to dig into the sea bed 3 . The loosened sand 2 is scooped up by the cutting edge and rides up the bottom plate 17 towards the outlet 14 . The pump 50 is operated to generate suction in the suction tube 20 causing water to also be sucked up through the suction opening 113 . As the water and cut sand 2 approach the outlet 14 , the narrowing of the suction chamber 13 causes their velocity to increase whereby the sand 2 becomes entrained with the water. The resulting mixture is pumped via the pump 50 and transport tube 54 to the surface and into the hopper 5 . Due to the advantageous orientation of the suction opening 13 and the upward slope of the bottom plate 17 towards the outlet 14 , the cut sand can be carried away with relatively little entrainment of water and a relatively high density of the mixture.
[0037] A second embodiment of a drag head 100 according to the invention is shown in FIG. 2 in which like elements are provided with similar reference numerals preceded by 100 . FIG. 2 shows a heel section 111 and a suction section 110 which are hinged together at a hinge 108 forming a suction chamber 112 therebetween. The suction section 110 is slightly narrower than the heel section 111 , whereby both sections can partially telescope into each other by rotation about the hinge 108 . A lowermost or trailing edge of the suction section 110 is provided with a cutting edge 115 . The heel section 111 has a lowermost bed engaging surface 122 . Between the cutting edge 115 and the rear edge of the bed engaging surface 122 there is formed a suction opening 113 providing access to the suction chamber 112 .
[0038] In the embodiment of FIG. 2 , the heel section 111 further comprises a tubular body 140 rigidly attached to a front surface thereof. The tubular body 140 is in turn connected to a drag member 141 which is towed from the vessel 4 as in FIG. 1 . The drag member 141 and the tubular body 140 form a relatively rigid arm extending to the surface (although it will be understood that powered joints may be foreseen) which ensures that the angle of the heel section 111 with respect to the seabed remains substantially constant (for a given depth of water).
[0039] On an upper surface of the tubular body 140 there are provided a pair of actuators 130 (of which one is shown in this view) having piston arms 132 attached to an upper portion of the suction section 110 at a mount 134 . By operating the actuators 130 , the suction section 110 can be pivoted with respect to the heel section 111 to cause the cutting edge 115 to dig deeper into the sea bed.
[0040] As in the first embodiment, the suction section has a bottom plate 117 which leads upwards to an outlet 114 at an upper rear part of the suction section. Unlike the first embodiment, the outlet 114 is connected to a flexible connection 121 which in turn connects to the suction tube 120 . In this case, the pump 150 is carried by the drag member 141 and has a pump inlet 151 connected to the suction tube 120 and a pump outlet 152 connected to transport tube 154 .
[0041] FIG. 3 shows a plan view of the embodiment of FIG. 2 showing heel section 111 and suction section 110 engaging each other with actuators 130 determining the degree of rotation of the sections about hinge 108 . According to FIG. 3 , it can be seen that the heel section 111 and the suction section 110 have a maximum width W1 at the position of the cutting edge. From this position, the width of the suction section 110 decreases to a width W2 at the outlet 114 .
[0042] FIG. 4 is a sectional view taken on line 4 - 4 in FIG. 3 showing an interior of the suction chamber 112 . In this view, nozzles 160 can be seen located around outlet 114 . The nozzles 160 are connected to a suitable source of pressure (not shown) and are operated to generate pressurized jets of water within the outlet 114 directed towards the flexible connection 121 . Also visible in FIG. 4 are further nozzles 162 provided in the bed engaging surface 122 of the heel section 111 . The further nozzles 162 are in communication with a pressure manifold 164 within the heel section 111 into which pressurized water may be supplied from the source of pressure mentioned above.
[0043] In use, the drag head 100 is dragged along by the dredging vessel in the direction D with the heel section 111 engaging the seabed 3 . Pressurised water is provided to the manifold 164 which causes the formation of jets of water from further nozzles 162 beneath the bed engaging surface 122 . The jets of water loosen and partially break up the sand or silt 2 . The loosened sand 2 is cut and lifted by cutting edge 115 and enters suction chamber 112 through suction opening 113 . The reducing width of the suction chamber 112 and the bottom plate 117 funnel the sand 2 upwards towards the outlet 114 . At this stage, the sand contains a quantity of entrained water due to the further nozzles 162 . Nevertheless, the density is too high for it to be easily transported. As the sand and water mixture enters the outlet 114 additional water jets are injected through nozzles 160 . These jets further loosen the sand 2 and fluidise it to a desired final density of around 1650 kg/m 3 for transport via the pump 150 and transport tube 154 to the surface. Due to the increased density, the vessel 4 can be filled without overflow or further discharge back into the water which is highly advantageous for sensitive environments where such discharge during dredging is prohibited.
[0044] Thus, the invention has been described by reference to certain embodiments discussed above. It will be recognized that these embodiments are susceptible to various modifications and alternative forms well known to those of skill in the art. In particular, the arrangement of flexible connection of FIG. 2 may be replaced by a telescoping arrangement. Furthermore, the actual design may be distinct from the schematically illustrated designs.
[0045] Many modifications in addition to those described above may be made to the structures and techniques described herein without departing from the spirit and scope of the invention. Accordingly, although specific embodiments have been described, these are examples only and are not limiting upon the scope of the invention. | A drag head ( 100 ) for dredging material ( 2 ) from the bed ( 3 ) of a body of water and transporting the material ( 2 ) to a suction tube ( 120 ). The drag head ( 100 ) is arranged to be dragged over the bed ( 3 ) in a dragging direction (D). The drag head ( 100 ) includes a suction section ( 110 ) in which an under pressure can be created to suck up the material ( 2 ) from the bed ( 3 ) through a suction opening ( 113 ) into a suction chamber ( 112 ). A heel section ( 111 ) guides the drag head ( 100 ) along the bed ( 3 ). The suction section ( 110 ) is preferably rotatably connected to the heel section ( 111 ). The suction section ( 110 ) also includes an outlet ( 114 ) for transporting the material ( 2 ) towards the suction tube ( 120 ). | 4 |
FIELD OF THE INVENTION
The present invention relates to a damping element for a fuel injection valve.
BACKGROUND INFORMATION
A damping element for a fuel injection valve insertable into a receiving conduit of a cylinder head of an internal combustion engine, which element is disposed between a valve housing of the fuel injection valve and a wall of the receiving conduit of the cylinder head, is described in German Published Patent Application No. 100 38 763. The damping element is made up of two rigid rings between which an elastic intermediate ring is disposed. The damping element, inter alia, decreases acoustic transfer from the fuel injection valve to the cylinder head. It is disadvantageous that the damping element requires a great deal of axial installation space with respect to a valve axis, and has comparatively high manufacturing costs.
SUMMARY
The damping element according to example embodiments of the present invention, in contrast, may provide that an improvement may be achieved in simple fashion in that with a damping effect that is as good as in the existing art, less axial installation space with respect to the valve axis is necessary, in that the damping element is arranged in plate-shaped fashion. Sufficient elasticity of the damping element is achieved because of the plate-shaped arrangement and the mounting of the fuel injection valve on a collar of the plate-shaped damping element.
The damping element may have a first portion for bracing against a shoulder of the receiving conduit in the cylinder head and a second portion, angled with respect to the first portion, for bracing of the fuel injection valve, since axial installation space is saved by the angling of the second portion and sufficient elasticity of the damping element is moreover achieved.
The first portion may extend from the second portion radially inward with respect to a valve axis, since in this fashion the shoulder of the receiving conduit against which the damping element abuts is easier to manufacture than in the case of a first portion that extends radially outward from the first portion.
The first portion may be arranged in substantially flat or convex fashion.
The second portion may be arranged in collar-shaped, substantially conical, and/or convex fashion. The necessary elasticity of the damping element is thereby achieved.
The damping element may have a passthrough opening that can be penetrated by the fuel injection valve. The passthrough opening may be arranged on the first portion.
The first portion and the second portion may have at least one support, for bracing against the cylinder head or for bracing of the fuel injection valve, that is arranged in planar fashion or as an elevation. The smaller the support surface of the damping element on the cylinder head, the better the solid-borne sound-damping effect.
Provision may be made for the damping element to have two cover panels and an elastic intermediate layer disposed between the cover panels. This damping element fabricated from composite material exhibits particularly good solid-borne sound damping, since mechanical vibration energy is converted into thermal energy by internal friction in the elastic intermediate layer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional of a fuel injection valve in a receiving bore of a cylinder head
FIG. 2 illustrates aspects of an example embodiment of the present invention.
FIG. 3 illustrates aspects of an example embodiment of the present invention.
FIG. 4 illustrates aspects of an example embodiment of the present invention.
DETAILED DESCRIPTION
Several exemplary embodiments of the present invention are depicted in simplified fashion in the drawings and explained further in the description that follows. FIG. 1 shows, in section, a fuel injection valve in a receiving bore of a cylinder head, FIG. 2 illustrates aspects of an exemplary embodiment, FIG. 3 illustrates aspects of an exemplary embodiment, and FIG. 4 illustrates aspects of an exemplary embodiment, in respective details II-IV according to FIG. 1 .
FIG. 1 is a simplified depiction of a fuel injection valve in a receiving bore of a cylinder head, having a damping element according to example embodiments of the present invention between the fuel injection valve and the cylinder head.
A fuel injection valve 1 is disposed in a receiving conduit 2 of a cylinder head 3 of an internal combustion engine. Fuel injection valve 1 serves to inject fuel into a combustion chamber 4 of the internal combustion engine and is used, for example, in so-called direct injection. Fuel injection valve 1 has at its inflow end 5 , for example, a plug connection to a fuel distribution line 8 that is sealed, for example, by a seal 9 between fuel distribution line 8 and an inflow fitting 10 of fuel injection valve 1 . Fuel injection valve 1 also has an electrical connector 11 for electrical contacting of an actuator of fuel injection valve 1 , for example, an electromagnetic or a piezoelectric or magnetostrictive actuator, for actuation of fuel injection valve 1 .
Fuel injection valve 1 has a valve housing 14 that encompasses an actuator portion 14 . 1 and a nozzle portion 14 . 2 . The cylindrical nozzle portion 14 . 2 has a smaller diameter than the cylindrical actuator portion 14 . 1 of valve housing 14 , so that an annular valve shoulder 15 is formed at the transition between portions 14 . 1 , 14 . 2 . Valve shoulder 15 is, for example, conically beveled radially outward toward actuator portion 14 . 1 with respect to a valve axis 16 , so that a conical region 17 is formed on valve housing 14 . The actuator, which actuates a valve needle, is disposed in actuator portion 14 . 1 . The valve needle extends from the actuator into nozzle portion 14 . 2 of valve housing 14 . The valve needle has, in conventional fashion, a closure element that coacts with a valve seat disposed on the nozzle portion. In order to open the fuel injection valve, the valve needle having the closure element lifts off from the valve seat so that an outlet gap is formed between the closure element and the valve seat, and fuel that travels via fuel distribution line 8 and inflow fitting 10 into valve housing 14 is injected through the outlet gap into combustion chamber 4 .
Receiving conduit 2 is divided into a first conduit portion 2 . 1 for the reception of actuator portion 14 . 1 of valve housing 14 and a second conduit portion 2 . 2 for the reception of nozzle portion 14 . 2 of valve housing 14 . The diameter of second conduit portion 2 . 2 is smaller than the diameter of first conduit portion 2 . 1 . At the transition from the smaller-diameter second conduit portion 2 . 2 into the larger-diameter first conduit portion 2 . 1 , an annular first shoulder 2 . 1 is formed at which, for example, fuel injection valve 1 is mounted. For easier introduction of nozzle portion 14 . 2 of fuel injection valve 1 into second conduit portion 2 . 2 of receiving conduit 2 , second conduit portion 2 . 2 is conically expanded at the end facing toward actuator conduit 2 . 1 A sealing ring 22 provided on nozzle portion 14 . 2 of fuel injection valve 1 seals a gap between second conduit portion 2 . 2 and nozzle portion 14 . 2 of fuel injection valve 1 .
Provided between fuel injection valve 1 and receiving conduit 2 is a damping element 25 that abuts, for example, against first shoulder 21 of receiving conduit 2 and braces fuel injection valve 1 in conical region 17 .
Damping element 25 serves to reduce the transfer of vibration and solid-borne sound from the fuel injection valve to cylinder head 2 of the internal combustion engine. A fuel injection valve, e.g., one having a piezoelectric actuator, can be excited to vibrate strongly, e.g., in a context of multiple injections per injection cycle, so that effective solid-borne sound decoupling between the fuel injection valve and the cylinder head is necessary in order to prevent troublesome noise, proceeding from the fuel injection valve, from being perceived in a vehicle.
According to example embodiments of the present invention, damping element 25 is arranged in plate-shaped fashion. An arrangement that saves a great deal of installation space is thereby achieved. For example, only 1.5 millimeters are available for damping element 25 in the axial direction between first shoulder 21 of cylinder head 3 and fuel injection valve 1 .
Damping element 25 has, according to example embodiments of the present invention, a first portion 26 for bracing or abutment against a shoulder of receiving conduit 2 in cylinder head 3 , for example, first shoulder 21 , and a second portion 27 , angled with respect to first portion 26 , for bracing the fuel injection valve. The plate shape of damping element 25 is created by second portion 27 that is angled with respect to first portion 26 . First portion 26 is arranged, for example, in circular fashion, and second portion 27 in annular fashion. The two portions 26 , 27 are joined integrally to one another. Damping element 25 has a passthrough opening 28 that imparts an annular shape to damping element 25 and through which fuel injection valve 1 can penetrate. Passthrough opening 28 is provided in first portion 26 , so that base 26 of plate 25 has an opening.
Damping element 25 is manufactured, e.g., from metal, for example, steel, and/or plastic. Damping element 25 is fabricated, for example, from sheet metal, for example, having a thickness of 1.5 millimeters. The plate shape of damping element 25 is achieved, for example, by a reshaping method, metal-removing shaping, or a primary forming method.
First portion 26 extends, for example, from second portion 27 radially inward with respect to valve axis 16 . First portion 26 can, however, also be disposed on second portion 27 radially outward with respect to valve axis 16 . The radially inwardly disposed first portion 26 has the advantage, as compared with the radially outwardly disposed first portion 26 , that the shoulder of cylinder head 3 against which the damping element abuts is easier to manufacture.
First portion 26 is, for example, arranged in substantially flat or convex fashion, and abuts with a first support 29 , for example, against the planar first shoulder 21 . The surface area of first support 29 is to be made as small as possible in order to decrease acoustic transmission. First support 29 is, for example, the flat underside, facing toward first shoulder 21 , of damping element 25 . First support 29 can, however, also be constituted by one or more elevations, disposed on the lower side of damping element 25 , that can have any shape and are, for example, rounded in order to achieve good radial displaceability.
Second portion 27 protrudes in collar-shaped fashion from first portion 26 of damping element 25 . For example, second portion 27 is arranged at least substantially conically; a convexity outward toward cylinder head 3 can also be provided. Second portion 27 abuts with a second support 30 , for example, against conical region 17 of valve housing 14 . Damping element 25 is centered with respect to valve axis 16 by conical region 17 of fuel injection valve 1 and by conical second region 27 that coacts with conical region 17 . Second support 30 is part of the upper side, facing toward fuel injection valve 1 , of damping element 25 . One or more elevations are provided, for example, on the upper side of damping element 25 , which elevations form second support 30 and are, e.g., rounded. An annular flange 33 is disposed, for example, as second support 30 on the upper side of damping element 25 . What results is, for example, a linear contact of fuel injection valve 1 against damping element 25 , thus achieving gimbaled mounting.
Forces proceeding from fuel injection valve 1 are transferred via second support 30 , collar 27 of damping element 25 , and first support 29 to cylinder head 3 . There exists between first support 29 and second support 30 not only an axial spacing but also a radial spacing, which represents a lever arm. This lever arm of collar 27 results in an axial elasticity of damping element 25 with respect to valve axis 16 , which elasticity brings about a solid-borne sound damping in that the periodic switching pulses of the actuator of fuel injection valve 1 are transferred in greatly attenuated fashion via first shoulder 21 to cylinder head 3 . Very small relative motions occur between fuel injection valve 1 and damping element 25 at second support 30 , so that additional vibration damping is accomplished by friction. The larger the lever arm is dimensioned, the greater the elasticity of damping element 25 .
The transition from first portion 26 to second portion 27 can be sharp-edged or rounded.
Because of the planar arrangement of first shoulder 21 , damping element 25 disposed in receiving conduit 2 is displaceable radially with respect to valve axis 16 . The radial displaceability of damping element 25 is necessary because, as a result of tolerances, a conduit axis 31 of nozzle portion 2 . 2 of receiving conduit 2 and an inflow axis 32 of fuel distribution line 8 do not always align.
FIG. 2 shows a damping element according to an example embodiment of the present invention, in a detail II according to FIG. 1 .
In the context of the damping element according to FIG. 2 , parts that remain the same, or function in the same manner, as compared with the fuel injection valve according to FIG. 1 are labeled with the same reference characters.
The raised flange 33 on an end of second portion 27 facing away from first portion 26 is disposed on the upper side facing toward fuel injection valve 1 .
FIG. 3 shows a damping element according to an example embodiment of the present invention, in a detail III according to FIG. 1 .
In the context of the damping element according to FIG. 3 , parts that remain the same, or function in the same manner, as compared with the fuel injection valve according to FIG. 1 and the exemplary embodiment according to FIG. 2 are labeled with the same reference characters.
The damping element according to FIG. 3 differs from the damping element according to FIG. 2 in that the longitudinal extension of collar 27 is greater. The rigidity of damping element 25 is thereby increased. Flange 33 is disposed not at an end, facing away from first portion 26 , of second portion 27 , but instead at approximately half the longitudinal extension of collar 27 on the upper side facing toward fuel injection valve 1 .
FIG. 4 shows a damping element according to an example embodiment of the present invention, in a detail IV according to FIG. 1 .
In the context of the damping element according to FIG. 4 , parts that remain the same, or function in the same manner, as compared with the fuel injection valve according to FIG. 1 and the exemplary embodiments according to FIGS. 2 and 3 are labeled with the same reference characters.
The damping element according to FIG. 4 differs from the damping elements according to FIG. 2 and FIG. 3 in that the damping element is manufactured from a composite material made up of two cover panels 35 and an elastic intermediate layer 36 provided between cover panels 35 . Cover panels 35 and intermediate layer 36 are in each case joined fixedly to one another. In a context of flexural vibrations of damping element 25 , cover panels 35 shift relative to one another with the result that periodic shear deformations occur in elastic intermediate layer 36 . The internal friction in elastic intermediate layer 36 causes vibratory energy to be lost as mechanical energy, so that vibration damping, and therefore solid-borne sound damping, is achieved.
First portion 26 of damping element 25 is not planar but instead convex toward first shoulder 21 . Second portion 27 is arranged in substantially conical and additionally convex fashion. Adjoining second portion 27 radially outward is, for example, a second shoulder 34 . The transition from second portion 27 to second shoulder 34 is, for example, rounded.
The composite material, which is at first planar in its initial shape, is converted into a plate shape, for example, by reshaping.
It is also possible to dispose multiple damping elements 25 according to the exemplary embodiments presented, one above another in layered fashion, in order to achieve even better noise damping. | Damping elements for a fuel injection valve insertable into a receiving conduit of a cylinder head of an internal combustion engine are disposed between a valve housing of the fuel injection valve and a wall of the receiving conduit of the cylinder head. These damping elements, inter alia, decrease acoustic transfer from the fuel injection valve to the cylinder head. It is disadvantageous that conventional damping elements require a great deal of axial installation space with respect to a valve axis and have comparatively high manufacturing costs. With the damping element according to example embodiments of the present invention, the installation space required is reduced. Provision is made, according to example embodiments of the present invention, for the damping element to be in plate-shaped fashion. | 5 |
BACKGROUND OF THE INVENTION
This invention is directed to an improved ice resurfacing machine blade holder for holding disposable blades.
Ice resurfacing machines were developed several decades ago for refurbishing the surface of ice on a skating rink, hockey rink, or other recreational ice surfaces. A modern ice resurfacing machine has the capacity to plane a rough surface of ice with a blade, sweep or vacuum up the ice-shavings planed off the surface of the ice, wash and squeegee the surface, and finally, coat the surface with a light film of water which immediately freezes to form a new ice surface. Basically, the ice resurfacing machine is a self-propelled vehicle having a dump tank for disposing of ice and snow lifted from the surface of the ice, a water tank for supplying fresh water for the surface of the ice, and a sled. Mounted on the sled are the necessary hardware items for shaving the ice, removing the shavings, washing and squeegeeing the ice, and then rewetting the ice.
It is important to condition the ice surface for several reasons. The ice is used for skating in one form or the other. Iceskates have sharp edges which cut into and gouge the surface of the ice caused by the wear and tear of the iceskates moving over the ice. Further, in order to control the energy costs in maintaining an artificial ice surface, it is necessary to maintain proper thickness of the ice.
Since ice is a hard solid, it is abrasive to the blades utilized to shave and plane the ice and it wears down the blade's cutting edge. A dull blade will not properly shave the ice. Use of a dull blade can result in a rough and wavy surface and improper pickup of snow off the ice surface.
Since most ice rinkgs and other ice surfaces are quite large, the ice resurfacing machine must be of a sufficient size so as to be able to traverse over the totality of the surface of the ice in a reasonable amount of time. This requires a certain width to the ice machine such that the width of the resurfacing path of the ice resurfacing machine is sufficiently large in order to resurface the ice in a minimum number of traverses back and forth across the ice surface. Generally, an ice surfacing machine will resurface a width of ice approximately five to seven foot wide. In resurfacing this path width of ice, it is necessary for the ice resurfacing blade to be maintained absolutely fixed across its total width such that the ice will be resurfaced in a smooth plane across the total width of the path of the ice resurfacing machine.
Initially, a single large heavy blade was utilized on ice resurfacing machines. As in explained in the specification of U.S. Pat. No. 3,917,350, when these older monolithic blades were utilized, generally four blades were needed. Two to be sent out to be resharpened, one on the machine for use, and one for replacing as soon as the one of the machine became dull. These older blades weighted in excess of fifty pounds. This large, heavy blade had to be attached and detached from the bottom of the sled portion of the ice resurfacing machine. Generally, the sled portion of the ice resurfacing machine can be raised approximately ten to twelve inches off the surface of the ice. While this allows for a certain amount of working room, it certainly is not a convenient work space. Because the blades were very heavy and had a very sharp edge thereon, and because of the limited space in which to work, for the older monolithic blades at least two men were required for the detaching and remounting of the blade on the ice resurfacing machine.
U.S. Pat. No. 3,917,350 describes the use of disposable light weight blades which are held in a fixture which is attached to the sled portion of an ice resurfacing machine. While several embodiments of holding fixtures are described in this patent, problems have been encountered with each of these.
The disposable blades for use on ice resurfacing machines are lightweight elongated flexible stainless steel blades having a sharpened edge thereon. Since it is absolutely mandatory that these be held in a rigid position beneath the sled of the ice resurfacing machine, mounting them can be equated to the problem of fixing an extremely sharp blade in a six foot wide vice which must be lightweight, perfectly rigid, but at the same time inexpensive and easy to manipulate. As is evident, this is a very exacting and difficult set of criteria to meet.
Problems have been experienced in utilizing prior known blade holders. These problems include the difficulty and consequently the expense in machining the components to the shape necessary for functioning of these holders. Aside from the manufacturing difficulties and cost, in acutal use, the prior blade holders for disposable blades are, on occasion, subject to warpage and misalignment of their component parts. Furthermore, in one commercial embodiment of these blade holders, the same set of bolts are utilized to both attach the blade holder to the ice resurfacing machine and to grip or attach the blade in the blade holder. Thus, in changing the blade, the personnel not only has to content with inserting a very sharp blade into the blade holder, but also have to contend with portions of the blade holder moving with respect to the machine, which complicated the insertion and removal of the blades.
In view of the above, it is evident that there exists a need for new and improved blade holders for use in holding disposable blades on ice resurfacing machines. It is, therefore, a broad object of this invention to provide such new and improved blade holders for ice resurfacing machines. It is a further object of this invention to provide a blade holder for an ice resurfacing machine which allows for quick and convenient replacement of blades without requiring extended expenditure of expensive labor time in doing so. It is a further object to provide a blade holder for an ice resurfacing machine which because of the engineering principles inherent therein is capable of being economically manufactured but is also capable of a long and useful lifetime.
These and other objects as will become evident from the remainder of this specification are achieved in an ice resurfacing machine blade holder which comprises: a blade attachment member sized and shaped so as to have an elongated transverse dimension sufficient to extend across the width of the resurfacing path of the ice resurfacing machine. The blade attachment member has a forward edge and a bottom surface and a top surface all of which extend across the elongated transverse dimension of the attachment member. The blade attachment member includes an inverted "V" shaped groove extending into the bottom surface across the elongated transverse dimension of the attachment member along the forward edge of the attachment member. The "V" shaped groove has an essentially flat planar blade abutting surface and an essentially flat planar retaining element abutting surface with the blade abutting surface positioned towards and intersecting the forward edge of the blade attachment member and with the blade abutting surface located between the forward edge and the retaining element abutting surface. The blade abutting surface and the retaining element abutting surface intersecting each other at an obtuse angle. It further includes a retaining element which is essentially triangular in shape in cross section and has an elongated transverse dimension essentially equal to the elongated transverse dimension of the attachment member. The retaining element has an essentially flat planar blade engaging wall and an essentially flat planar attachment member engaging wall and a bottom wall each of which intersect the others to form the triangular cross sectional shape. The blade engaging wall and the attachment member engaging wall intersecting each other at an obtuse angle equal to or essentially slightly greater than the angle of intersecting of the engagement member blade abutting surface and retaining element abutting surface. The retaining element is positional on the attachment member with the attachment member engaging wall mating with the retaining element abutting surface and the blade abutting surface and the blade engaging wall being spaced apart from one another in an essentially parallel alignment to form a cavity between the attachment member blade abutting surface and the retaining element blade engaging wall. The essentially parallel alignment of blade abutting surface and the blade engaging surface shape the cavity so as to accept a disposal ice resurfacing blade within the cavity. A locking means is included for retaining the retaining element in the mating position against the attachment member whereby the disposal ice resurfacing blade is capable of being temporarily fixely retained in the cavity.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention will be better understood when taken in conjunction with the drawings wherein:
FIG. 1 is a side elevational view of a typical known ice resurfacing machine;
FIG. 2 is a side elevational view of a known blade holder and disposable blade as attached to a component mounting part of a typicial ice resurfacing machine as for instance the machine of FIG. 1;
FIG. 3 is an isometric view of a first embodiment of a blade holder of this invention;
FIG. 4 is an isometric view of a further embodiment of a blade holder of this invention;
FIG. 5 is a side elevational view in partial section about the line 5--5 of FIG. 4;
FIG. 6 is a diagrammatical view of certain components of a further embodiment of the invention;
FIG. 7 is a fragmentary isometric view of a blade utilized in the embodiment of FIG. 6; and
FIG. 8 is a fragmentary side elevational view in partial section about the line 8--8 of FIG. 3.
This invention utilizes certain principles and/or concepts as are set forth in the claims appended hereto. Those skilled in the machine arts will realize that these principles and/or concepts are capable of being utilized in a variety of embodiments which may differ from the exact embodiment utilized for illustrative purposes herein. For this reason this invention is not to be construed as being limited solely to the illustrative embodiments, but should only be construed in view of the claims.
DETAILED DESCRIPTION OF THE INVENTION
Several ice resurfacing machines are known. Certain of these machines are described in U.S. Pat. Nos. 2,763,939; 3,622,205; and 3,917,350. Each of these is assigned or owned by the assignee of this invention, and the entire disclosures of each of these patents is herein incorporated by reference.
A complete understanding of all of the detailed parts of an ice resurfacing machine is not necessary for the understanding of this invention. Reference is made to the above referred to patents for specific understanding of ice resurfacing machines. For the purposes of this invention, it is sufficient to note that an ice resurfacing machine such as the machine 10 of FIG. 1 will include a sled 12 as a component part thereof. Mounted within the interior of the sled is a blade holding assembly 14. For details of such a blade housing assembly, reference is made to the disclosure of U.S. Pat. No. 3,917,350.
Referring to FIG. 2, a typical prior known blade holder 16 is shown. A support member 18 forms a component part of the blade holding assembly 14 of FIG. 1. Fitting beneath the support member 18 is a clamp bracket 20. The clamp bracket 20 has a forward curving front portion 22 which terminates in a leading edge 24. Located beneath the clamp bracket 20 is a holder 26. The holder 26 has a land 28 on the rear portion thereof and includes a shoulder 30 from which a wedge surface 32 extends. A disposable blade 34 rests on the wedge surface 32 abutting against the shoulder 30. The leading edge 24 of the bracket 20 rests on top of the blade 34. A series of screws 36 clamp the holder 26 to the clamp bracket 20, and, in turn, both of these elements to the support member 18. The blade 34 is pinched between the wedge surface 32 of the holder 36 and the leading edge 24 of the bracket 20.
The land 28 in essence serves as a fulcrum. The screw 36 rotates the holder 26 about the land 28 so as to squeeze the blade into the leading edge 24 to hold it in position. As is evident, the lever arm identified by the numeral 38 between the land 28 and the leading edge 24 is quite long compared to the length of the blade 34 which is held against the wedge surface 32. Further, the back edge of the blade abuts against the shoulder transmits all its force to the holder 26. When force is applied to the cutting edge of the blade 34, a component vector of this force is transmitted to the shoulder 26 exerting a rotational force to the holder 26 tending to rotate it about the land 28. The screw 36 must counteract this rotational force which is amplified by the long lever arm 38.
The shape of the leading edge 24 is difficult to achieve during manufacture of the clamp bracket 20. Furthermore, since the screw 36 not only clamps the blade 34 into the holder 26 and the bracket 20, but also holds these two components to the support member 18, during exchange of a blade 34, the operator must content not only with removing and inserting the blade 34, but with dropping of both the holder 26 and bracket 20 downwardly from the support member 18.
Referring now to FIG. 3 there is shown a first blade holder 40 of the invention. The blade holder 40 has two component parts, an attachment member 42 and a retaining member 44. Further shown in FIG. 3 is a disposable blade 46. As is evident from FIG. 3, the disposable blade 46 is retained in the attachment member 42 by the retaining member 44.
Both the attachment member 42 and the retaining member 44 are formed as unified one piece extrusions. Preferably they are formed of aluminum or some other light weight, strong alloy. As is evident from their shape in FIG. 3, they have a consistent cross sectional shape along the totality of these elements allowing them to be conveniently and economically formed by extrusion.
The width of the attachment member 42 as shown by the line 48 is sufficient such that the attachment member 42 extends across the total resurfacing path width made by the ice resurfacing machine. Typically this width would be of the order of about 90 inches. The length of the attachment member 42 shown by the line 50 in the figure is of the order of about 5 inches and the height, as shown by the line 52, is approximately three-fourths of an inch. As shown in the figures, the dimensions are not to scale. The same is true with respect to the scale of FIG. 4.
The attachment member 42 includes a plurality of attaching holes 54 which are utilized to mount the attachment member 42 to a further blade holding assembly such as the assembly 14 shown in FIG. 1 on the ice resurfacing machine 10. A groove 56 is formed on the bottom surface 58 of the attaching member 42. The groove 56 is cut with side walls which are perpendicular to the bottom of the groove. This allows for the location of square headed nuts in the groove 56 with the side walls of the groove 56 serving to inhibit the rotation of these square nuts. To mount the attaching member 42 to a typical blade holding assembly 14, appropriate bolts (not seperately numbered or shown) would be passed through the blade holding assembly 14 downwardly through the attaching holes 54 and threaded into the square headed nuts (also not seperately numbered or shown) which would be located within the groove 56.
The attachment member 42 has a retaining surface 60 and a blade abutting surface 62 which together form an inverted "V" shaped groove indenting into the bottom surface 58 of the attachment member 42. This accepts the triangular cross sectional shape of a retaining member 44.
The retaining member 44, as is also evident in FIG. 3, is triangular in shape in cross section. Further, it is elongated in width such that it essentially has the same width as the attachment member 42.
The triangular shape of the retaining member 44 is formed by an attaching wall 64 and a blade abutting wall 66 together with a bottom wall 68. When the attaching wall 64 on the retaining member 44 is mated against a retaining surface 60 on the attaching member 42, the retaining member 44 is in a position so as to space a blade abutting surface 62 on the attaching member 42 away from a blade abutting wall 66 on the retaining member 44 such that a blade cavity 70 is formed. An elongated section of the disposable blade 46 is positionable within this blade cavity 70.
With reference now to FIG. 8, located on a top surface 74 of the attachment member 42 is a further elongated groove 76 whose sides are perpendicular to its flat bottom. Thus, this groove is also sized and shaped so as to accept square headed nuts 78. A plurality of holes collectively identified by the numeral 80 pass from the bottom of the groove 76 through the attaching member 42 into the retaining surface 60. A like plurality of holes 82 are drilled in the retaining member 44. The holes 82, however, are cut slightly oversized with respect to the holes 80. Further, the openings of the holes 82 in the bottom wall 68 are countersunk.
A plurality of bolts collectively identified by the numeral 84, only one of which is shown in FIG. 8, pass through the holes 82 in the retaining member 44, through the holes 80 and screw into the nuts 78. Since the holes 82 are oversized with respect to the shank size of the bolts 84 and the holes 80, and since the surface of the attaching wall 64 and the retaining surface 60 are at an angle with the respect to the axial axis of the hole 80, as the bolts 84 are tightened to the nuts 78 they cause the retaining member 44 to slide to the right as viewed in FIG. 8 along the surface 60 of the attachment member 42. This brings the blade abutting wall 66 toward the blade abutting surface 62 decreasing the width of the cavity 70. This squeezes against the sides of the blade 46 locking it into the cavity 70 to fixedly hold it in position between the retaining member 44 and the attachment member 42.
As will be discussed in greater detail below, the angle the retaining surface 60 makes with the blade abutting surface 62 is essentially the same as the angle between the attaching wall 64 and the blade abutting wall 66. Because of this, the blade abutting surface 62 is essentially parallel to the blade abutting wall 66. As the retaining member 44 is slid to the right in FIG. 8 upon tightening of the bolts 84 to the nuts 78, this parallel relationship between the surface 42 and the wall 66 is maintained. Because of this, the blade 62 is gripped essentially along the totality of it's surface which is located within the cavity 70 and not simply along an edge as per prior known blade holders. This results in an even force applied to the blade 46, assisting in preventing warpage of the blade 46, and the elimination of uneven stresses to both the attachment member 42 and retaining member 44.
The blade abutting surface 62 extends out of the forward end of the attachment member 42 cutting through this forward end at a forward edge 86 which extends across the complete width of the attachment member 42. The dimension of the blade 46 is chosen such that it is slightly wider (as measured from its cutting edge to its back edge) than that of the cavity 70 such that the cutting edge of the blade 46 extends a slight increment out from the forward edge 86 of the attachment member 42.
A further groove 88 is formed in the attachment member 42 wherein the retaining surface 60 intersects the blade abutting surface 62. The back edge 90 of the groove 88 is essentially perpendicular to the blade abutting surface 62 and serves to receive the back edge 72 of the blade 46. Since this back edge 90 of groove 88 is formed in the attaching member 42, forces transmitted up through the blade from its cutting edge to its back edge 72, are directly transmitted to the attachment member 42 and not to the retaining member 44. The only force transmitted to the retaining member 44 would be a force tending to rotate it away from the retaining surface 60 against the opposing force introduced by the bolts 84 threading into the nuts 78. Since the maximum lever arm of the retaining member 44 can only be as long as its bottom wall 68, this lever arm is much smaller than in prior known devices and, thus, little or no forces are carried by the retaining member 44. Because of this, it can be reduced in size with respect to prior known components which were utilized to retain a blade against a further component.
Because of the shape and construction of the attaching member 42 and retaining member 44, for a blade holder 40 of approximately 80 inches width, the totality of the weight of the holder including the blade will only be on the order of fifteen pounds. This is a substantial reduction in weight compared to other prior known ice resurfacing machine blades.
Referring now to FIGS. 4 and 5, a further embodiment of the invention is shown. In this embodiment, a blade holder 92 is illustrated. The blade holder 92 is similar in construction to the blade holder 40 with the exception that it does not include the groove 76. Instead of utilizing square nuts 78 on its upper surface, holes 94 equivalent to the holes 80 of the bade holder 40, are drilled only part way into an attaching member 98, and a threaded insert 100 is force-fitted into the attaching member 98. Appropriate bolts 102 can then be utilized to connect a retaining member 96 to the attaching member 98 in the manner described for the embodiment of FIG. 3. Threaded inserts 104 are also force-fitted into holes 106 to receive connecting bolts 108 for attachment of attachment member 98 to a support member 110.
Utilizing the embodiment of FIGS. 4 and 5 for illustration purposes, during cutting or shaving of the ice, preferably the blade 112 is held at an angle of about 32° to the ice surface. Because of this, the angle between the bottom wall 114 and the blade abutting wall 116 of the retaining member 96 is a small acute angle, as for instance at about 24°. The angle between the bottom wall 114 and the attaching wall 118 is also a small acute angle, as for instance about 18°. The angle between the blade abutting wall 116 and the attaching wall 118 is a large obtuse angle, as for instance about 138°. As such, the ratio of the length of the blade abutting wall 116 to the attaching wall 118 to the bottom wall 114 is about 1.5:2:3. These approximate ratios allow for sliding of the retaining member 96 on the attachment member 98 when under a force applied by the bolts 102 to the retaining member 96 so as to squeeze or pinch the blade 112 between the attachment 98 and the retaining member 96.
As per the embodiment of FIG. 3, the embodiment of FIGS. 4 and 5 also include a groove 122 formed in the attachment member 98. The groove 122 has a back wall 124 which is perpendicular to the blade 112 abutting surface 126 such that the force transmitted along the blade directly from its tip to its rear edge is taken up directly by the attaching member 98.
In FIG. 6 a further embodiment is shown. This embodiment differs from the embodiments of FIGS. 3, 4, and 5 in that in this embodiment a hole 128 passing through an attachment member 130 and a corresponding hole 132 passing through a retaining member 134 are positioned so as to go through the intersecting point of a blade abutting surface 136 and a retaining surface 138 on the attachment member 130 and a blade abutting wall 140 and an attaching wall 142 on the retaining member 134. As with the prior embodiments, a groove 144 can be located at the line of intersection of the surfaces 136 and 138.
For use with the embodiment of FIG. 6, a blade as is shown in FIG. 7 would be utilized. The blade 146 shown in FIG. 7 has a cutting edge 148 and includes a plurality of notches 150 located in its rear edge 152. The notches 150 are sized and shaped so as to align with the holes 128 and 132 passing through the attaching member 130 and retaining member 134 of FIG. 6.
In the embodiments of FIGS. 6 and 7, an appropriate bolt (not numbered or shown) passing through the holes 132 and 128 would be located within the notch 150 and would urge the retaining member 134 against the blade 146 to hold it against the attachment member 130.
Preferably in each of the embodiments shown, the angle between the blade abutting surface and the retaining surface on each of the attachment members would be the same as the angle between the blade abutting wall and attachng wall on each of the retaining members shown. This would assure that when the retaining wall was mated against the abutting wall, that the blade abutting surface would be parallel to the blade abutting wall. However, to account for manufacturing, tolerances in machining the extrusion fixture, the angle on the retaining member between the blade abutting wall and the attaching wall, if not made exactly the same as the angle between the blade abutting surface and the retaining surface on the attaching member, would be made slightly larger than this angle. When so formed, the blade abutting surface and the blade abutting wall would not be perfectly parallel to one another but they would be slightly closer together near the forward edge of the attachment member. Because both abuttment member and the retaining member are thinner near the forward edge, any slight flexure or cold flow of the casting material near this thin edge should tend to reshape these components back towards a parallel fit between the blade abutting surface and the blade abutting wall and the side surfaces of the blade. | A blade holder for holding a disposable ice shaving blade on an ice resurfacing machine has an attachment member which is attached to an appropriate support member on the ice resurfacing machine. The attachment member has an elongated "V" shaped groove which extends across the transverse width of the attachment member. A triangular shaped retaining member mates against a surface in the ∓V" shaped groove on the attachment member. A surface on the attachment member and a wall on the retaining member which are spaced apart from each other in a parallel relationship when the retaining member mates with the attachment member, form a cavity for excepting and retaining a disposable ice shaving blade. The retaining member is connected to the attachment member utilizing a plurality of attaching elements such as appropriate bolts or the like. These attaching elements are independent from the structure which is utilized to attach the attachment member to the appropriate support member on the ice resurfacing machine. | 4 |
FIELD OF THE INVENTION
This invention relates to oilfield completion systems and, in particular, to a wellhead completion system having a metal-to-metal sealing arrangement for control lines installed on a surface wellhead.
BACKGROUND OF THE INVENTION
For many surface and subsea oil and gas wells, a series of pipes, fittings, valves, and gauges are used on a wellhead to control the flow and achieve well completion. A Christmas or production tree is generally attached to the wellhead and the pipes, fittings, valves and gauges are typically routed and connected to the tree. One, or a plurality of, penetrators or stems, may be installed in a Christmas tree to engage components installed within the wellhead, such as a tubing hanger. The penetrators may be horizontal, vertical, or at other angles, and allow downhole control lines, such as electrical and/or hydraulic, to be routed through the tree and tubing hanger sidewalls and be routed down to components below the wellhead.
Subsea horizontal tree tubing hangers generally utilize a sealing arrangement for control lines that rely on the weight of completion tubing to activate the device sealing mechanism. On conventional surface wellhead applications, however, there is insufficient space available on most completions to incorporate this sealing arrangement
Well completions are now using an increasing number of downhole control lines with some operators now requesting up to eleven separate control lines. As explained above, the conventional method of exiting a plurality of control lines through the wellhead usually requires that the control line pass through a tubing hanger in a continuous manner and then exit through the wellhead body. However, large numbers of control lines make this conventional exit arrangement complex and difficult to complete within the limited space available in the wellhead upper bowl area. Fitting multiple control lines in the limited space currently available is difficult and labor intensive, with control lines frequently bent in awkward directions with some having to physically cross over others. Control lines are thus frequently damaged. Thus, little space on this particular completion arrangement is left to provide “spare” length on the control line.
Further, if any problems are encountered during the control line termination phase through the wellhead, it may be necessary to pull the completion, which is an expensive and time-consuming exercise involving significant rig down-time.
A need exists for a technique to allow sufficient clearance for a plurality of downhole control lines at a well.
SUMMARY OF THE INVENTION
In an embodiment of the invention, a well completion includes a wellhead, a control line assembly, and a tubing hanger. The wellhead may have a generally cylindrical body with a bore. The control line assembly may include a cylinder and a main housing assembly with a flange with a bolt pattern at one end for mounting to the wellhead body via bolts. The control line assembly may further include a passage and a metal-to-metal seal. The passage may be a tube or stem within the cylinder that has an inlet at an exterior end and extends into the wellhead bore at another end. A split lockout ring provides a positive lock to the passage. A plurality of control line assemblies may be mounted to the wellhead. The well completion described herein may also be used in production casing hangers to run control lines down through a production annulus.
The tubing hanger may have a plurality of vertical passages formed in a sidewall of the hanger that communicates with well components, such as valves or instrumentation devices, within the well and below the tubing hanger. Further, a plurality of radial passages communicate with the vertical passages at one end and communicate radially with an outer surface of the tubing hanger. The tubing hanger may be landed within the bore of the wellhead and oriented such that the radial passages in the tubing hanger align with each of the passages of each of the control line assemblies.
This arrangement on the wellhead of the control line assemblies advantageously provides sufficient height and clearance to allow for the installation of a plurality of control lines entering into the tubing hanger and exiting from the wellhead.
This invention provides several additional advantages. The invention advantageously overcomes the problem of bending and fitting multiple control lines in the limited space available by moving the exit point down to the main wellhead body and creates multiple control line entry points on the tubing hanger body with a minimal height increase. The multiple control lines can be accommodated in a “single band” around the tubing hanger and wellhead body thereby minimizing any height impact. In addition, safety for personnel is improved by this invention given that work around an open well, which may involve working underneath suspended BOP stacks, is minimized. From an operational safety standpoint, hydraulic control line communication can be advantageously achieved immediately after the tubing hanger has landed in the wellhead without the need to break the BOP stack and thereby maintaining complete well control. Further, as the mating stem seal surface on the tubing hanger body is below the main outer diameter of tubing hanger body, seal surface is protected from damage during tubing hanger installation operations through a BOP stack. This invention further reduces risk of control line damage and reduces the risk of the cost and downtime related to pulling a completion. Further, the invention provides metal-to-metal sealing, which is particularly suitable for critical and high pressure/high temperature applications, is tamper-proof, and reduces rig down time during the control line termination process. Further, the invention provides immediate communication with downhole hydraulic lines once the tubing hanger is landed. The control line assemblies can also be retrofitted onto an existing wellhead as required by the number of downhole control lines required. The invention also provides a lower cost alternative to comparable third-party exit valve arrangements.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 , is a perspective view of an embodiment of a wellhead, in accordance with the invention;
FIG. 2 , is a top view of the wellhead of FIG. 1 ;
FIG. 3 , is a partial sectional view of an embodiment of a control line assembly mounted to the wellhead, in accordance with the invention; and
FIG. 3A , is an enlarged view of a portion of FIG. 3 , in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a perspective view of an embodiment of a generally cylindrical wellhead 10 having a bore 12 , that may be installed on a surface or subsea well. In this embodiment, the wellhead 10 further has a body or wellhead body 14 with a sidewall 16 . The sidewall may have a radial thickness defined generally by a difference between an outer surface of the body 14 and an upper connection 18 . The upper connection 18 shown has a generally cylindrical shape, although the upper connection can take the form of a flange, and extends upward from the body 14 of the wellhead 10 .
Continuing to refer to FIG. 1 and also FIG. 2 , a control line assembly 24 , which may be one of a plurality of assemblies, is mounted to the body 14 of the wellhead 10 via bolts 26 . The bolts 26 pass through bolt passages (not shown) in a flange 28 on a mounting end of the control line assembly 24 and further engage corresponding bolt passages (not shown) formed in the body 14 of the wellhead 10 . The flange 28 of the control assembly 24 is received by a recess 30 formed on the outer surface of the wellhead body 14 . The flange 28 may be a standard API flange or some form of compact flange design. A seal ring 29 ( FIG. 3 ) may be located between the flange 28 and the wellhead body 14 to effect a seal. In the embodiment of FIGS. 1 and 2 , the control line assembly 24 extends radially outward from the wellhead 10 and horizontally. However, the assembly 24 could also extend outward at an angle from horizontal. The number of control line assemblies 24 and other connections may vary with the requirements of the well completion. The control line assembly 24 and instrumental signal port 32 will be explained further below.
Referring to FIG. 3 , a portion of the wellhead 10 having the control line assembly 24 is illustrated in side sectional view. The control line assembly 24 has an outer cylinder 40 fitted with an end cap 41 to define, in part, a hydraulic cylinder. A penetrator or stem 42 having an axial passage 43 with an inner diameter is located within the cylinder 40 and has an indicator or recess 44 at an outer end 46 . The indicator 44 is formed on a circumferential periphery of the stem 42 and indicates when the stem 42 is properly installed within the wellhead body 14 . The indicator 44 is on a portion of the stem 42 that projects past the end cap 41 . The stem 42 has a control line inlet 48 at the outer end 46 that may allow connection to control sources such as a hydraulic supply. A horizontal passage 50 traverses the wellhead sidewall 16 to communicate the outer surface of the wellhead body 14 with the bore 12 . Horizontal passage 50 allows a penetrating end 52 of the stem 42 to pass through wellhead sidewall 14 . In this embodiment, passage 43 increases to a diameter 54 within the penetrating end 52 of the stem 42 .
Continuing to refer to FIG. 3 , the penetrating end 52 of stem 42 has a nose arrangement 60 terminating at penetrating end 52 . Nose arrangement 60 has a wave-like profile 61 which is located within horizontal passage 50 . The nose arrangement 60 of the stem 42 corresponds with bore 12 of the wellhead 10 and interfaces with an exterior surface 62 of a tubing hanger 64 shown landed within the wellhead 10 . When energized against the tubing hanger 64 interface, the nose arrangement 60 creates a metal-to-metal seal. In this embodiment, tubing hanger 64 is properly aligned with the control line assembly 24 via a key 66 located at a lower portion of tubing hanger 64 . The key 64 is outwardly biased by at least one spring 68 . Key 66 is retracted until the key is received by a corresponding recess 70 formed in wellhead bore 12 . Other types of alignment mechanisms may also be utilized. When tubing hanger 64 is properly aligned within the wellhead 10 , a horizontal hanger passage 72 registers with nose arrangement 60 to establish communication with passage 43 of stem 42 . An annular metal seal 74 is located within a seat 76 formed at nose arrangement 60 to seal at interface formed by nose arrangement and horizontal hanger passage 72 . In this embodiment, horizontal passage 72 intersectingly communicates with a vertical hanger passage 80 . Vertical hanger passage 80 further communicates with a lower surface 82 of tubing hanger 64 to allow communication with a line 84 that may connect to an inlet 86 located at lower end of vertical hanger passage. Line 84 may serve various types of components located below the hanger 64 .
Continuing to refer to FIG. 3 , a hydraulic piston 100 in this embodiment is formed integral with the stem 42 and allows the stem to reciprocate axially within a distance defined by end cap 41 and a stop 102 that projects radially inward from cylinder 40 . As significant force is required to activate the nose arrangement 60 and set the metal-to-metal seal at the tubing hanger 64 , a chamber 104 may be pressurized to deliver a distributed force to a back face of piston 100 to move piston, and thus stem 42 , forward into sealing engagement with tubing hanger 64 . The chamber is defined by the cylinder 40 , end cap 41 , stop 102 , and hydraulic piston 100 . Chamber 104 may also be pressurized on front face of piston 100 by an external source (not shown) to cause piston to retract, allowing retrieval of the tubing hanger 64 . When the stem 42 is in a fully engaged position with tubing hanger 64 , indicator mark 44 on the outer end 46 provides visual indication to the operator that the metal-to-metal seal is set.
Continuing to refer to FIG. 3 , once stem 42 is set against tubing hanger 64 , the stem 42 may be positively locked in place by a split lockout ring 106 to thereby prevent loss of sealing. The split lockout ring 106 has a toothed inner profile 108 and a tapered rear surface 110 . The toothed inner profile 108 lockingly engages a corresponding mating profile 112 formed on an outer surface of stem 42 . Mating profile 112 may also have a toothed profile. Tooth profiles on the split lockout ring 106 and mating profile 112 may have varying depths depending on the application. The split lockout ring 106 is held off stem 42 by a hydraulic lockout piston 114 while stem 42 is energized and set. This hydraulic locking mechanism acts as a safety measure in that there are no external components which can be tampered with or accidentally activated to unset the locking mechanism. An operator must physically connect a hydraulic supply to an inlet port (not shown) on the control line assembly 24 and apply pressure. Once stem 42 is set against the tubing hanger 64 , pressure is released from the lockout piston 114 and the split lockout ring 106 is then driven down onto mating tooth profile 112 by a wave spring 116 to positively lock the stem 42 in place. Wave spring 116 is located at one end to split lockout ring 106 and at a second end to an internal housing 118 concentric with the stem 42 . Wave spring 116 has a flat face at each end to engage mating component faces.
Continuing to refer to FIG. 3 , a metal-to-metal seal 130 may also be effected between stem 42 and a main housing assembly 134 and a flexible metal seal lip 135 which sealingly engages outer surface of the stem as shown in FIG. 3A . The seal lip 135 is in interference contact with the stem 42 , with this sealing arrangement further enhanced by any pressure present in the wellhead bore 12 . An inside surface of the lip 135 may have a plurality of sealing lands or raised faces which initially form an interference seal and then progressively increases the sealing contact as the pressure in the wellhead bore 12 increases. The seal lip 135 partially defines an inner dynamic seal 137 ( FIG. 3A ). This is achieved by a metal seal ring 132 concentric with stem 42 that sealingly engages the main housing assembly 134 to form outer static seal 139 ( FIG. 3A ). In this embodiment, a stem seal area 136 of outer surface of stem 42 may be have a tungsten carbide coating so the stem seal area 136 can withstand forces applied by the flexible metal seal lip 135 that may result in galling between the stem 42 and flexible lip. Metal-to-metal seal 130 of stem 42 with main housing assembly 134 and metal-to-metal seal of nose arrangement 60 with tubing hanger 64 may both be verified via a test port (not shown) on the main housing assembly 134 . The outer static seal 139 utilizes a metal-to-metal seal ring profile which effects a seal by elastic deformation of a seal lip opposite the metal seal lip 135 when made-up to the main housing assembly 134 . In this embodiment, the metal-to-metal seal assembly is installed in the main housing body 134 and then the internal housing 118 is threaded in with this process energizing the outer static seal 139 . The stem 42 is then inserted through the inner dynamic seal 135 followed by remaining components, including 116 and 106 .
In one example, during installation of the control line assembly 24 , the control line assembly is mounted to wellhead body 14 such that the penetrating end 52 of the stem 42 enters the horizontal passage 50 formed in the wellhead sidewall 16 . To energize and set the metal-to-metal seal between the nose arrangement 60 and previously landed tubing hanger 64 via annular metal seal 74 , chamber 104 is pressurized at a front face of piston 100 to move piston, and thus stem 42 , forward. Sufficient force is generated by piston 100 to force metal seal 74 into sealing engagement with tubing hanger 64 . To retract stem 42 and allow retrieval of tubing hanger 64 , chamber 104 may be depressurized or pressurized on front face of piston 100 to cause piston to retract as a force exerted by the wave spring 116 drives the split lockout ring 106 and lockout piston 114 back to the original, deenergized position. When the stem 42 is in a fully engaged position with tubing hanger 64 , indicator mark 44 on the outer end 46 provides visual indication to the operator that the metal-to-metal seal at nose arrangement 60 is set. Once stem 42 is set against tubing hanger 64 , the stem is positively locked in place by the split lockout ring 106 to thereby prevent loss of sealing at the nose arrangement 60 . During the setting operation the split lockout ring 106 is held off stem 42 by hydraulic lockout piston 114 . The lockout piston 114 is depressurized once stem 42 is set. Wave spring 116 then forces the split lockout ring 106 to move forward and the toothed inner profile 108 of lockout ring then lockingly engages corresponding mating profile 112 formed on outer surface of stem 42 . Metal-to-metal seal 130 may also be effected between stem 42 and main housing assembly 134 when the stem is locked in place.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. These embodiments are not intended to limit the scope of the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims. | A well completion system includes a wellhead, a control line assembly for use in completions that is mounted to the wellhead, and a tubing hanger. The control line assembly includes a cylinder, a main housing assembly, a passage and a metal-to-metal seal. A split lockout ring provides a positive lock to the passage. Control lines enter the tubing hanger and exit via the wellhead. This arrangement on the wellhead provides sufficient height and clearance to allow for the installation of a plurality of control lines. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation-in-part of currently pending U.S. patent application Ser. No. 14/244,091, entitled “DOOR COLLAR LOCK”, filed Apr. 3, 2014, which is a continuation-in-part of abandoned U.S. patent application Ser. No. 14/099,912, entitled “DOOR COLLAR LOCK”, filed Dec. 7, 2013.
FIELD OF THE INVENTION
The present invention generally relates to a door collar lock. More specifically, the invention relates to a system and method for securing a door in a closed position using a door collar locking device.
BACKGROUND OF THE INVENTION
The use of door closing mechanisms having a rod and associated piston operating within a cylinder is well known. For instance, in residential applications, it is well known to connect such a mechanism between the door and its frame to act as a shock absorber or dampener against the action of a closing force such as a spring or a partial vacuum within the cylinder.
It has been known to provide different types of stops in conjunction with such closing mechanisms, which allow the door to be closed only partially, thereby temporarily maintaining the door in the desired position against the closing force. One of the more common types of prior art devices consists of a stop washer mounted on the piston rod. The washer is wedged between the rod and the cylinder to prevent the rod from being drawn in to the cylinder.
While different ways of temporarily keeping a door having a pneumatic piston and rod mechanism open have been contemplated and made available, few systems have focused on keeping a door with a pneumatic piston and rod closed for emergency purposes.
Recent tragic events such as those at Sandy Hook Elementary School in Connecticut, Columbine High School, and other locations, have prompted discussions on ways to improve security in schools and in other venues. In some instances, due to fire code regulations, and the like, the use of door locks may be disallowed. Still, even door locks may be vulnerable to forced entry because typical door locks are easily kicked-in or pushed open by blunt and sudden force.
Therefore, there is still a need for a system and method that overcomes the shortcomings of the above-mentioned prior art. The system and method described herein provides such a system and method by preventing opening of a door with a pneumatic piston and rod mechanism.
SUMMARY OF THE INVENTION
According to a preferred embodiment, an apparatus for holding a door closed, comprising: a top panel; a left wall; a right wall; a flap attached to the left wall opposite the top panel and folded under the apparatus; a flap attached to the right wall opposite the top panel and folded under the apparatus; a front end; a back end; and an opening at the front end that has a larger cross section than a cross section of the back end thereby providing for a tapered shape of the apparatus overall, such that the apparatus is configured to fit over two hinged arms of a door closing system, preventing the arms from articulating open to prevent the door from opening.
According to another preferred embodiment, a door collar lock, comprising: a top panel; a left wall; a right wall; a front end; a back end; a flap attached to the left wall opposite the top panel and folded under the apparatus; a flap attached to the right wall opposite the top panel and folded under the apparatus; and an opening at the front end that has a larger cross section than a cross section of the back end thereby providing for a tapered shape of the door collar lock overall, such that the door collar lock is configured to fit over two hinged arms of a door closing system, preventing the arms from articulating open to prevent the door from opening.
According to another preferred embodiment, a method for creating a customized apparatus for holding a door closed, comprising comparing a physical door hydraulic piston to two or more diagrammatic configurations to determine which of two or more computer aided design templates to use in fabrication; measuring a straight arm of the physical door hydraulic piston to produce a measurement M 1 ; measuring from the outside edge of the straight arm to an outside edge of an angled arm of the hydraulic piston to produce a measurement M 2 ; measuring a width of a pivot point of the hydraulic piston to produce a measurement M 3 ; measuring the collective height of the straight arm and the angled arm to produce a measurement M 4 ; selecting one of the templates from the two or more templates based on the comparing step; entering measurements M 1 , M 2 , M 3 and M 4 into the selected template to produce fabrication specifications; based on the fabrication specifications, fabricating a customized apparatus for holding a door closed, comprising: top panel; a left wall; a right wall; a flap attached to the left wall opposite the top panel and folded under the apparatus; a flap attached to the right wall opposite the top panel and folded under the apparatus; a front end; a back end; and an opening at the front end that has a larger cross section than a cross section of the back end thereby providing for a tapered shape of the apparatus overall, such that the apparatus is configured to fit over two hinged arms of a door closing system, preventing the arms from articulating open to prevent the door from opening.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a right front perspective view of a door collar lock according to one exemplary embodiment of the present invention;
FIG. 2 is a top elevational view of the embodiment of FIG. 1 ;
FIG. 3 is a left perspective view of a door with the door collar lock according to the embodiment of FIG. 1 .
FIG. 4 is a bottom right perspective view of a door with the door collar lock according to the embodiment of FIG. 1 .
FIG. 5 illustrates a door collar lock according to an alternative embodiment of the present invention.
FIG. 6 illustrates a door collar lock according to another alternative embodiment of the present invention.
FIG. 7 illustrates according to another alternative embodiment of the present invention.
FIG. 8 illustrates according to another alternative embodiment of the present invention.
FIG. 9 illustrates a door collar lock according to another alternative embodiment of the present invention.
FIG. 10 illustrates a door collar lock according to other alternative embodiment of the present invention.
FIG. 11 illustrates a door collar lock according to another alternative embodiment of the present invention.
FIG. 12 is a bottom, front perspective view of a door collar lock according to another alternative embodiment of the present invention.
FIG. 13 is a bottom left perspective view of the embodiment of FIG. 12 ; and
FIG. 14 is a left perspective view of a door having a door collar lock according to the embodiment of FIGS. 12 and 13 .
FIG. 15 is a full-front elevational view of typical door with a door collar lock according to the present invention.
FIG. 16 is a flow diagram that illustrates steps performed in a process to make a customized door collar lock according to the present invention.
FIG. 17 is a diagram illustrating two possible left mount hydraulic configurations.
FIG. 18 is a top elevational view of the hydraulic arm configuration shown in FIG. 17 .
FIG. 19 is another top elevational view of the hydraulic mount configuration in FIG. 17 .
FIG. 20 is another top elevational view of the hydraulic mount configuration in FIG. 17 .
FIG. 21 is a side view of the mount configuration of FIG. 17 .
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.
Various inventive features are described below that can each be used independently of one another or in combination with other features.
Broadly, embodiments of the present invention generally provide a door collar lock that can be easily installed over the rods of a pneumatic door mechanism to prevent entry. With reference to FIG. 1 , a right front perspective view of a door collar lock 10 is shown according to one embodiment. In one embodiment, the door collar lock 10 may comprise a front end 8 , a back end 9 , a left wall 4 (having an inner wall 2 ), and a right wall 3 (having an inner wall 1 ). The front end 8 may comprise an opening 5 , which may have a planar area that may be smaller than the cross section of the front end 9 , providing for a tapered shape of the door collar lock 10 overall.
The relative triangular shapes of a top panel 6 of the door collar lock 10 , and a bottom panel 7 illustrate the tapering from back to front of the door collar lock 10 , as also illustrated in the partial view of the inner wall 11 of the bottom panel 7 .
With reference to FIG. 2 , a top elevational view of the door collar lock 10 of FIG. 1 is shown. The tapered shape of the door collar lock 10 is illustrated in FIG. 2 , more specifically as illustrated by the shape of the top panel 6 .
With reference to FIG. 3 , a left perspective view of a door 30 with a pneumatic or spring actuated arm and rod configuration is shown, with the door collar lock 10 installed to prevent the door 30 from opening according to the embodiment of FIG. 1 . The rod or elbow 22 a and 22 b may consist of two articulating elongated members 22 a and 22 b over which the door collar 10 may be fitted by insertion over the elongated members 22 a and 22 b . Normally, the two elongated members 22 a and 22 b are free to articulate as allowed or caused by the pneumatic, hydraulic, or spring piston 20 . While the piston 20 may bias the elongated members 22 a and 22 b to push the door 30 into the closed position with respect to the door frame 32 , such a bias toward closing does not function as a lock. A person of average or low strength may still push the door open with little or no effort, as designed. However, in an emergency situation, it may be desirable to push the door collar lock 10 over the arms 22 a and 22 b.
With reference to FIG. 4 , a bottom right perspective view of the door collar lock 10 installed to prevent the rods 22 a and 22 b from scissoring outwardly to a more oblique angle α so as to prevent opening of the door 30 is shown. The rods 22 a and 22 b are shown in phantom for the portion covered by the door collar lock 10 , and the hinge 26 between the rods 22 a and 22 b is further illustrated in phantom. The door collar lock 10 functions to keep the rods 22 a and 22 b at a relatively more acute angle β rather than when the door 30 is in the open position with respect to the frame 32 . In one embodiment, the angle β comprises an angle by which the door 30 is substantially in a closed position with respect to the door frame 32 , so as to prevent entry by a potential wrong doer in an emergency. In one embodiment, the angle α comprises a wider angle than angle β, so as to prevent or deter a wrong doer from entry in an emergency.
As shown in FIG. 4 , the elongated design of the sides 3 and 4 of the door collar lock 10 functions to provide a distributed pressure along some or most of the length of the rods 22 a and 22 b when there is attempt to force the door 30 open. Having this elongated length and pressure along the rods 22 a and 22 b , as opposed to just one small portion of the rods 22 a and 22 b , makes for a more rigid stoppage of the door 30 from opening. The larger area of distribution of the pressure along the sides 3 and 4 , and the planar surface areas of the top ( 6 in FIGS. 1 and 2 ) and bottom 7 of the door collar lock 10 further provides more rigidity.
Put another way, the left wall 3 and the wall 4 are configured at an angle with respect to each other so as to contact a relative substantial part of side surface areas of the arms 22 a and 22 b for increased distribution of force placed by the arms on the apparatus 10 as opening force is placed on the door 30 . In this respect, the top 6 and bottom 7 comprise solid substantially triangular plates so as to further distribute the force placed on the apparatus 10 by the arms 22 a and 22 b as opening force is placed on the door 30 .
FIGS. 5-9 illustrate various embodiments that provide for various storage solutions for the door collar lock 10 . Storage at or in the general area of the door collar lock 10 may prevent, for example, a teacher in a classroom, or manager in an office, from having to search for the door collar lock 10 in an extreme panic during an emergency. For example, with specific reference to FIG. 5 , an alternative embodiment of the door collar lock 10 includes wheels 50 on small carriages configured to roll along a mount on the door frame 32 , on the side of one of the rods 22 a and 22 b , or on one of the rods 22 a itself. The door collar lock 10 can then be stored to the side of the rods 22 a and 22 b when not in use, but then rolled into position when the door 30 is closed, over both of the rods 22 a and 22 b , during an emergency when in use, as shown in position in FIG. 5 .
With reference to FIG. 6 , yet another alternative embodiment of the door collar lock 10 is shown with one or more magnets 60 attached to the top 6 as a mounting mechanism. In this embodiment, the door collar lock 10 may be magnetically attached to a steal structure, such as the door 30 or door frame 32 when not in use, but remain easily accessible during an emergency.
With reference to FIG. 7 , yet another alternative embodiment of the door collar lock 10 is shown with one or more wall mounting holes 70 located in the top 6 as a mounting mechanism. As with the magnets 60 in FIG. 6 , the wall mounting holes 70 allow the door collar lock 10 to be position mounted in proximity to the door 30 by means of one or more nails or mounting brackets in the door 30 or wall near the door.
With reference to FIG. 8 , yet another alternative embodiment of the door collar lock 10 is shown with a mounting hook 64 located in the top 6 as a mounting mechanism. The wall-mounting hook 64 allows the door collar lock 10 to be position mounted in proximity to the door 30 by means of a nail or mounting bracket in the door 30 or wall near the door.
With reference to FIG. 9 , yet another alternative embodiment of the door collar lock 10 is shown with a knob 66 to allow for more clearance for the hinge 26 within the device 10 when mounted on the elbows or arms 22 a and 22 b.
With reference to FIG. 10 , yet another alternative embodiment of the door collar lock 10 is shown with a bevel 70 that may allow the device 10 to be more easily tightened around smaller sized arms 22 a and 22 b.
With reference to FIG. 11 , yet another alternative embodiment of the door collar lock 10 is shown with an extension or insert 16 having a ridge configured to slide into the opening 5 of the device 10 to extend the length of the device 10 for adjustment for shorter or longer arms 22 a and 22 b . After the extension 16 is inserted into the opening 5 , the arms 22 a and 22 b are fit through the extension's opening 15 .
With reference to FIG. 12 , a bottom, front perspective view of an alternative embodiment of the door collar lock 10 is shown. The embodiment of FIG. 12 may comprise an embodiment that eliminates any need for welding of the door collar lock 10 . Instead of a having a solid bottom panel 7 as in the embodiments of FIGS. 1-11 , the embodiment of FIG. 12 has a portion of the bottom panel cut out, with instead, two flaps 50 that extend from the sides 3 and 4 of the lock 10 , bent into the bottom of the lock 10 .
With reference to FIG. 13 , a bottom left perspective view of the embodiment of FIG. 12 is shown. The top 9 of the door collar lock 10 may comprise an end cap 52 that is extended from the bottom panel 7 , and which may not be directly connected to the sides 3 and 4 of the lock 10 for ease of manufacturing, which may result in slits 60 down the sides of the end cap 54 between the sides 3 and 4 and the end cap 54 . Optionally, the end cap 54 may be attached, welded, or glued to the sides 3 and 4 after shaping of the lock 10 during manufacturing.
The embodiment of FIGS. 12 and 13 may allow the door collar lock 10 to be made by brake-pressing it. The whole pattern can be laid flat (from one geometric shape) and cut by a laser. Next, a brake machine may make five brakes to fold the finished brake press lock 10 . There may be, for example, one brake for the end cap 54 , and another brake for each side 3 and 4 , and another two breaks to fold the flaps 52 that form the open channel on the bottom. This embodiment may cut down significantly on costs of manufacturing, without compromising strength. In this respect, in one embodiment, it may be advantageous to use a gauge of steel of sufficient thickness for the rigidity to cause toe creases or brakes in the lock 10 to remain substantially permanent during use to hold when the lock 10 is put under duress.
With reference to FIG. 14 , a left perspective view of a door with a pneumatic or spring actuated arm and rod configuration, with the embodiment of FIGS. 12 and 13 installed to prevent the door from opening is shown. As shown in FIG. 14 , even in the absence of a solid bottom 7 as with the embodiment of FIG. 3 , the flaps 52 still provide enough force over the arms 22 a and 22 b to prevent a person from pushing the door open when the embodiment of FIG. 14 is installed over the arms 22 a and 22 b , functioning in the same way as the embodiment of FIG. 3 .
Method and System for Customization
With reference to FIG. 15 , a full-front elevational view of typical door with a hydraulic, or spring piston 20 to bias the elongated members (e.g. 22 b ). In a system and method for customization, a first step may be to locate the position of the hydraulic piston 20 where the door collar lock 10 may be installed, as indicated by the circle 95 .
In this regard, this first step may also be thought of as the first step to customizing a door collar lock 10 . With reference to FIG. 16 , a flow diagram illustrates steps performed in a process to make a customized door collar 10 according to one embodiment. In step 402 , a potential user (customer) of the door collar 10 may determine location or position of the hydraulic piston 20 (as illustrated in FIG. 15 by the circle 95 ).
In step 406 , the customer may compare their door and hydraulic piston configuration to a diagram of left and right pictorial configurations. With reference to FIG. 17 , two possible left mount hydraulic configurations are shown. For example, there may be an A configuration 200 of the left mount hydraulic arm, and a B configuration 202 , by which the user can view his or her hydraulic arm 20 and selected from the A configuration 200 and B configuration 202 .
Referencing back to FIG. 16 , in step 406 , the customer may then take a measurement of the straight arm 22 a that is substantially parallel to the door 30 (when the door is in the closed position). With reference to FIG. 18 , a top elevational view of the model A type hydraulic arm 20 is shown, with indications M 1 of where the customer should measure the straight arm 22 a that is substantially parallel to the door 30 . In step 406 , the measurement M 1 is the length of the straight arm 22 a , starting at the outside edge of the pivot point or hinge 26 to a half inch to one inch before the first obstruction (bend or closer box).
In step 408 , the customer may perform an open sleeve measurement. With reference to FIG. 19 , another top elevational view for the hydraulic arm of FIG. 18 showing where the customer should measure a length of the open sleeve M 2 . The measurement M 2 is for the opening of the door collar 10 . The customer may measure from the outside edge of the straight arm 22 a to the outside edge of the angled arm 22 b . In one embodiment, for the most accurate measurement, the customer may make the tape measure or ruler completely perpendicular to the door 30 to provide a snug fit for the door collar 10 .
With reference back to FIG. 16 , in step 410 , the user may measure the width of the pivot point or hinge 26 . With reference to FIG. 20 , another top elevational view for the hydraulic arm 20 of FIG. 18 showing where the customer should measure a length of the pivot or hinge 26 is shown. The customer may measure the length as shown by M 3 of FIG. 20 .
With reference back to FIG. 16 , in step 412 , the user may take the measurement of the thickness or collective height of the two closer arms 22 a and 22 b at a thickest point (usually at the hinge). With reference to FIG. 21 , front elevational view for the hydraulic arm 20 of FIG. 18 showing where the customer should measure the two closer arms 22 a and 22 b is shown. This measurement M 4 may be from the highest and lowest points of the closer arms 22 a and 22 b . If a nut or knob 180 adds thickness to the arms 22 a and 22 b , then the measurement M 4 may include this thickness.
In step 414 , the customer may transmit the measurements to the manufacturer. Transmission may be through electronic means, or by filling out an HTML form on the internet.
In step 416 , the manufacturer may take the received measurements, M 1 , M 2 , M 3 , and M 4 , and plug them into a CAD template. CAD templates are widely available as known by those of skill in the art. They allow manufacturers to create a template of a device, and devise different sizes by defining measurements of certain parts of the template in the CAD system. The CAD system can then proportionally and automatically re-size the CAD object, and produce fabrication specifications for the fabrication machine or fabricator, which may using, by way of example, and not by way of limitation, lazar cutting of metal to produce the object. Such CAD systems that allow this type of templating are available from many sources, including PTC Creo by PTC, Inc. of Needham, Mass. 02494, USA.
With reference to FIG. 20 , a CAD template 300 that may be used for customization of the door collar lock 20 is shown. A template table 350 may provide an entry interface for entering the received measurements M 1 , M 2 , M 3 , and M 4 . The template may then adjust the proportional sizes of the object in the template to produce a manufacturing fabrication file, for example, in the form of a drawing interchange format or drawing exchange format (DXF) that can be used by the fabrication machinery to produce the door collar lock 20 .
It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims. | A method for creating a customized apparatus for holding a door closed comprises comparing a physical door hydraulic piston to two or more diagrammatic configurations to determine which of two or more computer aided design templates to use in fabrication. A straight arm of the physical door hydraulic piston is measured to produce a measurement M 1 . A user measures from the outside edge of the straight arm to an outside edge of an angled arm of the hydraulic piston to produce a measurement M 2 . A user measures a width of a pivot point of the hydraulic piston to produce a measurement M 3 . A user measures the collective height of the straight arm and the angled arm to produce a measurement M 4 . A user selects one of the templates from the two or more templates based on the comparing step. A CAD operator enters measurements M 1 , M 2 , M 3 and M 4 into the selected template to produce fabrication specifications. Based on the fabrication specifications, a customized apparatus is fabricated for holding a door closed. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 12/532,365, filed Sep. 21, 2009 (now U.S. Pat. No. 8,906,865), which is the U.S. national stage of PCT/GB2008/001020, filed Mar. 25, 2008, which claims priority to and benefit of Great Britain Patent Application No. 0705488.5, filed Mar. 22, 2007, the contents of each of which are herein incorporated by reference for all purposes.
INCORPORATION-BY-REFERENCE OF MATERIAL
Electronically Filed
[0002] Incorporated by reference in its entirety herein is a computer-readable nucleotide/amino acid sequence listing submitted concurrently herewith and identified as follows: One 15,734 kilobyte ASCII (text) file named “Seq_list” created on Dec. 5, 2014.
FIELD OF THE INVENTION
[0003] This invention relates to the treatment of inflammation and/or endotoxic shock and/or to the reduction of levels of inflammatory chemokines, and to compositions for use in the treatment of inflammation and/or endotoxic shock, or for the reduction of levels of inflammatory mediators.
BACKGROUND
[0004] Inflammation is a component of the pathogenesis of many human and animal diseases, as well as arising as a result of physical, chemical or traumatic damage to tissues in a human or animal body. In general, the immune response results in the systemic release of endogenous chemical mediators which cause vasodilation, migration of neutrophils, chemotaxis, and increased vascular permeability. The immune response is essentially the same wherever it occurs and whatever the cause. The response can be acute (short lived) or it may be chronic (long lasting).
[0005] Endotoxic shock, sometimes also referred to as septic shock, is thought to occur due to intravascular exposure to large amounts of endotoxin resulting in an inflammation like response. Exposure to endotoxin results in the production of a number of cytokines, including TNFα and IL-1. The complement system and the coagulation cascade, including Factor VII are also stimulated. The result of this reaction can be tissue damage, fever, vasodilation, tachycardia and intravascular coagulation.
[0006] An inflammatory response is typically beneficial, giving the site of inflammation increased access to nutrients, oxygen, antibodies and therapeutic drugs, as well as increased fibrin formation and dilution of toxins. However, if inflammation is unwanted or prolonged then it can cause damage to the tissue. In such situations, anti-inflammatory drugs are often used. There are two main types of anti-inflammatory drugs, corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs). Most of these drugs have unwanted side effects. Prolonged corticosteroid administration is frequently associated with serious side effects that mimic Cushing's disease, a malfunction of the adrenal glands resulting in overproduction of cortisol. Other potential side effects include weight gain, fat deposits in the chest, face, neck and upper back, oedema, hypertension, diabetes, poor wound healing, increased susceptibility to infection, thinning of the skin, mood swings and depression. The most serious side effects of NSAIDS are kidney failure, liver failure, ulcers and prolonged bleeding after an injury or surgery. Some individuals are allergic to NSAIDs and people with asthma are at a higher risk for experiencing a serious allergic reaction to aspirin. There is therefore a need to identify alternative agents which have anti-inflammatory effects.
[0007] Chemerin is an abundant protein present in a range of human inflammatory exudates including ascitic and synovial fluid (Wittamer V et al. J Exp Med. Oct. 6 2003; 198(7):977-985; Meder Wet et al. FEBS Lett. Dec. 18 2003; 555(3):495-499). Human Chemerin is secreted as a 163 amino acid (aa) precursor referred to as ProChemerin (the Mus musculus , murine equivalent is 162aa) which undergoes N- and C-terminal truncation to generate a 137aa chemotactic protein (140aa in Mus musculus ) (Wittamer V et al. J Exp Med. Oct. 6 2003; 198(7):977-985; Zabel B A et al. J Biol Chem. Oct. 14 2005; 280(41):34661-34666; Wittamer V et al. J Immunol. Jul. 1 2005; 175(1):487-493; Samson M et al. Eur J Immunol. May 1998; 28(5):1689-1700). The predicted structure for Chemerin indicates structural similarities to chemokines and it has been described as a “reverse” chemokine, potentially possessing a disordered carboxyl-terminus, an α-pleated sheet and a β-helical amino-terminal domain (Zabel B A et al. Exp Hematol. August 2006; 34(8):1021-1032). The structure is reminiscent of the cystatin fold present in cathelicidins and kininogens which also undergo proteolytic processing to achieve activation (Zabel B A et al. Exp Hematol. August 2006; 34(8):1106-1114; Colman R W, Biol Chem. January 2001; 382(1):65-70; Yamasaki K et al. FASEB J. Oct. 1, 2006 2006; 20(12):2068-2080).
SUMMARY
[0008] According to a first aspect, the present invention provides the use of one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof, in the preparation of a medicament for the treatment of inflammation.
[0009] According to another aspect, the invention provides the use of one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof, in the preparation of a medicament for the treatment of endotoxic shock.
[0010] According to a further aspect, the invention provides the use of one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof, in the preparation of a medicament for reducing the level of one or more inflammatory mediators.
[0011] According to a yet further aspect, the present invention provides one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof, for use in the treatment of inflammation, and/or in the treatment of endotoxic shock, and/or to reduce the level of one or more inflammatory mediators.
[0012] The one or more inflammatory mediators may include cytokines, chemokines and lipids that mediate inflammation. The inflammatory mediator may include one or more chemokines selected from the group comprising TNFα, IL-1α, IL-1β, IL-6, IL-12, G-CSF, MCP-2 (CCL8), GROα ((CXCL1), GROβ (CXCL2), IL-8 (CXCL8), TECK (CCL25), MCP-1 (CCL2), interferon γ and RANTES (CCL5). Preferably, the medicament can reduce levels of TNFα.
[0013] Surprisingly, peptides derived from the C-terminal end of the Chemerin protein have anti-inflammatory properties, and may be used to treat, prevent or ameliorate inflammation and/or endotoxic shock.
[0014] The medicament may have a therapeutic and/or a prophylactic use.
[0015] Preferably, the peptide is between about 5 and about 30 amino acids. More preferably, the peptide is between about 5 and about 25 amino acids, preferably, the peptide is between about 5 and about 20 amino acids.
[0016] Preferably the peptide comprises between about 5 and about 30 amino acids derived from the C-terminal end of a Chemerin protein, or an analog or a derivative thereof. More preferably, the peptide is between about 5 and about 25 amino acids, preferably, the peptide is between about 5 and about 20 amino acids.
[0017] Reference to a Chemerin protein means the processed form of Chemerin, in which the N-terminal amino acids found in the PreProChemerin have been proteolytically removed, and the C-terminal amino acids found in ProChemerin precursor have been proteolytically removed to produce the active truncated form of the protein referred to as Chemerin.
[0018] Preferably the peptide is derived from a human or non-human form of Chemerin. Preferably the peptide is derived from a human or mammalian form of Chemerin. The mammalian non-human Chemerin may be derived from a rodent, such as a rat or a mouse, a horse, a dog, a cat, a cow, a sheep or a pig.
[0019] Preferably the peptide derived from the C-terminal end of a Chemerin protein has at least 30% or higher identity with the naturally occurring C-terminal end of the Chemerin protein. Preferably the peptide has at least 40%, 50%, 60%, 70%, 80%, 90% or higher identity with the naturally occurring peptide sequence at the C-terminal end of the Chemerin protein.
[0020] Preferably the peptide has at least 30% or higher sequence identity with between about the last 5 and about the last 30, preferably between about the last 10 and about the last 25, amino acids which naturally occur at the C-terminal end of a Chemerin protein. Preferably the peptide has at least about 40%, 50%, 60%, 70%, 80%, 90% or higher sequence identity with between about the last 5 and about the last 30, preferably between about the last 10 and about the last 25, amino acids which naturally occur at the C-terminal end of a Chemerin protein.
[0021] Preferably the peptide has at least 30% or higher sequence identity with between 5 and 25 amino acids in the last 30 amino acids which naturally occur at the C-terminal end of a Chemerin protein. Preferably the peptide has at least about 40%, 50%, 60%, 70%, 80%, 90% or higher sequence identity with between 5 and 25 amino acids in the last 30 amino acids which naturally occur at the C-terminal end of a Chemerin protein.
[0022] Reference to the “last amino acids” in the Chemerin protein refers to the amino acids at the C-terminal end of the protein.
[0023] The full-length sequence of human and murine Chemerin, ProChemerin and PreProChemerin is given in FIG. 2A , and reflected in Seq ID nos: 31, 32, 33, respectively for the human proteins, and Seq ID nos: 34, 35, 36, respectively for the mouse proteins. Preferably the Chemerin peptide has the sequence of Seq ID No: 31 or 34. The sequence of Chemerin proteins from other species, such as bovine and rat, are readily available from GenBank and can be easily accessed by those skilled in the art.
[0024] Preferably the peptide has at least 30% or higher, more preferably 40%, 50%, 60%, 70%, 80%, 90% or higher sequence identity with between the last 5 and the last 30 amino acids of the Chemerin according to Seq ID no: 31 (human sequence) and Seq ID no: 34 (mouse sequence).
[0025] Percentage amino acid sequence identity is defined as the percentage of amino acid residues in a sequence that is identical with the amino acids in the naturally occurring Chemerin protein after aligning the sequences and introducing gaps if necessary to achieve the maximum percent sequence identity. Alignment for purpose of determining percent sequence identify can be achieved in many ways that are well known to the man skilled in the art, and include, for example, using BLAST and ALIGN algorithms.
[0026] The peptide may contain additions, insertions, deletions, inversions or translocations relative to the natural sequence of the C-terminal end of a Chemerin protein, provided that the peptide has at least 50% of the anti-inflammatory activity of, and/or at least 50% of the anti-endotoxic shock activity of, and/or the ability to reduce the level of one or more inflammatory mediators by at least 50% compared to, a peptide having the natural sequence.
[0027] The terms “analog” or “derivative” refers to peptides which have a sequence different to the naturally occurring sequence but which comprises essentially the same or more, and at least about 50%, preferably about 60%, 70%, 80% or 90%, of the anti-inflammatory activity, and/or the anti-endotoxic shock activity, inflammatory mediator reducing activity, observed with a peptide having a naturally occurring sequence.
[0028] A peptide analog or derivative may have one or more deletion, insertion, or modification of any amino acid residue, including the N or C-terminal residue. The peptide may be acetylated, acylated, alkylated, glycosylated, and the like. The peptide may also comprise additional amino acids either at the C or N terminal end, or at both ends.
[0029] The peptide, analog or derivative may be part of a fusion protein.
[0030] The peptide may include one or more conservative amino acid substitutions as compared with the naturally occurring amino acid sequence.
[0031] Preferably one or more of the peptides comprises a sequence selected from the group comprising:
[0000] (Chemerin11-mouse; C11m; Seq ID No: 1) PHGYFLPGQFA; (Chemerin12-mouse; C12m; Seq ID No: 2) PHGYFLPGQFAF; (Chemerin13-mouse; C13m; Seq ID No: 3) PHGYFLPGQFAFS; (Chemerin15-mouse; C15m; Seq ID No: 4) AGEDPHGYFLPGQFA; (Chemerin16-mouse; C16m; Seq ID No: 5) AGEDPHGYFLPGQFAF; (Chemerin17-mouse; C17m; Seq ID No: 6) AGEDPHGYFLPGQFAFS; (Chemerin12A-mouse; C12Am; Seq ID No: 7) DPHGYFLPGQFA; (Chemerin13A-mouse; C13Am; Seq ID No: 8) EDPHGYFLPGQFA; (Chemerin14A-mouse; C14Am; Seq ID No: 9) GEDPHGYFLPGQFA; (Chemerin13B-mouse; C13Bm; Seq ID No: 10) DPHGYFLPGQFAF; (Chemerin14B-mouse; C14Bm; Seq ID No: 11) EDPHGYFLPGQFAF; (Chemerin15A-mouse; C15Am; Seq ID No: 12) GEDPHGYFLPGQFAF; (Chemerin14C-mouse; C14Cm; Seq ID No: 13) DPHGYFLPGQFAFS; (Chemerin15B-mouse; C15Bm; Seq ID No: 14) EDPHGYFLPGQFAFS; (Chemerin16A-mouse; C16Am; Seq ID No: 15) GEDPHGYFPGQFAFS; (Chemerin11-human; C11h; Seq ID No: 16) PHSFYFPGQFA; (Chemerin12-human; C12h; Seq ID No: 17) PHSFYFPGQFAF; (Chemerin13-human; C13h; Seq ID No: 18) PHSFYFPGQFAFS; (Chemerin15-human; C15h; Seq ID No: 19) AGEDPHSFYFPGQFA; (Chemerin16-human; C16h; Seq ID No: 20) AGEDPHSFYFPGQFAF; (Chemerin17-human; C17h; Seq ID No: 21) AGEDPHSFYFPGQFAFS; (Chemerin12A-human; C12Ah; Seq ID No: 22) DPHSFYFPGQFA; (Chemerin13A-human; C13Ah; Seq ID No: 23) EDPHSFYFPGQFA; (Chemerin14A-human; C14Ah; Seq ID No: 24) GEDPHSFYFPGQFA; (Chemerin13B-human; C13Bh; Seq ID No: 25) DPHSFYFPGQFAF; (Chemerin14B-human; C14Bh; Seq ID No: 26) EDPHSFYFPGQFAF; (Chemerin15A-human; C15Ah; Seq ID No: 27) GEDPHSFYFPGQFAF; (Chemerin14C-human; C14Ch; Seq ID No: 28) DPHSFYFPGQFAFS; (Chemerin15B-human; C15Bh; Seq ID No: 29) EDPHSFYFPGQFAFS; and (Chemerin16A-human; C16Ah; Seq ID No: 30) GEDPHSFYFPGQFAFS;
or analogs or derivatives thereof.
[0032] Preferably one or more of the peptides comprises a sequence selected from the group comprising:
[0000] AQAGEDPHGYFLPGQFAFS (Chemerin19-mouse; C19m; Seq ID No: 37);
and
QRAGEDPHSFYFPGQFAFS (Chemerin19-human; C19h; Seq ID No: 38);
or analogs or derivatives thereof.
[0033] Preferably the peptide has at least 30%, 40%, 50%, 60%, 70%, 80%, 90% or higher sequence identity with one or more of the peptides referred to above as Seq ID No: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30.
[0034] Preferably the peptide has at least 30%, 40%, 50%, 60%, 70%, 80%, 90% or higher sequence identity with one or more of the peptides referred to above as Seq ID No: 37 or 38.
[0035] Preferably an analog or derivative of a peptide derived from the C-terminal end of a Chemerin protein includes small molecule mimetics of a peptide.
[0036] The peptide, analog or derivative, may be isolated from a natural system, or it may be synthetically or recombinantly produced. Synthesised peptides may be produced by standard chemical methods, including synthesis by automated procedure.
[0037] Recombinant peptides may be used in a purified form. Alternatively, the supernatant from cells expressing the recombinant peptide may be used.
[0038] The peptide, analog or derivative may form part of a larger protein or molecular complex.
[0039] The peptide may be a straight chain or cyclic.
[0040] The peptide may include a protease resistant backbone.
[0041] The peptide may include modifications at the C and/or N terminus.
[0042] The peptide may be labelled, such as with a radioactive label, fluorescent label, a mass spectrometry tag, biotin or the like, by methods known in the art.
[0043] The medicament may comprise other active ingredients, including other known anti-inflammatory agents, and/or other known anti-endotoxic shock agents, and/or other agents known to reduce chemokines levels.
[0044] The medicament may also contain a pharmaceutically acceptable excipient. The excipient may comprise large macromolecules such as proteins, polysaccharides, polylactic acids, polyglycolic acids, polymeric amino acids, amino acid copolymers, trehalose, lipid aggregates and inactive virus particles. Such excipients will be well known to those skilled in the art.
[0045] The medicament may also comprise one or more of a buffering agent, a viscosity-increasing agent, a solvent, a stabiliser and a preservative.
[0046] The route of administration of the medicament may be injection or infusion by parenteral, subcutaneous, intravenous, intramuscular, intraperitoneal, intraarterial, intralesional, intrarticular, topical, oral, rectal, nasal, inhalation or any other suitable route.
[0047] The dosage of the peptides used will depend on the peptide, the target and the treatment. The determination of the dosage and route of administration is well within the skill of an ordinary physician. Normal dosage regimes may vary from about 1 pg/kg to about 100 mg/kg, more preferably the dosage will be from about 10 pg/kg to about 1 mg/kg, more preferably from about 10 pg/kg to about 100 ng/kg. Preferably these dosages are doses per day.
[0048] Surprisingly it has been found that a dose as low as 0.32 ng/kg of a peptide according to the invention has efficacy against sterile peritonitis in mice, whereas 1.2 mg/kg of dexamethasone is required to observe a similar degree of efficacy.
[0049] Preferably a medicament according to a use of the invention may be intended for administration at a dose of between about 10 pg/kg and about 1 mg/kg, more preferably at a dose of between about 10 pg/kg and about 100 ng/kg, or between about 10 pg/kg and about 10 ng/kg. These doses are at least three logs lower than the dose of dexamethasone needed.
[0050] According to another aspect the invention provides a method of treating, preventing or ameliorating inflammation in a subject comprising administering to the subject one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof.
[0051] According to another aspect the invention provides a method of treating, preventing or ameliorating endotoxic shock in a subject comprising administering to the subject one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof.
[0052] According to another aspect the invention provides a method of reducing the level of one or more inflammatory mediators in a subject comprising administering to the subject one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof.
[0053] The treatment may be therapeutic, prophylactic or cosmetic.
[0054] Preferably the peptide is administered in an effective amount, that is, in an amount sufficient to: (i) induce or cause a reduction in inflammation, or which prevents or reduces inflammation; (ii) induce or cause a reduction in endotoxic shock, or which prevents or reduces endotoxic shock; and/or (iii) reduce the level of one or more inflammatory mediators.
[0055] Alternatively the medicament of the invention may be applied directly to a medical device to reduce the risk of device related inflammation. This may be achieved by applying the medicament to the surface of the device or by impregnating the surface of the device with one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof.
[0056] According to another aspect, the invention provides a medical device impregnated with one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof.
[0057] The medical device may be a stent or a catheter.
[0058] According to another aspect, the invention provides a wound dressing or bandage impregnated with one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof.
[0059] The inflammation referred to in any aspect of the invention may be associated with a condition such as juvenile chronic arthritis, spondyloarthropathies, systemic sclerosis (scleroderma), idiopathic inflammatory myopathies (dermatomyositis, polymyositis), Sjogren's syndrome, systemic vasculitis, sarcoidosis, autoimmune hemolytic anemia (immune pancytopenia, paroxysmal nocturnal hemoglobinuria), autoimmune thrombocytopenia (idiopathic thrombocytopenic purpura, immunemediated thrombocytopenia), thyroiditis (Grave's disease, Hashimoto's thyroiditis, juvenile lymphocytic thyroiditis, atrophic thyroiditis), autoimmune inflammatory diseases (e.g., allergic encephalomyelitis, multiple sclerosis, insulin-dependent diabetes mellitus, autoimmune uveoretinitis, thyrotoxicosis, scleroderma, systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease (e. g., Crohn's disease, ulcerative colitis, regional enteritis, distal ileitis, granulomatous enteritis, regional ileitis, terminal ileitis), autoimmune thyroid disease, pernicious anemia, allograft rejection, diabetes mellitus, immune-mediated renal disease (glomerulonephritis, tubulointerstitial nephritis), demyelinating diseases of the central and peripheral nervous systems such as multiple sclerosis, idiopathic demyelinating polyneuropathy or Guillain-Barre syndrome, and chronic inflammatory demyelinating polyneuropathy, hepatobiliary diseases such as infectious hepatitis (hepatitis A, B, C, D, E and other non-hepatotropic viruses), autoimmune chronic active hepatitis, primary biliary cirrhosis, granulomatous hepatitis, sclerosing cholangitis, gluten-sensitive enteropathy, Whipple's disease, autoimmune or immune-mediated skin diseases including bullous skin diseases, erythema multiforme and contact dermatitis, psoriasis, allergic diseases such as asthma, allergic rhinitis, atopic dermatitis, food hypersensitivity and urticaria, immunologic diseases of the lung such as eosinophilic pneumonias, idiopathic pulmonary fibrosis and hypersensitivity pneumonitis, transplantation associated diseases including graft rejection and graftversus-host-disease, infectious diseases including viral diseases such as AIDS(HIV infection), herpes, etc., bacterial infections, fungal infections, protozoal infections, parasitic infections, and respiratory syncytial virus, human immunodeficiency virus, etc., eczema and endotoxic shock.
[0060] According to a further aspect the invention provides a peptide capable of treating, preventing or ameliorating inflammation selected from the group comprising peptides with the sequence of Seq ID No: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 and analogs or derivatives thereof.
[0061] According to a further aspect the invention provides a peptide capable of treating, preventing or ameliorating inflammation selected from the group comprising peptides with the sequence of Seq ID No: 37, 38 and analogs or derivatives thereof.
[0062] According to a further aspect the invention provides a peptide capable of treating, preventing or ameliorating endotoxic shock selected from the group comprising peptides with the sequence of Seq ID No: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 and analogs or derivatives thereof.
[0063] According to a further aspect the invention provides a peptide capable of treating, preventing or ameliorating endotoxic shock selected from the group comprising peptides with the sequence of Seq ID No: 37, 38 and analogs or derivatives thereof.
[0064] According to a further aspect the invention provides a peptide capable of reducing the level of one or more inflammatory mediators selected from the group comprising peptides with the sequence of Seq ID No: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 and analogs or derivatives thereof.
[0065] According to a further aspect the invention provides a peptide capable of reducing the level of one or more inflammatory mediators selected from the group comprising peptides with the sequence of Seq ID No: 37, 38 and analogs or derivatives thereof.
[0066] According to another aspect the invention provides a pharmaceutical composition comprising one or more peptides selected from the group comprising peptides with the sequence of Seq ID No: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 and 30 and analogs or derivatives thereof.
[0067] According to another aspect the invention provides a pharmaceutical composition comprising one or more peptides selected from the group comprising peptides with the sequence of Seq ID No: 37 and 38 and analogs or derivatives thereof.
[0068] The pharmaceutical composition may be for the treatment and/or prevention of inflammation, and/or the treatment and/or prevention of endotoxic shock, and/or for the reduction of the level of one or more inflammatory mediators, such as cytokines and chemokines.
[0069] According to a further aspect the invention provides a peptide having the sequence of Seq ID No: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30 or an analog or derivative thereof.
[0070] According to a further aspect the invention provides a peptide having the sequence of Seq ID No: 37 or 38 or an analog or derivative thereof.
[0071] According to a further aspect the invention provides a peptide having at least 50% sequence identity to a peptide having the sequence of Seq ID No: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30. Preferably the peptide has at least 60%, 70%, 80%, 90% or 95% sequence identity to a peptide having the sequence of Seq ID No: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30.
[0072] According to a further aspect the invention provides a peptide having at least 50% sequence identity to a peptide having the sequence of Seq ID No: 37 or 38. Preferably the peptide has at least 60%, 70%, 80%, 90% or 95% sequence identity to a peptide having the sequence of Seq ID No: 37 or 38. According to a further aspect the invention provides use of one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof, in the preparation of a medicament for the treatment of a wound.
[0073] According to a further aspect the invention provides a method of treating, preventing or ameliorating a wound in a subject comprising administering to the subject one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof.
[0074] According to a further aspect the invention provides a pharmaceutical composition comprising one or more peptides selected from the group comprising peptides with the sequence of Seq ID No: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 37 or 38 or an analog or derivative thereof for the treatment of a wound.
[0075] According to a further aspect the invention provides one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof, for use in the treatment and/or prevention of inflammation, and/or the treatment and/or prevention of endotoxic shock, and/or for the reduction of the level of one or more inflammatory mediators, such as cytokines and chemokines.
[0076] According to a further aspect the invention provides one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof, for use in the treatment of a wound.
[0077] The skilled man will appreciate that any of the preferable features discussed above can be applied to any of the aspects of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0078] Preferred embodiments of the present invention will now be described, merely by way of example, with reference to the following figures and examples.
[0079] FIGS. 1A and 1B illustrate that Chemerin140 suppresses production of inflammatory mediators by macrophages in a proteolysis dependent fashion. Supernatants from macrophages or activated macrophages (treated with 100 ng/ml LPS and 20 ng/ml interferon gamma were assayed for cytokine expression using Luminex and ELISA assays. Cells were incubated in the presence or absence of recombinant murine chemerin or dexamethasone at the indicated doses and in the absence or presence of the protease inhibitor leupeptin (15 mg/ml).
[0080] FIG. 1C shows Macrophage cytokine mRNA levels were quantitated by qRT-PCR (IL-10, TGFβ) and normalized to HPRT.
[0081] FIG. 1D shows PMΦ were pre-treated with chemerin (0.1-1 pM)±pertussis toxin (PTX; 200 ng/ml) prior to LPS/IFNγ-challenge.
[0082] FIG. 1E shows PMΦ were pre-treated with chemerin (1 pM) for 1 h±PTX and then stimulated with LPS/IFNγ for 4 h, 8 h or 15 h. ***, p<0.001; **, p<0.01; *, p<0.05 relative to LPS/IFNγ-treated samples. ###, p<0.001; ##, p<0.01; #, p<0.05 relative to chemerin-treated samples.
[0083] FIG. 1F shows peritoneal macrophages (PMD) were pre-treated with chemerin (1 pM), chemerin (1 pM)+protease inhibitor (Leupeptin [Leu], E-64, Pefabloc [Pef], Pepstatin A [Pep A], Calpeptin [Cal], Cathepsin S inhibitor [Cath S], Cathepsin L inhibitor [Cath L]) for 1 h and then stimulated with LPS (100 ng/ml) and IFNγ (20 ng/ml) for 15 h. Graphs show mean values±SEM from 3-8 independent experiments. nd; below limit of detection for this assay. ns, not significant;
[0084] FIG. 2A shows the amino acid sequence alignment of Human (upper sequence) and Mouse (lower sequence) Chemerin (Tig2). Amino acid sequences for Human (Protein Data Bank accession no. NP — 002880) and Murine (NP — 082128) Chemerin were aligned and analysed using PeptideCutter to generate predicted trypsin cleavage sites (black vertical lines). The full length sequence in bold and grey is the sequence of PreProChemerin (Seq ID No: 33 for human and Seq ID No: 36 for mouse). The sequence with the N terminal amino acids in grey removed is the ProChemerin sequence (Seq ID No: 32 for human and Seq ID No: 35 for mouse). The sequence in bold, with the N terminal and C-terminal amino acids in grey removed is the sequence of Chemerin (Seq ID No: 31 for human and Seq ID No: 34 for mouse).
[0085] Sequences for C-terminal peptides C11m (Seq ID No: 1), C13m (Seq ID No: 2), C15m (Seq ID No: 3) and C17m (Seq ID No: 4) are also given;
[0086] FIG. 2B illustrates that peptides derived from the C-terminal portion of Chemerin suppress pro-inflammatory mediator production by activated macrophages. Reference in this figure to the peptides C13, C15 and C17 refers to the peptides described previously as C13m, C15m and C17m, respectively;
[0087] FIG. 3 illustrates that Chemerin peptides exhibit little macrophage chemotactic properties in comparison to Chemerin140. Reference in this figure to the peptides C11, C13, C15 and C17 refers to the peptides described previously as C11m, C13m, C15m and C17m, respectively;
[0088] FIGS. 4A-H show chemotaxis mediated by chemerin, chemerin peptides and chemerin-treated supernatants. PMΦ (0.4×10 6 ) with or without 30 min Pertussis toxin pre-treatment (PTX; 200 ng/ml) were allowed to migrate towards chemoattractant in the bottom well of a modified Boyden chamber over 4 h.
[0089] FIG. 4A shows chemotaxis mediated by rmChemerin.
[0090] FIG. 4B shows chemotaxis mediated by chemerin peptide C15.
[0091] FIG. 4C shows chemotaxis mediated by chemerin peptide C11.
[0092] FIG. 4D shows chemotaxis mediated by chemerin peptide C13.
[0093] FIG. 4E shows chemotaxis mediated by chemerin peptide C19.
[0094] FIG. 4F shows chemotaxis mediated by chemerin peptide C6.
[0095] FIG. 4G shows chemotaxis mediated by chemerin peptide C8.
[0096] FIG. 4H shows PMΦ (7.5×10 5 ) were allowed to migrate towards conditioned media from untreated macrophages and macrophages treated with LPS/IFNγ±Chemerin or C15 in the bottom well of a modified Boyden chamber over 4 h. Graphs indicate mean Migration Index±SEM for each treatment group (n=4 independent experiments). ***, P<0.001; **, P<0.01; *, P<0.05 relative to PMΦ+PTX (student's t-test). Reference in this figure to the peptides C11, C13, C15 and C19 refers to the peptides described previously as C11m, C13m, C15m and C19m, respectively;
[0097] FIG. 5 illustrates that macrophages exhibit reduced chemotaxis towards conditioned media from Chemerin-treated macrophages. Reference in this figure to the peptides C15 and C17 refers to the peptides described previously as C15m and C17m, respectively;
[0098] FIG. 6 illustrates that Chemerin15-mouse suppresses Zymosan-induced peritonitis. Reference in this figure to the peptide C15 refers to the peptide described previously as C15m. Z refers to Zymosan;
[0099] FIGS. 7A-G show that chemerin15 ameliorates zymosan-induced peritonitis in mice.
[0100] FIGS. 7A and 7B show C57B16/J mice were dosed i.p with PBS or chemerin15 (0.32 ng/kg) followed by injection with PBS or zymosan (10 μg, ˜2×10 6 particles per cavity) 1 h later. Peritoneal exudate cells were harvested by peritoneal lavage at multiple time points ( FIGS. 7A and 7B ; 5-6 mice/treatment) or after 4 h ( FIGS. 7C-7E ; 6-15 mice/group).
[0101] FIGS. 7C-7D show total cell numbers in lavage fluid were quantified and cellular composition (neutrophils vs mononuclear phagocytes) determined using FACS analysis. Cells were blocked with 2.4G2 anti-FcγRII/III and stained with Ly-6G-PE and 7/4-FITC. Gates were constructed around two populations, the neutrophils (N; 7/4high, Ly-6Ghigh) and inflammatory monocytes (Mo; 7/4high, Ly-6Glow).
[0102] FIG. 7E shows representative FACS plots are shown for each treatment group at 4 h post-zymosan.
[0103] FIG. 7F shows peritoneal lavage fluid was assayed for TNFα and KC by ELISA and IL-6, IL-1β and MCP-1 by Luminex assay. C15; Chemerin15, Z; Zymosan. ***, P<0.001; **, P<0.01 ** relative to zymosan-treated animals (Student's t test).
[0104] FIG. 7G shows Mice (6-8/treatment) were dosed i.p with zymosan (10 μg) and with C15 (8 pg) or PBS either 1 h beforehand (C15 pre-treatment) or 2 h later (C15 post-treatment). Peritoneal lavage was carried out 4 h post-zymosan challenge. Reference in this figure to the peptide C15 refers to the peptide described previously as C15m;
[0105] FIGS. 8A-D show that anti-chemerin antibody neutralizes chemerin species and exacerbates peritoneal inflammation.
[0106] FIG. 8A shows PMΦ were used in macrophage chemotaxis assays (performed as detailed in FIG. 7 ) and allowed to migrate toward RANTES, chemerin or C15 with or without anti-rmChemerin antibody or control IgG. Graphs indicate mean Migration Index±SEM for each treatment group (n=4 independent experiments). ***, P<0.001; **, P<0.01; *, P<0.05 relative to chemoattractant.
[0107] FIG. 8B shows PMΦ were pretreated with 1 pM C15 or 1 pM chemerin with or without anti-rmChemerin antibody or control IgG for 1 h and then stimulated with LPS (100 ng/ml) and IFN′ (20 ng/ml) for 15 h. Mean expression of RANTES±SEM in macrophage supernatants after 16h was determined by ELISA (n=4 independent experiments). **, P<0.01; *, P<0.05 relative to LPS/IFNγ-treated samples.
[0108] FIGS. 8C and 8D show C57B16/J mice were dosed i.p with PBS, anti-rmChemerin antibody (100 ng/mouse) or control IgG (100 ng/mouse) followed by injection with PBS or zymosan (10 μg/cavity) 1 h later. Peritoneal exudate cells were harvested by peritoneal lavage 4 h and 24 h post-zymosan injection and processed as outlined in FIG. 7 . Z; zymosan, ChAB; anti-rmChemerin antibody. **, P<0.01 relative to zymosan-challenged mice. Reference in this figure to the peptide C15 refers to the peptide described previously as C15m;
[0109] FIG. 9 illustrates that injection of 0.32 ng/kg C15m alone does not induce neutrophil or macrophage recruitment but does reduce peritoneal TNFα levels. Reference in this figure to the peptide C15 refers to the peptide described previously as C15m;
[0110] FIG. 10 illustrates that a modified Chemerin13-human peptide suppresses RANTES and TNFα transcript expression in murine macrophages. Reference in this figure to the peptide hC13 refers to the modified C13h peptide;
[0111] FIG. 11 illustrates that C17m does not affect C140-induced macrophage chemotaxis. Reference in this figure to the peptide C17 refers to the peptide described previously C17m;
[0112] FIG. 12 illustrates that Chemerin15-mouse and Chemerin17-mouse suppress TNFα secretion by murine macrophages stimulated with Zymosan. Reference in this figure to the peptides C15 and C17 refers to the peptides described previously as C15m and C17m, respectively. Dexa refers to dexamethasone;
[0113] FIG. 13 is a checkerboard analysis demonstrating that Chemerin140 and Chemerin15-mouse induce true macrophage chemotaxis and not chemokinesis. Reference in this figure to the peptide C15 refers to the peptide described previously as C15m;
[0114] FIGS. 14A-B show that chemerin15 suppresses monocyte and neutrophil recruitment in zymosan peritonitis over a range of C15 and zymosan doses.
[0115] FIG. 14A shows C57B16/J mice (5-6 animals/treatment) were dosed i.p with PBS or C15 (0.32 ng/kg) followed by injection with PBS or zymosan dose range (10 μg-1 mg; A) 1 h later.
[0116] FIG. 14B shows Mice (5-6 animals/treatment) were dosed i.p with PBS or C15 dose range (4-40 pg/mouse followed by injection with PBS or zymosan (10 ng; 2×10 6 particles/cavity) 1 h later Peritoneal exudate cells were harvested by peritoneal lavage 4 h post-zymosan challenge; 5-6 mice/group). Total cell numbers in lavage fluid were quantified and cellular composition (Neutrophils vs mononuclear phagocytes) determined using FACS analysis as described in FIG. 7 . C15; Chemerin15, Z; Zymosan. ***, P<0.001; **, P<0.01 **; P<0.05 * relative to zymosan-treated animals Student's t test). Reference in this figure to the peptide C15 or chemerin15 refers to the peptide described previously as C15m; and
[0117] FIG. 15 shows fluorimetry for zymosan recognition by macrophages expressed as relative recognition index. Experiments were performed in the presence or absence of various concentrations of C15. Data represent mean (±s.e.m.) of four pooled, normalized experiments.
[0118] Reference herein to Chemerin140 or C140 is reference to the 140 amino acid mouse Chemerin protein (Chemerin-140-mouse) of Sequence ID no: 34.
DETAILED DESCRIPTION
Examples
Chemerin140 Exerts Anti-Inflammatory Effects on Activated Macrophages which are Abrogated by Protease Inhibitors
[0119] Previous studies have demonstrated that serine proteases released by polymorphonuclear cells (PMN) following degranulation cleave the C-terminal extremity of ProChemerin and release its chemotactic potential (Wittamer V et al. J Immunol. Jul. 1 2005; 175(1):487-493). However, the anti-inflammatory effect of peptides produced by further proteolytic processing of Chemerin is novel and inventive.
[0120] Murine peritoneal macrophages (PMθ, also referred to as PMΦ herein) were cultured under various conditions: Untreated; LPS (100 ng/ml) and IFNγ (20 ng/ml) for 15 h; Chemerin (1 pM) pre-treatment for 1 h then LPS/IFNγ for 15 h; Leupeptin (protease inhibitor; 15 mg/ml) and Chemerin (1 pM) for 1 h then LPS/IFNγ for 15 h; or Dexamethasone (positive control; 1 μM pre-treatment for 1 h then LPS/IFNγ for 15 h.
[0121] Supernatants from the Chemerin+lipopolysaccharide/interferon-γ (LPS/IFNγ)-treated macrophages were analysed for chemokine content and the results showed that chemerin treated cells displayed significantly lower levels of TNFα (70%), IL-12 p40 (54%), RANTES (CCL5; 40%), IL-6 (42%) and IL-1β (60%) compared to LPS/IFNγ-treated samples (n=5; p<0.001 FIGS. 1A and 1B ). This anti-inflammatory effect was inhibited by broad-spectrum protease inhibitors (leupeptin), which when added to the macrophages prevented any anti-inflammatory effect, illustrating the importance of additional Chemerin cleavage in the production of these anti-inflammatory peptides ( FIG. 1A and FIG. 1F ).
[0122] It was further demonstrated that these effects were Chemerin-specific by using an anti-Chemerin neutralizing antibody; which removed the anti-inflammatory effect of the Chemerin ( FIG. 8B ).
[0123] The bar graphs in FIG. 1A show the mean expression of cytokines as determined by the Luminex assay±SEM. Experiments were performed with triplicate determinations for each treatment. Representative data from three independent experiments employing cells from different groups of C57B16/J mice are shown. p<0.001 ***; p<0.01 ** relative to LPS/IFNγ-treated samples unless otherwise stated. Dexa refers to Dexamethasone (1 mM).
[0124] FIG. 1B shows similar results as discussed above in regard to FIG. 1A , with additional data showing the effects of chemerin at different concentrations of 0.1 pM, 0.5 pM and 1.0 pM.
[0125] In addition, FIG. 1C shows that chemerin induced the expression of mRNA for the anti-inflammatory cytokines TGFβ (54%) and IL-10 (89%).
[0126] The effects of chemerin were dose-dependent with maximal responses observed at 1 pM ( FIG. 1B and FIG. 1C ), and were pertussis toxin-sensitive, indicating the involvement of a Gαi-linked GPCR ( FIG. 1D ).
[0127] In addition, anti-inflammatory effects were observed at 4 h, 8 h, and 15 h after LPS/IFNγ administration and were abrogated by PTX at all time points ( FIG. 1E ).
[0128] Previous studies have demonstrated that serine proteases released by granulocytes following degranulation cleave the C-terminal extremity of prochemerin and release its chemotactic potential (Wittamer, V., et al., (2005), J Immunol 175:487-493). The possibility that murine chemerin could undergo further proteolytic processing by enzymes released upon murine MΦ activation was investigated. As discussed above in relation to FIG. 1A , coadministration of chemerin with Leupeptin (a serine and cysteine protease inhibitor) abolished its anti-inflammatory effects ( FIG. 1A and FIG. 1F ). This effect was also demonstrated for E-64 (a cysteine protease inhibitor), whilst the acidic protease inhibitor Pepstatin A and the serine protease inhibitor Pefabloc exerted no effect on chemerin-mediated suppression of MΦ activation ( FIG. 1F ). These data demonstrate that chemerin exerts inhibitory effects on MΦ activation in a cysteine protease-dependent manner. A cathepsin L inhibitor (Z-FF-FMK), cathepsin S inhibitor (Z-FL-COCHO) and a calpain I and II inhibitor, calpeptin were used to further probe the specific cysteine proteases involved in chemerin cleavage ( FIG. 1F ). It was found that chemerin's anti-inflammatory effects were dependent upon calpains and cathepsin S but was independent of cathepsin L. Taken together the results demonstrate for the first time that classically activated murine MΦ are capable of converting chemerin into potent peptide inhibitors of MΦ activation by specific cysteine protease-mediated cleavage of the parent molecule, most likely involving calpain II and cathepsin S.
[0000] C-Terminal Chemerin Peptides with Anti-Inflammatory Activity
[0129] A series of 11-20aa peptides were designed using sequence alignment functions in Ensembl as an indicator of important conserved residues and named C11m (P144-A154; PHGYFLPGQFA Seq ID No: 1), C13m (P144-S156; PHGYFLPGQFAFS Seq ID No: 3), C15m (A140-A154; AGEDPHGYFLPGQFA Seq ID No: 4) and C17m (A140-S156; AGEDPHGYFLPGQFAFS Seq ID No: 6) C19 (A138-5156; AQAGEDPHGYFLPGQFAFS Seq ID No: 37), N19 (E23-K41; ELSETQRRSLQVALEEFHK Seq ID No: 44) and M20 (K86-K105; KPECTIKPNGRRRKCLACIK Seq ID No: 45). FIG. 2A shows a sequence alignment for some of these peptides. Chemerin peptides (1 pM-100 nM) were characterized in the macrophage activation assay according to the described protocol.
[0130] Murine PMθ were cultured under various conditions: Untreated, LPS (100 ng/ml) and IFNγ (20 ng/ml) for 15 h; Chemerin peptides (at a concentration of 1 pM-100 nM) pre-treatment for 1 h then LPS/IFNγ for 15 h. The concentrations displayed represent the optimal effective doses for each peptide in both assays. The bar graphs in FIG. 2B displays mean expression of RANTES and TNFα protein±SEM. Experiments were performed with triplicate determinations for each treatment. Representative data from five independent experiments employing cells from different groups of C57B16/J mice are shown. p<0.01 **; p<0.001 *** relative to LPS/IFNγ treated samples.
[0131] C-terminal peptides C13m (100 pM), C15m (1 pM) and C17m (1 pM) suppressed LPS/IFNγ-induced RANTES secretion (C13m—32%; C15m—41%; C17m—49%) and TNFα expression (C13m—10%; C15m—56%; C17m—66%, FIG. 2B ). C15m and C17m inhibited macrophage activation to a similar extent as C140 when used at the same concentration.
[0132] Similar results are shown in Table 1, where C-terminal peptides C13 and C19 moderately suppressed LPS/IFNγ-induced RANTES and TNFα expression with an optimal dose of 100 pM (Table 1). Chemerin15 (C15), however, retained the anti-inflammatory activity shown by proteolysed chemerin and inhibited cytokine expression with similar efficacy and potency as chemerin (optimal dose 1 pM). In addition, C11, the N-terminal peptide (N19), midstream peptide (M20), and the control peptides (scrambled C15; C15-S, GLFHDQAGPPAGYEF; Seq ID No: 39, and mutant C15; C15-M, AGEDPHGYALPGQAA; Seq ID No: 40) were devoid of anti-inflammatory activity in the MΦ activation assay. It was also found that the 6 aa (RALRTK; Seq ID No: 41) and 8 aa (FSRALRTK; Seq ID No: 42) peptides removed during prochemerin cleavage by proteases of the coagulation and fibrinolytic cascades, named C6 and C8, respectively, possessed no detectable anti-inflammatory activity in the MΦ activation assay.
[0000]
TABLE 1
Percentage inhibition of LPS/IFNγ - induced inflammatory cytokine expression
Cytokine
Chemerin
C6
C8
C11
C13
C15
C16-6
C15-M
C19
M19
M20
TNFα
70
0
0
0
10
61
0
0
21
8
0
RANTES
40
0
0
0
32
47
0
0
41
5
0
L-1β
60
—
—
—
—
84
—
—
—
—
—
L-12 p4II
64
—
—
—
—
47
—
—
—
—
—
L-6
42
—
—
—
—
43
—
—
—
—
—
[0133] With reference to Table 1, anti-inflammatory activity of chemerin-derived peptides—Murine PMΦ were cultured as described for FIG. 1B and were challenged with LPS (100 ng/ml) and IFNγ (20 ng/ml) for 15 h with/without pre-treatment with peptides (0.1 pM-100 nM) for 1 h. Where peptides exhibited anti-inflammatory properties, percentage inhibition of LPS/IFNγ-induced macrophage activation represents effect with optimal dose (1 pM Chemerin and C15 or 100 pM C13 and C19). Peptide sequences are: C11 (P144-A154; PHGYFLPGQFA), C13 (P144-S156; PHGYFLPGQFAFS), C15 (A140-A154; AGEDPHGYFLPGQFA), C19 (A138-S156; AQAGEDPHGYFLPGQFAFS; Seq ID: No. 37), N19 (E23-K41; ELSETQRRSLQVALEEFHK Seq ID No: 44) and M20 (K86-K105; KPECTIKPNGRRRKCLACIK Seq ID No. 45). Control peptides: scrambled C15 (C15-S; GLFHDQAGPPAGYEF) and mutant C15 (C15-M; AGEDPHGYALPGQAA; F148A & F153A). Data represent mean percentage inhibition of cytokine production by classically activated macrophages from 4-8 independent experiments as determined by ELISA and Luminex assay.
Chemerin140, but not its C-Terminal Derived Anti-Inflammatory Peptides, is a Potent Macrophage Chemoattractant
[0134] Modified Boyden-chamber assays were utilized to demonstrate the macrophage chemoattractant properties of C140. Mouse Chemerin140 exhibits a typical bell-shaped curve with optimal chemotaxis observed at 10 nM, declining thereafter, presumably following receptor desensitization or breakdown of the chemoattractant gradient ( FIG. 3 ). This is also shown in FIG. 4A , with additional data showing the effects of Pertussis toxin pre-treatment (PTX: 200 ng/ml).
[0135] PMθ (0.5×10 6 ) were allowed to migrate towards chemoattractant (Chemerin140 or Chemerin peptides) in the bottom well of a modified Boyden chamber over 4 h. Filters were fixed in 4% formalin, then migrated cell nuclei were stained with DAPI and visualised. Serum free media (SFM) were used as a negative control and the macrophage chemoattractant RANTES (25 ng/ml; 3 nM) as a positive control. The graphs indicate mean Migration Index (Chemoattractant % threshold area/SFM % threshold area)±SEM for each treatment group (n=5-6). p<0.001 ***; p<0.01 **; p<0.05 * relative to SFM treated wells.
[0136] C11m, C13m and C15m (1 pM-100 nM) were observed to possess little chemotactic activity in comparison to C140 (1 pM-50 nM) or positive control the CC chemokine RANTES (25 ng/ml; 3 nM). Maximal macrophage migration was observed at 100 pM C15m and 10 nM C13m and C11m. C17m, however, displayed no chemotactic activity at all concentrations tested (0.1 pM-500 nM; n=5 independent experiments; ( FIG. 3 ). This result is also shown in FIGS. 4B-D , with additional data showing the effects of Pertussis toxin pre-treatment (PTX: 200 ng/ml). With reference to FIG. 4E , C19 also displayed no chemotactic activity at all concentrations tested (0.1 pM-500 nM; FIG. 4E ). Thus a chemerin-derived peptide has been identified that retains anti-inflammatory activity but exhibits no chemotactic activity for MΦs, indicating the existence of distinct function-specific components of chemerin that could be exploited therapeutically. The prochemerin-derived peptides, C6 and C8, which were found to be devoid of MΦ anti-inflammatory activity, were also incapable of inducing MΦ migration at all concentrations tested (0.1 pM-500 nM; FIG. 4F-G ). The data appears to therefore indicate that the principal chemotactic species is either the cleaved chemerin molecule itself, or an as yet unidentified peptide.
Additional Example Showing Chemerin and Chemerin15 Induce Generalized Suppression of Chemoattractant Production by Macrophages
[0137] Given the well established role of MΦ-derived chemoattractants in the recruitment of immune cells during inflammation (Glabinski, A. R., et al., (1998). Neuroimmunomodulation 5:166-171; Huang, D. J. et al., (2001). J. Exp. Med. 193:713-726), conditioned media was used from untreated MΦ and MΦ treated with chemerin+LPS/IFNγ, C15+LPS/IFNγ and LPS/IFNγ alone in chemotaxis assays to assess how suppression of MΦ activation by chemerin and the synthetic C-terminal peptide, C15 might affect further MΦ recruitment (See FIG. 4H ). Untreated MΦ-conditioned medium itself exhibited no chemotactic activity for MΦ (Migration index 1.0±0.15); however, LPS/IFNγ-treated macrophage medium induced a marked increase in MΦ chemotaxis (Migration index 9.3±0.4; FIG. 4H ). Furthermore, MΦs exhibited reduced chemotaxis towards conditioned media from chemerin+LPS/IFNγ and C15+LPS/IFNγ-treated macrophages by 49% and 55%, respectively ( FIG. 4H ). This indicates that chemerin and C15 induce general suppression of a broad range of MΦ-derived MΦ chemoattractants to the extent that the chemotactic activity of the conditioned media is affected.
[0138] Further secondary chemotaxis assays revealed suppressed macrophage chemotaxis towards supernatants from Chemerin140-mouse, Chemerin15-mouse and Chemerin17-mouse-treated macrophages. These results show that pre-treatment of activated macrophages with C15m and C17m decreases the amount and/or bioactivity of chemoattractants released by macrophages, and hence these peptides can significantly reduce continuing monocyte/macrophage recruitment to sites of inflammation.
[0139] Conditioned media from macrophages treated with C140+LPS/IFNγ, C15m+LPS/IFNγ, C17m+LPS/IFNγ and LPS/IFNγ alone were used in secondary chemotaxis assays to assess the potential pathophysiological repercussions associated with suppression of macrophage activation by C140 and its C-terminal peptides.
[0140] Cells (0.5×10 6 ) were allowed to migrate towards chemoattractant (Chemerin peptides) or conditioned media in the bottom well of a modified Boyden chamber over 4 h. Serum free media (SFM) was used as a negative control. Filters were fixed in 4% formalin, then nuclei were stained with DAPI and visualised. Bar graphs indicate mean Migration Index (Chemoattractant % threshold area/SFM % threshold area)±SEM for each treatment group. Each bar represents at least triplicate wells and 6 pictures taken per treatment. p<0.001 ***; p<0.01 ** significance is relative to LPS/IFNγ conditioned media unless otherwise stated. AB refers to anti-murine Chemerin antibody.
[0141] As can be seen from the results presented in FIG. 5 macrophage-conditioned medium itself exhibited no chemotactic activity for macrophages, however, LP S/IFNγ-treated macrophage medium induced a dramatic increase in macrophage chemotaxis. Furthermore, macrophages exhibited reduced chemotaxis towards conditioned media from C140+LPS/IFNγ, C15m+LPS/IFNγ and C17m+LPS/IFNγ-treated macrophages, indicating the ability of C140, C15m and C17m to induce general suppression of a broad range of macrophage chemoattractants.
[0142] To exclude the possibility that Chemerin-treated supernatants harboured Chemerin-derived chemotactic proteins/peptides, supernatants were incubated with a neutralizing Chemerin antibody prior to assessment of macrophage migration. Chemerin did not appear to contribute to migration in Chemerin-treated supernatants.
Chemerin15-Mouse Suppresses Zymosan-Induced Peritonitis
[0143] Peritoneal inflammation can be induced by intraperitoneal injection of Zymosan particles (a yeast cell-wall component) which elicit an acute inflammatory response. Zymosan-induced peritonitis follows a well-described time-dependent accumulation of neutrophils then monocytes in mouse peritoneal cavities (for review see Lawrence T et al. Nat Rev Immunol. October 2002; 2(10):787-795). This model has been utilized to demonstrate the pro-resolving properties of established mediators, Lipoxin A4 and annexin-1, which typically shorten the time course of inflammation with earlier restoration of tissue structure and function and suppression of neutrophil and monocyte extravasation. Previous experiments reported in the literature have used a range of doses of Zymosan A particles (10 μg-1 mg) (Taylor P R et al. Eur J Immunol. July 2005; 35(7):2163-2174; Arita M et al. J. Biol. Chem. Aug. 11, 2006 2006; 281(32):22847-22854).
[0144] Given the high chemotactic potential of chemerin and the inherent requirement for proteolysis, C-terminal synthetic peptide chemerin15 was used for in vivo characterization of anti-inflammatory effects in the sterile peritonitis model, since C15 is largely devoid of chemotactic activity ( FIG. 3 and FIG. 4B ) yet exerts anti-inflammatory effects that are comparable to those of proteolysed chemerin (Table 1).
[0145] With reference to the results shown in FIG. 6 , this study used 10 μg per mouse (1-2 particles per resident macrophage) as this is thought to more closely represent a pathophysiological dose.
[0146] More specifically, male C57B16/J mice (8-12 weeks) were injected intra-peritoneally with 0.5 ml PBS or 0.5 ml Chemerin15-mouse (0.32 ng/kg) followed by injection with 0.5 ml PBS or Zymosan (2×10 6 particles per cavity) an hour later. After 4 hours animals were sacrificed and peritoneal cavities washed with 5 ml PBS-3 mM EDTA. Total cell counts were obtained using Trypan blue exclusion test. For determination of cellular composition (Neutrophils vs mononuclear phagocytes), cells were blocked with 2.4G2 anti-FcgRII/III mAB for 5 mins and stained with PE-conjugated anti-mouse Ly-6G and FITC-conjugated anti-mouse 7/4 mAB for 10 mins. Cells were fixed in 1% formaldehdyde prior to FACS analysis with CellQuest software. Gates were constructed around two populations, the neutrophils (N; 7/4 high , Ly-6G high ) and inflammatory monocytes (Mo; 7/4 high ). C15 refers to Chemerin15-mouse. Z refers to Zymosan. p<0.01 **; p<0.05 * relative to Zymosan-treated.
[0147] Neutrophil (7/4 high , Ly-6G high ) monocyte (7/4 high , Ly-6G low ) and resident macrophage populations (7/4 low , Ly-6G low ) were determined according to Gordon S and Taylor P R Nat Rev Immunol. 2005; 5(12):953; Taylor P R et al. Eur J Immunol. August 2003; 33(8):2090-2097; and Taylor P R et al. Eur J Immunol. July 2005; 35(7):2163-2174.
[0148] The result of this study show that mice treated with C15m at a dose of 0.32 ng/kg (8 pg/mouse) exhibited reduced Zymosan-elicited monocyte and neutrophil recruitment by 42% and 52%, respectively ( FIG. 6 ). Levels of TNFα were also reduced in mice treated with C15m.
[0149] The above result was further investigated. To determine the anti-inflammatory properties of the C15 peptide in vivo a time-course experiment was performed extending over 48 h. Neutrophil (7/4high, Ly-6Ghigh) and monocyte (7/4high, Ly-6Glow) populations in peritoneal lavage fluid were determined by FACS analysis according to published protocols (Taylor, P. R. et al., (2005). Eur J Immunol 35:2163-2174; Taylor, P. R., (2003). Eur J Immunol 33:2090-2097). Administration of zymosan into the mouse peritoneal cavity produced a time-dependent extravasation of inflammatory cells into the peritoneal cavity, which followed the typical profile of an acute inflammatory response ( FIG. 7A-B , solid line). Neutrophils were the first leukocytes to infiltrate the cavity, detectable at 2 h post-zymosan with peak neutrophilia occurring at 4 h (1.95×10 6 cells). Monocyte influx into the inflamed peritoneal cavity was first detectable after 4 h (0.69×10 6 cells), peaking at 24 h post-zymosan injection (1.25×10 6 cells) and declining thereafter. Pre-treatment with C15 at a dose of 8 pg/mouse (≈0.32 ng/kg) 1 h prior to zymosan challenge brought the peak neutrophilia forward to 2 h with approximately 50% the magnitude of that of zymosan challenged mice (reduced from 1.25×10 6 to 0.62×10 6 cells; FIG. 7A , dotted line). Significant suppression of neutrophil infiltration by C15 was seen at 2 h, (50%), 4 h (66%) and 24 h (50%). A single dose of 8 pg of C15 peptide was also effective in reducing the number of peritoneal monocytes in inflamed cavities at all time points, with greater than 60% suppression seen at 4 h (63%), 8h (61%), and 48 h (64%; FIG. 7B , dotted line). The rate of monocyte infiltration was highest 2-4 h post-zymosan injection (0.51×10 6 /h) and administration of C15 reduced the rate of influx into the inflamed cavity (0.18×10 6 /h). A single dose of C15 peptide prior to zymosan-challenge therefore provided significant protection against zymosan-induced peritoneal inflammation over the 48 h duration of the experiment.
[0150] The time-course experiment identified the 4 h post-zymosan time point as an appropriate point for validation of C15's anti-inflammatory activity. In this study a single dose of C15 produced a dose-dependent reduction in zymosan-elicited neutrophil and monocyte recruitment which was maximal at 8 pg/mouse C15 (≈0.32 ng/kg; FIG. 7C-E and 16 A-B), although significant anti-inflammatory effects were seen with a dose as low as 4 pg/mouse (≈0.16 ng/kg; FIG. 14B ). When C15 was administered 1 h prior to zymosan-challenge neutrophil numbers were reduced from 1.9×10 6 to 0.78×10 6 (63% decrease; FIG. 7C ) and monocyte levels from 0.69×10 6 to 0.30×10 6 (62% decrease; FIG. 7D , representative FACS plots at the 4 h time point are shown in FIG. 7E ). C15 administration also markedly diminished the expression of pro-inflammatory cytokines in peritoneal lavage fluid at 4 h, including TNFα (51%), IL-1β (67%), IL-6 (67%), MCP-1 (59%), and KC (38%; FIG. 7F ). The control peptides C15-S and C15-M which were devoid of in vitro anti-inflammatory activity (Table 1) were also found to not be protective when administered in vivo at the same dose and time as C15 as judged by monocyte and neutrophil levels ( FIG. 7C-D ). Significant suppression of monocyte (0.69×10 6 to 0.42×10 6 cells; 42% decrease) and neutrophil recruitment (1.9×10 6 to 0.83×10 6 cells; 60% decrease) was still seen 4 h post-zymosan when the same dose of C15 was given 2 h post-zymosan injection ( FIG. 7G ). This demonstrates that C15 can reduce neutrophil and monocyte recruitment in an already established inflammatory setting, providing another indication that C15/C15-derivatives may represent attractive pharmacophores targeting inflammatory pathologies.
Blockade of Endogenous Chemerin Species Exacerbates Peritoneal Inflammation
[0151] A potential endogenous role for chemerin and chemerin-derived peptides was investigated by injecting mice i.p with a neutralizing polyclonal anti-rmChemerin antibody (ChAb) or a control IgG 1 h prior to a 4 h or 24 h zymosan challenge. It was previously found that ChAb but not control IgG was capable of inhibiting C15 and chemerin-induced MΦ chemotaxis and anti-inflammatory effects in vitro ( FIG. 8A-B ). In vivo it was found that neutralization of endogenous chemerin species resulted in a 63% rise in peritoneal neutrophil numbers and a 45% increase in monocyte levels at the 4 h time point relative to control IgG-treated mice and a 170% and 86% increase in peritoneal neutrophil and monocyte levels 24 h after zymosan injection ( FIG. 8C-D ). This exacerbation of peritoneal inflammation over a 24 h period suggests an important endogenous anti-inflammatory role for chemerin species in vivo.
[0000] Chemerin15-Mouse Alone does not Induce Neutrophil or Macrophage Recruitment but does Reduce TNFα Levels
[0152] Male C57B16/J mice (8-12 weeks) were injected intra-peritoneally with 0.5 ml PBS or 0.5 ml Chemerin15-mouse (0.32 ng/kg). After 4 hours three animals per treatment group were sacrificed and peritoneal cavities washed with 5 ml PBS-3 mM EDTA. Total cell counts were obtained using Trypan blue exclusion test. For determination of cellular composition (Neutrophils vs mononuclear phagocytes), cells were blocked with 2.4G2 anti-FcgRII/III mAB for 5 mins and stained with PE-conjugated anti-mouse Ly-6G and FITC-conjugated anti-mouse 7/4 mAB for 10 mins. Cells were fixed in 1% formaldehdyde prior to FACS analysis with CellQuest software. Gates were constructed around two populations, the neutrophils (N; 7/4 high Ly-6G high ) and inflammatory monocytes (Mo; 7/4 high , Ly-6G low ). C15 refer to Chemerin15-mouse. p<0.01 ** relative to PBS-treated. Ns refers to no statistically significant difference p>0.05.
[0153] As can be seen from the results in FIG. 9 , 0.32 ng/kg of C15m does not cause monocyte or neutrophil migration. However, a significant reduction in TNFα is observed.
[0154] This model, studying sterile peritonitis in mice is widely used in experimental medicine and pharmacology, and represents mild inflammation caused by moderate tissue trauma or infection. The results indicate that C15m is capable of achieving a therapeutic anti-inflammatory effect.
Modified Chemerin13-Human Suppresses Rantes and TNFα Transcript Expression in Murine Macrophages
[0155] Murine peritoneal macrophages (PMθ) were cultured under various conditions: Untreated, LPS (100 ng/ml) and IFNγ (20 ng/ml) for 15 h, modified Chemerin13-human (1 nM) pre-treatment for 1 h then LPS/IFNγ for 15 h. The bar graphs show the mean expression of cytokine transcript determined by qRT-PCR and normalised to housekeeper, hypoxanthine phosphoribosyltransferase, HPRT. Experiments were performed with triplicate determinations for each treatment, n=1 independent experiments. p<0.01 **; p<0.05 * relative to LPS/IFNγ-treated samples unless otherwise stated. The sequence of the modified C13h peptide is NH 2 -FHSFYFPGQFAFS-COOH (Seq ID No: 43)—in this sequence the N terminal P in C13h has been replaced with the amino acid F, and the peptide is therefore referred to as modified C13h.
[0156] As can be seen from the result in FIG. 10 , modified C13h significantly reduced expression of TNFα and RANTES.
[0000] Chemerin 17-Mouse does not Affect C140 Induced Macrophage Chemotaxis
[0157] PMθ were recruited following a 4 day peritoneal stimulation with BioGEL beads. Peritoneal cavities of male C57B16/J mice were lavaged with 5 ml PBS-2 mM EDTA. Cells were centrifuged and resuspended in RPMI supplemented with 0.5% BSA and 25 mM Hepes. Cells (0.5×10 6 ) were allowed to migrate towards chemoattractant (C140, C17m or C17m+C140) in the bottom well over 4 h. Filters were fixed in 4% formalin, then nuclei were stained with DAPI and visualised. Serum free media was used as a negative control (−/−). Cells were preincubated with Pertussis toxin (PTX) for 30 mins before the chemotaxis assay. The bar graphs in FIG. 11 show the mean Migration Index±SEM for each treatment group. Each bar represents at least triplicate wells and at least 3 pictures taken per treatment. p<0.001 ***; p<0.01 **; p<0.05 * relative to SFM treated wells unless otherwise stated.
[0158] The results in FIG. 11 show that co-administration of C17m with C140 did not appear to affect macrophage migration to C140.
[0000] Chemerin15-Mouse and Chemerin17-Mouse Suppress TNFα Secretion by Murine Macrophages Stimulated with Zymosan
[0159] PMθ were cultured under various conditions: Untreated; Zymosan for 15 h; Chemerin (1 pM) pre-treatment for 1 h+Zymosan for 15 h. The bar graphs show mean expression of TNFα as determined by ELISA±SEM. Experiments were performed with triplicate determinations for each treatment. Representative data from three independent experiments employing cells from different donors are shown in FIG. 12 . p<0.001 ***; p<0.01 ** relative to Zymosan-treated samples. Dexa refers to dexamethasone (1 mM), nd refers to below the lower limit of detection (0.25 ng/ml).
[0160] As can be seen, treatment with C15m (1 pM) and C17m (1 pM) suppressed Zymosan-induced TNF expression (C15m; 21%, C17m; 30%). C15m and C17m therefore suppress macrophage activation induced by both bacteria (LPS) and yeast (Zymosan A).
[0000] Checkerboard Analysis Demonstrates that Chemerin140 and Chemerin15-Mouse Induce Macrophage Chemotaxis not Chemokinesis
[0161] Checkerboard analysis allows differentiation between chemotaxis and chemokinesis. Chemotaxis is indicated by migration toward a higher concentration of chemoattractant in the lower well. Chemokinesis refers to increased non-directional cell movement and occurs regardless of the concentration gradient present. Checkerboard analysis was performed by pre-incubating cells with C140 (10-500 pM) or C15m (10-1000 pM) and allowing them to migrate towards C140 (10-1000 pM) or C15m (10-1000 pM), respectively in the lower well to form a checkerboard of concentrations.
[0162] More specifically, PMθ were recruited following a 4 day peritoneal stimulation with BioGEL beads. Peritoneal cavities of male C57B16/J mice were lavaged with 5 ml PBS-2 mM EDTA. Cells were centrifuged and resuspended in RPMI supplemented with 0.5% BSA and 25 mM Hepes. Cells (0.5×10 6 ) were incubated with C140 or C15m for 30 mins before the chemotaxis assay and then allowed to migrate towards chemoattractant in the bottom well over 4 h. Filters were fixed in 4% formalin, then nuclei were stained with DAPI and visualised. Serum free media (SFM) was used as a negative control (−/−) and the CC chemokine RANTES as a positive control (25 ng/ml). The bar graphs in FIG. 13 show the mean Migration Index±SEM for each treatment group. Each bar represents at least triplicate wells and at least 3 pictures taken per treatment. p<0.001 *** relative to SFM-treated wells.
[0163] It was found that C140 and C15m elicit true chemotaxis rather than chemokinesis as migration into the lower well of the Boyden chamber only occurred when a higher concentration of chemoattractant was placed in it and not when placed on the upper side of the filter.
[0164] C15m is shown to be a much weaker inducer of macrophage chemotaxis the C140.
C15 Induces Macrophage Phagocytosis of Zymosan
[0165] For in vitro recognition of zymosan by macrophages, peritoneal exudate cells were isolated by lavage with ice-cold 2 mM EDTA in PBS from mice that had been treated intraperitoneally 4 d before with Biogel beads (2% w/v). Macrophages were plated in 24-well plates at a density of 2.5×10 5 cells per well in Optimem medium. Cells were washed three times with medium before the addition of Fluorescein isothiocyanate (FITC)-labeled zymosan (Invitrogen) in recognition assays at macrophage/particle ratios of 10:1 in the presence of either 0.1 pM, 1 pM, 10 pM, 100 pM or 1 nM Chemerin15. Vehicle=control sample without Chemerin15. FITC-zymosan uptake was followed by FACS analysis and is expressed as a relative recognition index i.e the ratio of % cells uptaking zymosan×the ratio of geometric means C15 treated macrophages/geometric mean of macrophages treated with vehicle.
[0166] The results shown in FIG. 15 indicate that Chemerin15 induces macrophage phagocytosis of zymosan. The induction of macrophage phagocytosis is greatest at a Chemerin15 concentration of 10 pM. These results demonstrate that chemerin peptides may accelerate wound repair by increasing macrophage phagocytosis of apoptotic cells, cellular debris, pathogens and pathogen products.
Discussion
[0167] It is known that multiple mediators coordinate the initial events of acute inflammation. For example, lipid-derived eicosanoids, cytokines and chemokines regulate vascular alterations and inflammatory cell recruitment. Pro-inflammatory cytokines, including TNFα and IL-1γ activate signaling pathways in endothelial cells, resulting in upregulation of adhesion molecule expression, facilitating the capture of circulating leukocytes. The results presented above show that C-terminal peptides derived from Chemerin140 are able to suppress all of the components of the inflammatory response. The results also show that C-terminal peptides derived from Chemerin140 are able to reduce chemokines levels and could be used as a therapy for endotoxic shock.
[0168] All the peptides used in this study are Chemerin-derived, and display incredibly high potency (10 −12 M) which ensures that these mediators join the ranks of complement-derived chemotaxin, C5a des-arg (10 −12 M), formyl-Methionyl-Leucyl-Phenylalanine (fMLP; 10 −11 M), leukotriene B4 (LTB4; 10 −11 M) TNFα (10 −11 M), LPS (10 −15 M) and IL-1 (10 −14 M). The applicant know of no pharmaceutical preparations that have been demonstrated to exhibit physiological effects at 10 −11 M-10 −15 M. Indeed, dexamethasone is commonly administered at concentrations in the micromolar range in vitro and achieves 50% downregulation of monocyte and neutrophil influx in the Zymosan-induced peritonitis model at 30 μg/mouse (1.2 mg/kg). Chemerin15-mouse downregulated monocyte and neutrophil recruitment to a similar extent as 30 μg Dexamethasone. Chemerin15-mouse produces equivalent anti-inflammatory effects in this murine model of inflammation with a dose of only 8 pg per mouse (0.32 ng/kg).
[0169] Secondary chemotaxis assays allowed the chemotactic potential of supernatants from macrophage activation assays to be quantified, and the impact of Chemerin-mediated chemokine suppression on the chemotactic properties of the media to be determined. Analysis of these results revealed reduced macrophage migration towards supernatants from Chemerin+LPS/IFNγ-treated macrophages in comparison to LPS/IFNγ alone, indicating general suppression of a broad range of macrophage chemoattractants. The examples given demonstrate the limited or non-existent chemoattractant properties of Chemerin-derived anti-inflammatory peptides in comparison to C140.
[0170] In conclusion, the results show that C-terminal peptides of Chemerin exhibit extremely potent anti-inflammatory properties in vitro and in vivo.
Materials and Methods
Animals
[0171] All animal studies were conducted with local ethical approval and in accordance with the UK Home Office regulations (Guidance on the Operation of Animals, Scientific Procedures Act, 1986).
Antibodies and Reagents
[0172] Anti-human Chemerin, anti-murine Chemerin AB, hChemerin 137 (sequence ID no: 31, available from RandD as recombinant Glu21-Ser157), mChemerin 140 (Seq ID no: 34), anti-mRANTES Capture AB, anti-mRANTES Detection AB, mRANTES, mTNFα, anti-mTNFα Capture AB, anti-mTNFα Detection AB were purchased from R&D Systems. Chemerin peptides (C11m, C13m, C13h, C15m, C17m) were synthesised by biosynthesis (www.biosyn.com). Dexamethasone, Lipopolysaccharide ( E. coli ), Leupeptin were obtained from Sigma Aldrich. Interferon gamma (IFNγ) was purchased from Peprotech. OPD tablets were obtained from Dakocytomata, Streptavidin-HRP and StrepAv-HRP dilution buffer were purchased from Endogen. Luminex 6-plea kit (IL-12 p40, IL-1β, IL-6, MCP-1, TNFα, IL-10) was provided by Bio-rad and analysed using a Bio-rad bioanalyser and X software.
Inhibition of Macrophage Activation—Macrophage Activation Assay
[0173] 1 ml 2% BioGEL polyacrylamide beads in sterile Phosphate-Buffered Saline (PBS) were injected intraperitoneally (ip) into C57Bl/6J mice. Four days after ip BioGEL administration, mice were sacrificed by the CO 2 method according to Home Office guidelines. Peritoneal cavities were flushed with 10 ml sterile PBS-2 mM EDTA to harvest BioGEL-evoked/elicited cellular infiltrate. Suspensions of harvested cells were centrifuged at 1000×g for 5 mins at 4° C. The supernatants were discarded and cell pellets were resuspended in 6 mls OptiMEM medium supplemented with 2 mM Glutamine, 50 units/ml Penicillin and 50 μg/ml Streptomycin. Macrophages were quantified following incubation on ice for 5-10 mins with Turk's solution using a haemocytometer. Cell suspensions (2 mls; 1.5×10 6 /well) were plated in six-well tissue culture plates (35 mm diameter: Costar, UK) and allowed to adhere for 2 hours at 37° C. in a humidified atmosphere containing 5% CO 2 to isolate macrophage populations by adherence. This gave greater than 95% purity assessed by cytospinning, staining of cells with Methylene Blue and Eosin and counting based on cellular morphology. Nonadherent cells (mainly granulocytes) were discarded and wells were washed three times with sterile PBS to remove loosely adherent or dead cells. In order to evaluate potential suppression of macrophage activation and hence a reduction in the expression of pro-inflammatory mediators, macrophages (1.5×10 6 cells/well) were preincubated with Chemerin peptides (C11m, C13m, C15m, C17m; 10 −12 -10 −8 M) or positive control (Dexamethasone; 1 μM) for 1h and then challenged with LPS (100 ng/ml) and IFNγ (20 ng/ml) for 15 h. To determine PTX sensitivity and dependency upon proteolysis, cells were pre-incubated with PTX (200 ng/ml) or Leupeptin (15 μg/ml). Additional cells were treated with peptides alone. Supernatants were harvested and stored at −20° C. until use in Enzyme-Linked Immunosorbance Assays (ELISAs) and Luminex assays. Cells were lysed to allow extraction of total RNA by the TRIZOL method. Lysates were stored at −80° C. until RNA extraction following manufacturer's guidelines (Qiagen, RNeasy Mini Prep Kit).
Detection of Secreted Protein by ELISAs and Luminex
[0174] RANTES, Tumour necrosis factor (TNFα) and CCL9 concentrations in cell supernatants were assessed by ELISA. IL-12 p40, IL-10, IL-1β, TNFα, MCP-1 (Monocyte chemoattractant protein-1) and IL-6 levels were determined by Luminex multiplex bead assay (Bio-rad 6 plex assay). Lower limits of detection for ELISAs were 0.1-0.5 ng/ml and 10-50 pg/ml for Luminex assays.
RNA Preparation and RT-PCR
[0175] Total RNA was extracted using Qiagen RNeasy kits, reverse transcribed and subjected to qRT-PCR using the Sybr-Green method. Data was analysed using the 2-ΔΔCT method (Livak, K. J. & Schmittgen T. D. (2001), Methods 25:402-408).
Chemotaxis Assay
[0176] Cell migration was assessed by use of transwell membranes (ChemoTX, 6-mm diameter, 8-μm pore size). Briefly, BioGEL-elicited cells were harvested and placed on transwell membranes (250 000 cells/membrane in RPMI supplemented with 25 mM Hepes and 0.1% bovine serum albumin. Cells were allowed to migrate toward Chemerin peptides (1 pM-100 nM) for 4 h. Signal transduction via G protein-coupled receptors was blocked by preincubating cells with pertussis toxin (PTX, 200 ng/ml, Sigma-Aldrich) for 30 mins before placing cells on transwell membranes. Migrated cells on the underside of membranes were fixed (3% formaldehyde) and stained with DAPI. Migration was quantified as total pixel count of DAPI stained nuclei under the confocal microscope (2 photos/membrane and a minimum of 3 replicate wells per treatment). Images were analyzed using Metamorph Offline software to determine percentage threshold areas (TA) occupied by migrated cells. Migration indices were obtained by dividing treatment TA by serum-free media TA. For secondary chemotaxis assays ChemoTx 3-mm diameter, 8-μm pore membranes were used with 50 000 cells/membrane.
Murine Peritonitis
[0177] C57BL6/J mice were administered 500 μl Chemerin15-mouse (0.32 ng/kg) or vehicle alone (sterile PBS) i.p. 1 h before administration of 500 μl 10 μg Zymosan A i.p. After 4 h and humane sacrifice, peritoneal exudates were collected by peritoneal lavage with 5 ml of sterile PBS-3 mM EDTA. Cell-free lavage fluid was obtained for use in ELISAs and exudate cells were prepared for analyses described below.
Differential Leukocyte Counts and FACS Analysis
[0178] C57BL6/J mice were administered 500 μl Chemerin15 (0.32 ng/kg) or vehicle (PBS) i.p. 1 h before administration of 500 μl 10 μg Zymosan A i.p. After 2 h, 4 h, 8 h, 16 h, 24 h and 48 h and humane sacrifice. Aliquots of lavage cells were prepared for determination of total and differential leukocyte counts. For determination of cellular composition (PMN vs mononuclear cells), cells were blocked with anti-mouse 2.42G FcμII/III (0.5 μg/0.1×10 6 cells) for 10 min and stained (10 min) with FITC-conjugated anti-mouse 7/4 and PE-conjugated anti-mouse Ly-6G (0.5 μg/0.5×10 6 cells; clones rmCS-3 and RB6-8C5, respectively from BD Pharmingen). Cells were analysed on a FACSCalibur flow cytometer with CellQuest software. For each sample, a minimum of 10,000 events was acquired. Gates were constructed around three populations, the neutrophils (7/4 high , Ly-6G high ), monocytes (7/4 high , Ly-6G low ) and resident macrophages (7/4 low , Ly-6G low ). The percentage of total events in each population were measured. In addition, cell-free lavage fluid was collected for use in ELISA and Luminex assays.
Statistics
[0179] Student's t test and one way ANOVA were performed using GraphPad Prism software. | This invention provides the use of one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof for treatment of inflammation and/or endotoxic shock and/or treatment of wounds and/or reduction of levels of inflammatory chemokines in a subject, and one or more peptides derived from the C-terminal end of a Chemerin protein, or analogs or derivatives thereof for use in the treatment of inflammation and/or endotoxic shock, and/or wounds, or for the reduction of levels of inflammatory mediators. | 0 |
RELATED APPLICATIONS
[0001] This application claims priority from patent application under the Patent Cooperation Treaty PCT/US 01/09506, filed Mar. 23, 2001, which claims priority from U.S. Provisional Patent Application No. 60/192,065, filed Mar. 24, 2000.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] (Not applicable)
FIELD OF THE INVENTION
[0003] This invention relates to methods and systems for the accelerated decontamination of surface and/or subsurface regions with contaminated soil and/or contaminated groundwater.
BACKGROUND OF THE INVENTION
[0004] Contamination of soil and groundwater is a significant environmental hazard. Environmental and health concerns, as well as the need to comply with environmental laws and regulations, necessitate the use of methods and systems for the decontamination of soil and groundwater. Currently used decontamination systems are costly, time consuming and/or inadequate.
[0005] There are many conventional techniques for the removal of contaminants from soil, or from the vadose zone, or from groundwater, such as air stripping, pump and treat, bioventing, etc. It is widely recognized that such systems are inadequate for the timely or rapid decontamination of contaminated soil, vadose zone, and/or groundwater. This is because these systems often require several years to achieve minimal cleanup goals. For example, air stripping is a technique where contaminated groundwater is pumped out of the subsurface and passed over a stripping column, which provides a water-air interface that allows for the diffusion of contaminants out of the water and into the air. Even at sites with relatively low levels of contaminants, this technique is often projected to take as many as thirty years at the cost of multimillions of dollars to achieve cleanup goals. The main reason why most conventional methods fail to achieve cleanup goals cost-efficiently and in a timely manner is because the delivery system utilized usually impacts only portions of contaminated plumes in the soil, vadose zone, and/or groundwater, thus leaving sections of the contaminated plumes to naturally attenuate.
[0006] It is, therefore, be an advance in the art to provide a system for decontamination of contaminated zones in soil, vadose zone, or groundwater, using a method for decontaminating contamination in soil, in the vadose zone and/or in the groundwater, which is more efficient and more economical than currently available methods. It would also be an advance to combine all of the advantages of multiple techniques for the decontamination of contaminated soil, vadose zone and/or groundwater into one mobile treatment system. It would also be an advance to enhance the effectiveness of all methods contained in the mobile treatment system through the accompanying injection of heat and pure oxygen, and deliver the decontamination inputs from the treatment system in such a manner as to impact much more of the contamination plumes than currently available methods impact.
BRIEF SUMMARY OF THE INVENTION
[0007] The present invention provides for the accelerated removal of contamination from soil, the vadose zone, and/or groundwater. The contaminants are treated to render such less environmentally hazardous. The treatment involves vaporization and subsequent extraction, as well as oxidation and bioremediation. The products of the treatment system are less harmful, or not harmful to the environment, as compared to the contaminant, and thus the contaminant is deemed to have been treated to lessen an environmental hazard.
[0008] The present invention involves a method for removing contaminant from a matrix that comprises one or more of soil, a vadose zone, or a saturated zone. The method comprises the injecting an oxygen containing gas through at least one directionally, non-vertical disposed injection well passing through the matrix. The injection well or wells have a porous wall to enable the injection of the gas under positive pressure from the well into the matrix. Gas is then extracted from the matrix though at least one generally vertically disposed extraction well, the extraction well being under negative pressure and having a porous wall to enable the extraction of gas from the matrix into the extraction well. The injection well is disposed below contaminant material in the matrix to that as the gas rises through the matrix, gases produced in the matrix by interaction of the gas with contaminants are carried with the gas to the extraction wells. The injected oxygen containing gas to accelerates formation of gaseous or vaporized contaminant products that are carried along with the gas to the extraction well. The injection and extraction wells are disposed such that the zone through which the gas passes in the matrix between the injection well and the extraction well contains the contaminant material. The extracted gas it then treated to remove contaminant products in the gas derived from the contaminated material. The treated gas is then released into the atmosphere. The oxygen containing gas may be air, or may be oxygen enriched air, or comprise essentially pure oxygen. The gas contains sufficient oxygen to accelerate biodegradation and/or oxidative degradation of the contaminants.
[0009] The oxygen-containing gas may also contain microorganisms to introduce contaminant-degrading microorganisms into the matrix to accelerate biodegradation of the contaminant material and form gaseous degradation products to be carried away by the injected gas.
[0010] The oxygen-containing gas may also be heated to accelerate the volatilization of vaporized degradation products and warm the underground matrix and/or water to enhance biodegradation of the contaminant material to form gaseous degradation products. The heat may also be introduced into the saturated zone by withdrawing water from the saturated zone, heating the water, and reintroducing the heated water to the saturated zone.
[0011] As used herein, soil includes generally unconsolidated materials that are on the surface or below the surface. The vadose zone is that region between the surface and the water table. The saturated zone is below the water table where there is ground water.
[0012] As commonly understood in the industry, the soil is generally regarded as a separate zone. However, it is understood that there may be soil (unconsolidated materials) in the vadose and saturated zones, and contamination may extend onto that soil. Many hydrocarbons contaminants are lighter than water and generally float on the surface of the water table. However, there is some mixing at the interface of the water and the hydrocarbons, and soil in that area can become contaminated. Additionally, the water table in the subsurface fluctuates seasonally. As the water table raises and lowers floating contaminates can smear the soil. Therefore, at times of shallow water table fluctuations, there can be contaminated soil beneath the water table. Therefore, it is important to locate the injection lines beneath the zone of contamination based upon tests to characterize the plume.
[0013] Injection of the oxygen-containing gas results in residual soil gas containing contaminants. The soil gas is extracted through the extraction wells and is treated through a multitude of filtration methods, based upon site-specific conditions. For example, the removed contaminated soil gas can be passed through a vapor treatment system for injection into an aqueous medium, and subsequent separation through commonly available contaminant/water separators. Alternatively, the contaminated soil gas can be passed through granulated activated charcoal or some such other filter media for adsorption and subsequent disposal or treatment, or the contaminated soil gas can be oxidized through various methods such as thermal oxidation or ozonation. At any rate, any contaminated soil gas is decontaminated to below releasable levels as regulated by local statute before release to the atmosphere.
[0014] A feature of the present invention is an open circulated system so that the residual soil gas is not returned to the subsurface. By maintaining an open system, the effectiveness and cost-efficiency of treatment is increased. If the residual soil gas is returned to the soil the vadose zone, or the groundwater, as in certain prior-art methods, then there is that much more that must be treated over and over again. As an illustration, if 100 pounds of contaminant are present in one of the matrixes cited, and 20 pounds are removed via extraction system, then there are 80 pounds left in the matrix, if the 20 pounds extracted are treated separately and no portion thereof is returned to the matrix. If 10 pounds of it are returned or recirculated to the matrix, than there are still 90 pounds to treat. Additionally, if only non-contaminated air streams, atmospheric or pure oxygen in composition, are injected into the matrix, treatment efficiency rises due to an increase of electron acceptors for biodegradation in the soil, vadose zone, or groundwater, as well as due to simple dilutatory effects. An open circulated system is much more efficient than a closed circulated system.
[0015] In a preferred embodiment of the invention, the injection wells are placed at depths greater than the contamination zones/plumes, both parallel and perpendicular to the groundwater gradient and contaminant zone area. The vertical extraction wells are drilled in relation to specific flow characteristics of the soil and/or the vadose zone so as to extract resultant gases and vapors produced.
[0016] To accelerate the production of the gases and vapors, heated air is injected. The heat also increases the production of vapors produced by accelerated volatilization rates due to increased temperatures of soil and/or water from the heated air. In addition, an oxygen containing gas may be injected through a separate system. The oxygen-containing gas is enriched, or is pure oxygen to increase the bioremediation rates and production of gases produced therefrom.
[0017] The extracted gas is filtered and/or treated to reduce contaminant gasses and vapors to releasable levels as mandated by local regulations and released to the atmosphere, or otherwise treated and/or properly disposed of.
[0018] Contaminated Soil Remediation
[0019] Contaminated soil can be remediated by practice of the invention through the placement of directionally drilled injection wells throughout the soil profile, and one or more vertically drilled extraction well spaced in relation to the gas flow characteristics of the soil so as to extract vapors from the matrix, as well as gases introduced by the injection inputs. A positive pressure is induced in the injection wells, and a negative pressure is induced in the extraction wells. Injection inputs in the soil accelerate vaporization of contaminates. Vapors in the soil, originating either from the contaminate or induced through injection inputs in the soil, flow from the zones of high pressure induced by the positive pressure of the injection wells, to zones of low pressure induced by the negative pressure of the extraction wells.
[0020] Vadose Zone Remediation
[0021] A contaminated vadose zone is remediated by practice of the invention through the placement of directionally drilled injection wells throughout the soil profile, and one or more vertically drilled extraction wells spaced in relation to the soil gas flow characteristics of the vadose zone so as to extract vapors as well as gases induced by the injection inputs. A positive pressure is induced in the injection wells, and a negative pressure is induced in the extraction wells. Injected inputs in the soil, in the vadose zone, or in the groundwater accelerate vaporization of components in the contaminates. Vapors in the vadose zone, originating either from the contaminate or induced through injection inputs in the soil in the vadose zone, or groundwater, flow from the zones of high pressure induced by the positive pressure of the injection wells, to zones of low pressure induced by the negative pressure of the extraction wells.
[0022] Ground Water Remediation
[0023] Contaminated groundwater can be remediated by practice of the invention through the placement of directionally drilled injected wells below the zone of contamination and one or more vertically drilled extraction wells screened within a minimal distance above the most shallow depth of the groundwater and in relation to the soil gas flow characteristics of the vadose zone so as to extract vapors as well as gases induced by the injection inputs. A positive pressure is induced in the injection wells, and a negative pressure is induced in the extraction wells. Vapors in the soil or vadose zone, originating either from the contaminate or induced through accelerated volatilization of the contaminates caused by injection inputs in the vadose zone, or groundwater, flow from the zones of high pressure induced by the positive pressure of the injection wells, to zones of low pressure induced by the negative pressure of the extraction wells.
[0024] In an embodiment the invention, vertical water extraction wells are also drilled in relation to specific flow characteristics of the soil and screened in the area in-between impediment layers of inter-bedded varying soil textures so as to extract groundwater and thus capture gas from the injection wells and prevent such from moving laterally beyond the contaminant plume zone. The groundwater is then heated above the surface and re-injected to just below the most shallow area of the water table where vapors rising from such heated groundwater rise into the vadose zone and are extracted through the vertically drilled soil vapor extraction wells located therein. The extracted gases are then filtered and/or treated to releasable levels as mandated by local regulations and released to the atmosphere and/or treated and/or properly disposed of.
[0025] The extraction wells are normally vertically disposed but under certain conditions may be drilled horizontally. Extraction wells are horizontally disposed only under conditions that prevent vertical placement. For example, if contamination exists under a major road, it is not practical to vertically place the extraction wells under such circumstances. The same may be true if contamination exists under occupied commercial or residential buildings. Horizontal extraction wells may be more convenient than vertical extraction wells under such circumstances.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] [0026]FIG. 1 is a flow sheet and schematic diagram showing an embodiment of the invention for the accelerated decontamination of contaminated soil, vadose zone, and/or groundwater.
[0027] [0027]FIG. 2 is a schematic diagram that more particularly shows the placement of injection and extraction wells in an embodiment of the present invention.
[0028] [0028]FIGS. 3A, 3B and 3 C is another schematic diagram showing the movement of the pneumatic streams relative to the placement of injection and extraction wells in an embodiment of the present invention.
[0029] [0029]FIG. 4 depicts a system of the present invention showing the placement of wells in an embodiment as in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0030] The present invention is a system and method for the accelerated decontamination of soil, or the vadose zone, and/or groundwater. The accelerated decontamination involves the remediation of contaminants via extraction of contaminated vapors, as well as induced vaporization with subsequent extraction of contaminated vapors, as well as accelerated biodegradation of the contaminants. Contaminants may originate, for example, from leaking underground petroleum storage tanks used for gasoline, and/or diesel, and/or oil, and/or waste oil, and/or solvent storage, and/or other materials, or from spills from railroad tanker cars or freight truck trailers or large ocean going shipping vessels. Contaminants may also originate from leaking electrical transformers or from many other possible sources. Such contaminants may include one or more organic compounds such as benzene, toluene, xylenes, naphthalene, methyl tert butyl ether (MTBE), pentachlorophenol (PCP), polychlorinated biphenyls (PCB), poly aromatic hydrocarbons (PAHs), petroleum hydrocarbons, solvents, etc. These examples are illustrative, and the practical usages of this invention are not limited to these contaminants or strictly to organic contaminants. Scientific journals and technical publications are replete with articles and papers which identify contaminants of environmental concerns which can be remediated by the usage of the present invention.
[0031] Placement of Wells
[0032] Reference is now made to FIGS. 1, 2, 3 , and 4 . A principle feature of the present invention involves the delivery through directional (non-vertical) injection wells 31 , 33 of pneumatic injection inputs to surface soil or to the subsurface. Inputs injected via vertically drilled wells do not spread horizontally across a large area, but instead rise in the path of least resistance, most often straight up along the well bore. Commonly known pneumatic principles dictate that even in the presence of a vertically drilled extraction well exhibiting a negative pressure a pneumatic stream injected into a vertical injection well will rise straight up unless the negative pressure of the extraction well is great enough or close enough to overcome the resistance of the media into which the pneumatic stream is injected, or the media itself channels the pneumatic stream to the extraction well. This means that most often for communication between vertically drilled injection and extraction wells to be established, such wells have to be drilled so close together as to make usage of such cost-prohibitive due to the large numbers of wells required to treat a given contaminated area.
[0033] By utilizing directional, non-vertical or generally horizontal wells to inject the pneumatic inputs 31 , 33 and one or more vertically drilled wells 35 to extract the soil gases, communication between extraction and injection wells is easily established. The injection inputs from the wells rise vertically along the horizontal plane of the injection line and are twisted toward the vertical plane of the extraction well when the pneumatic streams encounter the negative pressure of the vertically drilled extraction well. (See particularly FIG. 3.)
[0034] All well spacing is placed according to specific soil texture and porosity data at any given site, as well as according to contaminate spatial configuration in the soil, the vadose zone, and/or the groundwater. Injection or extraction wells used for the invention typically are drilled and constructed with annular space filled with filter media and capped at the surface with cement and bentonite. The filter media may extend along the entire length of the well, from the bottom of the well up to the cement or bentonite. The well screen is the porous portion of the well. The well screen is configured relative to contaminate location and soil water characteristics. In horizontal wells, the well screen is limited to that portion of the well line that levels off beneath the contamination. The reason for this is that horizontal, or directional drilling is often performed in a U shape. That is, the surface is penetrated and the drill bore is directed at an angle for a specific distance until the target depth is reached, whereupon the drill bore levels off for a specific targeted length, whereupon the drill bore angles back up toward the surface where it exits. The plumbing is pulled back through the borehole from that exit point. It is necessary to limit the portion of the plumbing that is porous (screened) to the section of the borehole that is horizontally level because if porosity is included in the angled approaches into and out of the soil, pneumatic inputs will all exit there, since air always travels to the highest section of the container. Therefore the section of plumbing used in the angled approaches is blank that is it is not perforated or screened. Only the horizontally level sections of the plumbing in the injection wells are screened. Additionally, if horizontal extraction wells are used, they can be “plugged,” i.e., plugs can be placed along the line in various areas to control the extraction points of the well.
[0035] Reference is now made particularly to FIGS. 2 and 3. FIG. 2 shows a top view of six injection wells, 31 , 33 surrounding an extraction well. Gas from the injection wells from the positive pressure is directed into and passes through the matrix 37 , which may be soil, the vadose zone, or groundwater in the saturated zone. Because of the negative pressure on the extraction well 35 , the gasses are directed toward the extraction well, as illustrated by the flow arrows 39 .
[0036] Reference is now particularly made to FIG. 3A, FIG. 3B, and FIG. 3C, which show a single injection well 31 and a single extraction well 33 for simplicity. FIG. 3A is a top view, as in FIG. 2. FIG. 3B shows a side view of the same system. FIG. 3C shows the same system in a three-dimensional view. As shown, gas (shown as circles) 41 is injected from the injection well by positive pressure and directed through the matrix 37 toward the extraction well 35 (as shown by the flow arrows 39 ). As shown more clearly in FIG. 3C, the zone in which the gas flows forms a relatively large three-dimensional treatment zone 43 in the general form of a pyramid. If the injection well were vertical, the volume of the treatment zone would be much smaller, and resembling more a two-dimensional thin vertical plane. With the directionally aligned injection well 31 , a large three-dimensional region can be defined to include contaminated zones. From this illustration it can be seen how placement of several directional injection wells with vertical extraction wells can be used to define a suitable three-dimensional region or regions, as dictated by the location of the contamination, and other matrix properties.
[0037] Reference is now made particularly to FIG. 1. Contaminants may be located in soil, in the vadose zone and/or in the groundwater zone. The vadose zone is the subsurface zone between the groundwater and the surface. Soil gas is drawn into extraction wells 35 from the surrounding soil or vadose zone due to the negative pressure generated by extraction blower 57 . Soil gas extracted through wells is passed through a filtration unit in the treatment system 53 via lines running from the extraction wells 35 to the bottom of the treatment system 53 .
[0038] The treatment system 53 serves as a means for adsorbing and/or rendering the soil gas from the extraction wells non-hazardous to the environment, so that it can subsequently be released through conduit 55 . The soil gas, which contains products from biodegradation, oxidation, and volatilization of the contaminants in the soil, is introduced at the bottom of the filtration unit in the treatment system 53 so as to contact the maximum amount of surface area for most efficient adsorption residence time.
[0039] Injection inputs are obtained via two routes from the system. Atmospheric air is heated via passage through an injection blower 51 , which has a heater capable of generating heated air with a temperature up to 350° F., and provides the positive pressure for injection into injection wells 33 . The heated air stream from the blower 51 is introduced into the matrix 37 via directionally drilled injection wells 33 . This heated air stream provides oxygen for electron acceptance for biodegradation of contaminants by indigenous bacteria and/or augmented bacteria. This heated air stream also stimulates bacterial degradation of contaminants through adjustment of the soil or vadose zone and/or groundwater temperatures to levels more optimum for bacterial metabolic processes. Injecting heat decreases the viscosity and increases the solubility of contaminants. This heated air stream also increases the rate of vaporization of the contaminants due to increased vaporization in the presence of increased temperature. Injecting heat into the saturated zone creates conduction and/or convection currents as the rising column of heated air removes contaminants from the water. Injecting heat makes the present invention much more efficient for the decontamination of contaminated soil 45 , vadose zone 47 , and/or groundwater 49 than currently available options. Heat can also be introduced into the groundwater zone 49 by withdrawing water, heating the water, and reinjecting the water as further described herein.
[0040] A second route of injected inputs through injection wells 31 supplied via an oxygen generator 59 . The oxygen generator is fed by a compressor 60 . The compressor 60 also provides the positive pressure required for injection of the gas through the injections wells 31 . 92% pure oxygen is generated by the oxygen generator 59 and introduced into the soil 45 or vadose zone 47 and/or the groundwater 49 via directionally drilled wells 31 separate from those wells 33 used for the heated air stream. The 92% pure oxygen stream stimulates bacterial degradation of contaminants through providing a substantial increase of quantity of electron acceptors for oxidation of contaminants. It is calculated that it takes 2 pounds of oxygen to degrade 1 pound of hydrocarbon. One type of oxygen generator 59 utilized in the invention delivers 471 pounds of oxygen per day. Injecting 92% pure oxygen at relative high rates makes the invention much more efficient for the decontamination of contaminated soil 457 vadose zone 477 and/or groundwater 49 than currently available options.
[0041] The 92% pure oxygen can be first passed through a bioreactor 61 . Such passage will impregnate the 92% pure oxygen stream with contaminant degrading bacteria and accompanying nutrients, and introduce both to the matrix 37 . The microorganisms used in the bioreactor 61 can include any microorganisms effective for the biodegradation of the contaminants. Microorganism varieties can be chosen from market place sources or through literature research, or field collection. In addition to effective bacteria, other microorganisms, such as enzymatic agents which are effective for the biodegradation of contaminants can be used in the practice of the invention. The term “microorganism” is intended to be used to describe any enzyme produced by a microorganism, or any derivative from a microorganism, which is effective for the biodegradation of the contaminants.
[0042] Preferably the microorganisms utilized are aerobic contaminant degrading Pseudomonas spp. bacteria. Pseudomonas spp. bacteria are especially effective for the biodegradation of organic contaminants, such as benzene, toluene, xylenes, MTBE, PCBs, jet fuel, diesel, gasoline, oil, etc. Aerobic bacteria are active in the presence of oxygen. Such bacteria biodegrade the contaminants by metabolizing organic material to obtain energy to reproduce more bacteria. Carbon dioxide and water vapor are among the by-products of such biological processes. Some undigested solids may also remain after the process has ceased. The bacteria utilized are preferably pre-acclimated to the contaminants as carbon source. Pre-acclimation can be achieved via supporting the varieties of choice upon the targeted contaminant or contaminants for a period of time prior to introducing the bacteria to the matrix 37 . The bacteria over time become dependent upon the contaminants as their sole carbon sources. Bacterial strains which can digest the contaminants in the matrix 37 thrive and will die from the contaminants. As a result of such pre-acclimation, strains can be supplied the matrix 37 which are especially effective for degradation of the targeted contaminants.
[0043] Nutrients and catalysts can be supplied the bacteria in the nutrient tank 63 as means for stimulating indigenous and/or augmented varieties for greater population growth and increased degradation rates. Nutrients and catalysts that specifically preferred by the microorganisms utilized are preferable. Catalysts which increase the metabolic rates and provide aleomorphic characteristics for the microorganisms utilized are preferable. The nutrients are metered from the nutrient tank 63 into the bioreactor by means of a metering pump 65 .
[0044] Miscellaneous system components such as blowers 51 , 57 , nutrient tanks 63 , metering pumps 65 , oxygen generators 59 , air compressors 60 , etc. can be obtained from common commercial sources.
[0045] Reference is now made to FIG. 4. FIG. 4 illustrates how the system illustrated in FIG. 1, may be configured. The above ground equipment, such as the blowers 51 , 57 , filters 53 , nutrient tanks 63 , bioreactors 61 , air compressors 60 , oxygen generators 59 , and the like are placed together in a single shelter 67 , which may be mobile for movement from site to site. The injections wells 31 , 33 are directed into and preferably under the zone of contamination 69 . The vertical extraction wells 35 communicate with equipment in the shelter 67 by extraction lines 71 from the heads of vertically drilled wells. Heated air (shown by crossed circles 79 ) from the heated air injection wells 33 travels through the matrix 37 , which in this illustration is a saturated zone 49 , and vadose zone 47 , toward the extraction wells 35 . The heat also tends to spread through the matrix 37 , carried by conduction and the flow of the gas and water, as illustrated by the wavy lines 73 . The extraction wells 35 are disposed above the saturated zone 49 , as it is not desired to draw water into the extraction wells.
[0046] In the second injection system, oxygen-enriched gas contains microorganisms (shown by O-circles 81 ) travels from injections wells 31 , through the matrix 37 , to the extractions wells 35 . From the extraction wells 35 is drawn gas injected through the injection wells 31 , 33 , as well as gas products from the contaminants. The gas from the extractions wells 35 is passed through the treatment system 53 to remove harmful substances to safe concentrations and then is passed into the atmosphere though conduit 55 . Accordingly, the only “product” of the system is a gas stream that has been treated to remove contaminants, and is ejected into the atmosphere.
[0047] The figures illustrate a preferred system with two injection systems, because bacteria in the preferred system are not compatible with air heated to a temperature greater than 110° F. However, it is contemplated that only one injection system or any number of injection systems be used, depending upon the nature of the treatment. For example, applying heat may not be required in some locations, where a separate injection system of heated air can be avoided. In addition, other treatment systems which are not compatible can be injected separately as required.
[0048] An alternate embodiment is also shown in FIG. 4. In addition to the gas/vapor extraction wells described above, a water extraction well 75 is provided to draw water from the contaminated zone 69 in the saturated zone 49 . This may be desired to prevent the plume of contaminants in the water from spreading laterally through a water porous layer between two impediment or non-porous layers. The water is then heated by apparatus in the shelter 67 and injected through a water injection well 77 . The heat from the water accelerates the production of vapor and improves the temperature of the matrix for biodegradation the same way as the heat introduced by heated gas.
[0049] The foregoing description of the invention and the accompanying drawings so fully reveal the combination of methods, the specialized delivery system and the unique heat and oxygen inputs, and the general nature of the invention, including its advantages and modifications, that anyone could readily modify the invention and/or adapt it for various applications without departing from its general concepts. Therefore, such adaptations and modifications should be, and are intended to be comprehended within the meaning and range of the claims appended hereto and their equivalents, which claims define subject matter regarded to be the invention described herein. | A system and method for the accelerated decontamination of contaminated soil, vadose zone and/or groundwater is described. Contaminates are removed from soil and from the groundwater via heat injection through trenching or directionally drilled or horizontally drilled and installed delivery plumbing, pure oxygen injection through separate plumbing installed in the same manner as the plumbing used to deliver the heat, bioventing, sparging, and bioremediation, all through the oxygen delivery plumbing, and soil vapor extraction through vertical wells, all contained in one mobile treatment system. Contaminants are separated from the soil gas via filtration or oxidation. Residual contaminants in the vadose zone and/or the in the groundwater are subjected to volatilization by increased temperature via heat injection and/or oxidation via contaminant degrading microorganisms. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of copending International Application No. PCT/DE99/02435, filed Aug. 5, 1999, which designated the United States.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a turbine casing having an inner casing and an outer casing which surrounds the inner casing to form an intermediate space.
[0004] The turbine casing of, for example, a steam turbine is usually built up from an inner casing and an outer casing surrounding the inner casing to form an intermediate or annular space. The two casing parts respectively have, in turn, an upper half and a lower half. Particularly after the turbine has been shut down, temperature differences appear on the casings and between them and these differences can be more than 50° K. between the lower half and the comparatively hotter upper half. If the turbine is shut down, the outer casing cools more rapidly than the inner casing. Because of this, due to free or natural convection in the intermediate space, an upward flow is induced between the inner casing and the outer casing and this causes an input of heat into the upper half of the outer casing. This can, in turn, lead to casing distortion, particularly in the upper half of the outer casing, with the result that undesirable casing material stresses and clearance closures occur there. A distortion of the inner casing also can lead to undesirable rubbing damage if, in unfavorable cases, turbine blades rub on the casing.
[0005] Published, Non-Prosecuted German Patent DE 34 20 389 A1 discloses a steam turbine having an inner casing and an outer casing surrounding the inner casing, an intermediate space being formed by this double-shell casing construction. In its axial extent, the inner casing is at least partially covered by a shell that is disposed in the intermediate space.
[0006] At an inlet end, the shell is connected to a piston seal and, at an outlet end, the shell has a plurality of openings distributed around the periphery. During operation of the steam turbine, the shell ensures that the relatively cold exhaust steam cannot flow around the inner casing. For this purpose, hot steam that is taken from the piston seal flows between the shell and the inner casing. This causes a heat build-up effect in the space formed by the shell and the inner casing so that the inner casing is substantially protected from excessive cooling by the cold exhaust steam. This serves to avoid different temperature loadings on the inner casing and therefore reduces thermally induced deformations of the same, in particular during start-up and in load-change operation.
[0007] U.S. Pat. No. 5,388,960 describes a device for the forced cooling of a single-flow steam turbine. The steam turbine has a double-casing construction with an inner casing and an outer casing surrounding the inner casing to form an intermediate space. After the flow of live steam has been switched off, the steam turbine is brought to a desired cooled temperature in the shortest possible time by a cooling device. For this purpose, atmospheric air is induced, compressed and cooled in a heat exchanger. The air pretreated in this way is supplied to the intermediate space for cooling purposes by a respective inlet opening in the upper casing half and the lower casing half of the outer casing. After flowing through the intermediate space in the axial direction, the air passes via the outlet-flow connection of the steam turbine out of the intermediate space again and is released via an outlet valve. In this configuration, temperature differences which occur between the upper casing halves and the lower casing halves, which appear as a consequence of uneven cooling-air flow, as well as axial differential expansions, are monitored by appropriate measuring devices. The measurement signals are used for controlling the cooling transients.
SUMMARY OF THE INVENTION
[0008] It is accordingly an object of the invention to provide a turbine casing which overcomes the above-mentioned disadvantages of the prior art devices and methods of this general type, in which a distortion of the outer casing is prevented or at least reduced, in particular during cooling of the turbine.
[0009] With the foregoing and other objects in view there is provided, in accordance with the invention, a turbine casing. The turbine casing has an inner casing and an outer casing surrounding the inner casing and defining an intermediate space there-between, the outer casing has a first opening and a second opening formed therein. A circulating fan system connects the first opening to the second opening so that a forced flow of a medium located within the intermediate space can be generated. The first opening, the second opening, the intermediate space and the circulating fan system together define a closed circuit.
[0010] The first-mentioned object is achieved, according to the invention, by a turbine casing having an inner casing and an outer casing surrounding the inner casing to form an intermediate space. A first opening and a second opening are formed in the outer casing. The first opening is connected to the second opening by a circulating fan system, so that a forced flow of the medium located within the intermediate space can be generated in a closed circuit formed from the casings and the circulating fan system.
[0011] The object directed towards a method is achieved, according to the invention, by a method that avoids a casing distortion of the turbine casing when the turbine is shut down. More specifically, in the intermediate space formed between the inner casing and the outer casing surrounding the inner casing, a forced flow of the medium located in the intermediate space is generated in the closed circuit in order to even out the temperature distribution in the turbine casing.
[0012] The invention follows from the consideration that evening out of the temperature distribution, particularly in the outer casing, can be achieved by acting against the free convection flow arising in the intermediate space between the inner casing and the outer casing. The convection flow (natural convection) namely leads, on the one hand, to temperature differences between the casing parts, in particular between the two casing halves of the outer casing, and to the formation of upwardly directed convection streaks on the other. These, in turn, cause a local heat input, mainly at a vertical apex point of the intermediate space, into the upper half of the outer casing. It is possible to act against this effect in a suitable manner by an active circulation or eddying of the medium within the intermediate space so that a convection flow no longer builds up.
[0013] For this purpose, the medium is guided in a circuit that is expediently closed by a ducting system outside the turbine casing. In order to generate a forced and directed flow, a circulating fan is provided whose suction side and whose pressure side are respectively connected to an opening in the outer casing. The suction-side opening forms an outlet-flow opening for the medium whereas the pressure-side opening forms an inlet-flow opening. The inlet-flow opening and the outlet-flow opening are respectively configured as connection openings in such a way that an inlet-flow duct can be connected to the inlet-flow opening and an outlet-flow duct can be connected to the outlet-flow opening.
[0014] It is particularly advantageous for one of the openings to be provided in the lower half of the outer casing and for the other opening to be provided in the upper half of the outer casing. In a coordinate system intersecting in the central middle axis of the turbine casing, the two openings are, for example, in the second and fourth quadrants and are diametrically opposite. It is also possible for the first opening to be disposed in the first quadrant and the second opening to be disposed in the third quadrant. The inlet-flow opening is preferably provided in the upper half and the outlet-flow opening is provided in the lower half of the outer casing. Due to the two connection openings on the turbine casing and due to a corresponding duct routing with the circulating fan employed, only a very slight additional operative complication occurs overall. In a preferred embodiment, the outer casing is in two parts, the upper half being formed by an upper part and the lower half being formed by a lower part, the upper part and the lower part being connected together by a split joint.
[0015] The turbine casing is advantageously employed as the casing of a steam turbine. Applications of the turbine casing are particularly suitable both for high-pressure steam turbines and for medium-pressure steam turbines. In these, the temperature of the hot steam that drives the turbine is between approximately 300° C. and 700° C. The material of the casings, in particular the inner casing, is subjected to these high temperatures. The heat stored in the inner casing and in the outer casing must be removed as evenly as possible from the casings after the steam turbine is shut down, i.e. after the steam flow in the turbine is switched off. In the case of a high-pressure steam turbine, the turbine casing specified can be advantageously employed because of the generally very compact construction and the associated high heat flow density through the inner casing and outer casing. In a medium-pressure steam turbine, it is mainly the relative length changes occurring over its larger dimension which is critical for casing distortion after the turbine is shut down. These critical thermal expansions are effectively avoided by the turbine casing specified above. In addition to the applications in high-pressure and medium-pressure steam turbines, employment possibilities in the case of low-pressure steam turbines also arise.
[0016] The advantages achieved by the invention relate, in particular, in the fact that the evening out of the temperature distribution in the outer casing occurs in a particularly simple manner due to a forced, preferably directed flow of the medium in the intermediate space of the turbine casing built up from the inner casing and from the outer casing surrounding the inner casing.
[0017] In this configuration, the natural convection usually occurring during shut-down of the turbine is reliably prevented and a temperature difference between the outer casing and the inner casing and, between the upper half and the lower half of the outer casing, are kept small so that a casing distortion, a so-called cat's back, is reliably avoided. The additional complexity in terms of apparatus necessary for generating the flow can be kept particularly small, especially since only one circulating fan is necessary for an active circulation or eddying of the medium, for example air, located in the intermediate space. A circulating fan is advantageously located within a ducting system routed outside the turbine casing.
[0018] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0019] Although the invention is illustrated and described herein as embodied in a turbine casing, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
[0020] The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
[0021] The single FIGURE of the drawing is a diagrammatic, sectional view of a turbine casing according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] Referring now to the single FIGURE of the drawing in detail, there is shown a turbine casing 1 of, for example, a steam turbine 2 whose further components, for example its turbine shaft and turbine blades, are not shown for simplicity. The turbine casing 1 has an inner casing 3 and an outer casing 4 which surrounds the inner casing 3 , preferably concentrically. The inner casing 3 and the outer casing 4 are then at a distance from one another in such a way that an intermediate space 5 is formed. The intermediate space 5 is filled with a gaseous medium L, for example air, which is capable of convection. The inner casing 3 and the outer casing 4 can be respectively subdivided into a first, upper partial region or upper half 6 , and into a second, lower partial region or lower half 7 . The inner casing 3 and the outer casing 4 can be respectively configured in two parts, the upper half 6 being formed by an upper part 6 A and the lower half 7 being formed by a lower part 7 A. The upper part 6 A and the lower part 7 A are then connected together by a split joint 20 that extends for example along the X axis.
[0023] If a heat flow through the turbine casing 1 is considered, there is an inner heat flow Qi through the inner casing 3 and an outer heat flow Qa though the outer casing 4 . In addition to a radiation heat flow QS, which acts from the inner casing 3 onto the outer casing 4 , a thermal convection flow QK appears between the inner casing 3 and the outer casing 4 . If the turbine 2 were shut down, a free or natural convection flow—designated below as the natural convection QN—would occur whose thermal flow course is shown by the interrupted line provided with arrowheads. Particularly in the region of the apex of the intermediate space 5 , the natural convection QN would lead to the formation of a convection streak symbolized by an arrow 8 with a local heat input into the outer casing 4 in the region of its upper half 6 . A local heat input of this type can, as a consequence of high thermal loading, lead to an undesirable casing distortion.
[0024] The formation of such a natural convection QN, which would in addition lead to a temperature difference ΔT AG between the upper half 6 and the lower half 7 , is prevented by a directed flow, symbolized by a full line S, being actively generated and therefore being forced in the intermediate space 5 .
[0025] For this purpose, the outer casing 4 has two, preferably diametrically opposite, openings 9 , 10 which are in connection with one another by use of a circulating fan 12 provided within a ducting system 11 .
[0026] In the exemplary embodiment, the first connection or inlet-flow opening 9 is provided in the second quadrant of a (virtual) XY coordinate system intersecting on a turbine longitudinal axis 13 . The second connection or outlet-flow opening 10 is then located in the fourth quadrant of the XY coordinate system. The outlet-flow opening 10 can also be located in the third quadrant. A plurality of the openings 9 , 10 can also be provided. As an example, the inlet-flow opening 9 can be provided in the second quadrant and two of the outlet-flow openings 10 can be provided in the first and third quadrants. It is also possible for a plurality of the openings 9 , which are the inlet-flow openings 9 for the medium L, to be provided. These are then advantageously disposed on the upper half 6 of the outer casing 4 .
[0027] In the configuration, a suction side of the circulating fan 12 is connected by the ducting system 11 to the connection opening 10 provided in the lower half 7 of the outer casing 4 . The pressure side of the circulating fan 12 is then connected by the ducting system 11 to the connection opening 9 located in the upper half 6 of the outer casing 4 .
[0028] The circulating system for generating the forced flow S through the intermediate space 5 of the turbine casing 1 is advantageously put into operation after the turbine 2 has been shut down. When the circulating fan 12 is running, the medium L located in the intermediate space 5 is guided out from the intermediate space 5 via the connection opening 10 and is guided back into the intermediate space by the ducting system 11 and the circulating fan 12 via the connection opening 9 . Overall, therefore, a closed circuit 14 is provided by the intermediate space 5 and the ducting system 11 .
[0029] The formation of the free convection or the natural convection QN is prevented by the forced flow S of the medium L in the intermediate space 5 so that the temperature difference ΔT AG arising between the upper half 6 and the lower half 7 of the outer casing 4 is substantially avoided or at least kept as small as possible. The forced flow S, however, primarily causes an evening out of the temperature distribution in the outer casing 4 .
[0030] Therefore, temperature gradients are substantially prevented and relative thermal expansions, in particular between the upper half 6 and the lower half 7 , and thermal stresses are therefore limited.
[0031] Because of the evening out of the temperature distribution in the outer casing 4 effected by the forced flow S, therefore, action is taken against the natural convection QN in such a way that casing distortions are reliably prevented after shut-down during cooling of the turbine 2 , for example of a steam turbine 2 . | A turbine casing has an inner casing and an outer casing which surrounds the inner casing to form an intermediate space. In order to avoid a casing distortion, a forced flow of a medium located within the intermediate space is provided. A method is also described which relates to avoiding a temperature based casing distortion during the shut-down of a turbine. | 5 |
BACKGROUND
The present invention relates to storage and network communication systems.
RELATED ART
Adapters are commonly used by computing systems for sending and receiving information to other devices, including networked devices and networked storage systems. Typically, a physical adapter port is virtualized so that multiple instances of the physical adapter can be used for input/output operations. Each virtual instance may need a virtual adapter driver.
Typically, the physical adapter is automatically detected by a computing system that has access to a plug-n-play (PNP) functionality. The PNP functionality detects the adapter and installs the associated physical adapter driver. The virtual drivers however have to be manually installed. This approach has various shortcomings. For example, if one stops using the physical adapter or removes the physical adapter, the virtual drivers may still be present and cause unnecessary interference with other operations of the computing system. If the virtual configuration is changed, one has to manually update the associated virtual driver. Continuous efforts are being made to improve usage of computing system resources including adapter use.
SUMMARY
The various embodiments of the present system and methods for inter-driver communication have several features, no single one of which is solely responsible for their desirable attributes. Without limiting the scope of the present embodiments as expressed by the claims that follow, their more prominent features now will be discussed briefly. After considering this discussion, and particularly after reading the section entitled “Detailed Description” one will understand how the features of the present embodiments provide advantages, which include reducing the likelihood of conflicts between two drivers sharing a particular hardware resource.
In one embodiment, a machine-implemented method for managing a virtual adapter instance associated with a physical adapter is provided. The method comprises: configuring a monitoring module for detecting change in configuration of the virtual adapter instance; detecting if the configuration a has changed for the virtual adapter instance, at any given time; comparing a changed configuration with a previous configuration of the virtual adapter instance; installing a new virtual adapter instance, if new information is present in the changed configuration; and uninstalling the virtual adapter instance, if information from the previous configuration was removed.
In another embodiment, machine readable storage medium storing executable instructions, which when executed by a machine, causes the machine to perform a process for managing a virtual adapter instance associated with a physical adapter is provided. The process comprises: configuring a monitoring module for detecting change in configuration of the virtual adapter instance; detecting if the configuration has changed for the virtual adapter instance, at any given time; comparing a changed configuration with a previous configuration of the virtual adapter instance; installing a new virtual adapter instance, if new information is present in the changed configuration; and uninstalling the virtual adapter instance, if information from the previous configuration was removed.
In yet another embodiment a computer program product is provided. The computer program product, comprises: a computer usable storage medium having computer readable instructions embodied therein for managing a virtual adapter instance. The computer readable instructions include instructions for configuring a monitoring module for detecting change in configuration of the virtual adapter instance, instructions for detecting if the configuration has changed for the virtual adapter instance, at any given time; instructions for comparing a changed configuration with a previous configuration of the virtual adapter instance; instructions for installing a new virtual adapter instance, if new information is present in the changed configuration; and instructions for uninstalling the virtual adapter instance, if information from the previous configuration was removed.
This brief summary has been provided so that the nature of the disclosure may be understood quickly. A more complete understanding of the disclosure can be obtained by reference to the following detailed description of the preferred embodiments thereof concerning the attached drawings
BRIEF DESCRIPTION OF THE DRAWINGS
The various embodiments of the present system and methods for inter-driver communication now will be discussed in detail with an emphasis on highlighting the advantageous features. These embodiments depict the novel and non-obvious system and methods shown in the accompanying drawings, which are for illustrative purposes only. These drawings include the following figures, in which like numerals indicate like parts:
FIG. 1A is a block diagram of the internal functional architecture of a typical host system;
FIG. 1B shows an example of virtual adapter configuration that is used by the various embodiments disclosed herein;
FIG. 1C shows an example of a system using a legacy plug-n-play module;
FIG. 1D shows an architecture of a system, according to one embodiment;
FIG. 1E shows an example of a device registry, used according to one embodiment; and
FIGS. 2-4 show various process flow diagrams, according to one embodiment.
DETAILED DESCRIPTION
The following detailed description describes the present embodiments with reference to the drawings. In the drawings, reference numbers label elements of the present embodiments. These reference numbers are reproduced below in connection with the discussion of the corresponding drawing features.
As a preliminary note, any of the embodiments described with reference to the figures may be implemented using software, firmware, hardware (e.g., fixed logic circuitry), manual processing, or a combination of these implementations. The terms “logic,” “module,” “component,” “system” and “functionality,” as used herein, generally represent software, firmware, hardware, or a combination of these elements. For instance, in the case of software implementation, the terms “logic,” “module,” “component.” “system,” and “functionality” represent program code that performs specified tasks when executed on a processing device of devices (e.g., CPU or CPUs). The program code can be stored in one or more computer readable memory devices.
More generally, the illustrated separation of logic, modules, components, systems, and functionality into distinct units may reflect an actual physical grouping and allocation of software, firmware, and/or hardware, or can correspond to a conceptual allocation of different tasks performed by a single software program, firmware program, and/or hardware unit. The illustrated logic, modules, components, systems, and functionality may be located at a single site (e.g., as implemented by a processing device), or may be distributed over a plurality of locations.
The term “machine-readable media” and the like refers to any kind of medium for retaining information in any form, including various kinds of non-transitory storage devices (magnetic, optical, static, etc.). Machine-readable media also encompasses transitory forms for representing information, including various hardwired and/or wireless links for transmitting the information from one point to another.
The embodiments disclosed herein, may be implemented as a computer process (method), a computing system, or as au article of manufacture, such as a computer program product or computer-readable media. The computer program product may be computer storage media, readable by a computer device, and encoding a computer program of instructions for executing a computer process. The computer program product may also be a propagated signal on a carrier, readable by a computing system, and encoding a computer program of instructions for executing a compute process.
FIG. 1A is a high-level block diagram showing an example of the architecture of a processing system 100 , at a high level, in which the processes described herein, can be implemented. Note that certain standard and well-known components, which are not germane to the present invention, are not shown in FIG. 1A .
The processing system 100 includes one or more processor 104 (shown as 104 a - 104 n ) and memory 106 , coupled to a bus system 108 . The bus system 108 is an abstraction that represents any one or more separate physical buses and/or point-to-point connections, connected by appropriate bridges, adapters and/or controllers. The bus system 108 , therefore, may include, for example, a system bus, a Peripheral Component Interconnect (PCI) bus, a HyperTransport or industry standard architecture (ISA) bus, a SCSI bus, a universal serial bus (USB), or an Institute of Electrical and Electronics Engineers (IEEE) standard 1394 bus (sometimes referred to as “Firewire”).
Processor 104 is the central processing unit (CPUs) of the processing system 100 and, thus, controls its overall operation. In certain embodiments, the processor 104 accomplishes this by executing programmable instructions stored in memory 106 . A processor 104 may be, or may include, one or more programmable general-purpose or special-purpose microprocessors, digital signal processors (DSPs), programmable controllers, application specific integrated circuits (ASICs), programmable logic devices (PLDs), or the like, or a combination of stick devices.
Memory 106 represents any form of random access memory (RAM), read-only memory (ROM), flash memory, or the like, or a combination of such devices. Memory 106 includes the main memory of the processing system 100 . ROM stores invariant instruction sequences, such as start-up instruction sequences or basic input/output operating system (BIOS) sequences for operation of a keyboard (not shown).
Also connected to processor 104 through the bus system 108 are one or more internal mass storage devices 109 , an adapter interface 110 and other devices and interface 111 . The other devices and interface 111 may include a display device interface, a keyboard interface, and a pointing device interface.
Internal mass storage devices 109 (also referred to as storage 109 ) may be, or may include any conventional medium for storing data in a non-volatile manner, such as one or more magnetic or optical based disks, flash memory devices. CD-ROMs and others. Storage 109 stores operating system program files, application program files, and other instructions. Some of these files are stored on storage 109 using an installation program. For example, processor 104 may execute computer-executable process steps of an installation program so that the processor 104 can properly execute the application program.
Adapter 114 may include a host interface 116 , network module 122 , storage module 120 , adapter processor 124 , memory 126 , a direct memory access (DMA) module 118 and at least one physical port 128 . The host interface 116 is configured to interface with the host system 102 , via interconnect 112 . As an example, interconnect 112 may be a PCI, PCI-X, PCI-Express or any other type of interconnect.
Memory 126 may be used to store programmable instructions, for example, firmware. The adapter processor 124 executes firmware stored in the memory 126 to control overall functionality of adapter 114 .
DMA module 118 manages requests for link 112 . The requests may come from network module 112 , storage module 120 or any other components for sending or receiving information.
Port 128 may send information to and receive information from other devices via link 130 . Port 128 includes logic and circuitry to handle network information. The nature and structure of the logic will depend on the protocol/standard that is used for handling the information. For example, if Fibre Channel, Ethernet, or other protocols are used, then port 128 includes the logic and circuitry to handle protocol specific communication. The adaptive embodiments disclosed herein are not limited to any particular protocol or standard.
In one embodiment, adapter 114 may be configured to handle both network and storage communication using network module 122 and the storage module 120 that are coupled to port 128 . Various network and storage protocols may be used to handle network and storage traffic. Some common protocols are described below.
One common network protocol is Ethernet. The original Ethernet bus or star topology was developed for local area networks (LAN) to transfer data at 10 Mbps (mega bits per second). Newer Ethernet standards (for example, Fast Ethernet (100 Base-T) and Gigabit Ethernet) support data transfer rates between 100 Mbps and 10 gigabit (Gb). The description of the various embodiments described herein is based on using Ethernet (which includes 100 Base-T and/or Gigabit Ethernet) as the network protocol. However, the adaptive embodiments disclosed herein are not limited to any particular protocol, as long as the functional goals are met by an existing or new network protocol.
One common storage protocol used to access storage systems is Fibre Channel. Fibre channel is a set of American National Standards Institute (ANSI) standards that provide a serial transmission protocol for storage and network protocols such as HIPPI, SCSI, IP, ATM and others. Fibre channel supports three different topologies: point-to-point, arbitrated loop and fabric. The point-to-point topology attaches two devices directly. The arbitrated loop topology attaches devices in a loop. The fabric topology attaches host systems directly (via HBAs) to a fabric, which are then connected to multiple devices. The Fibre Channel fabric topology allows several media types to be interconnected. Fibre Channel fabric devices include a node port or “N_Port” that manages Fabric connections. The N_port establishes a connection to a Fabric element (e.g., a switch) having a fabric port or F_port.
A new and upcoming standard, called Fibre Channel over Ethernet (FCOE) has been developed to handle both Ethernet and Fibre Channel traffic in a SAN. This functionality would allow Fibre Channel to leverage 10 Gigabit Ethernet networks while preserving in the Fibre Channel protocol.
In an exemplary implementation, adapter 114 may be similar to a converged network adapter available from Qlogic Corporation.
Adapter 114 may be virtualized and shared among different processors, components and systems. The term “virtual” as used herein means a logical image or instance of the physical adapter. More than one virtual instance may be used so that different resources are able to share one physical adapter. Each virtual instance may operate as an independent entity.
FIG. 1B shows an example of virtualizing adapter 114 . The virtualizing adapter 114 includes a configuration 132 and a physical address 134 . A first virtual instance for adapter 114 is shown as virtual adapter 1 136 . Virtual adapter 1 136 has a virtual identifier 138 and virtual configuration 140 . The virtual identifier in this example may be NPIV, an N_Port virtual identification scheme provided by the Fibre Channel standards. In this scheme, port 128 has a unique worldwide port number (WWPN) that is provided by an adapter provider, for example, QLogic Corp. Virtual identifiers (NPIV IDs) may be used to provide unique virtual identifiers for port 128 . This allows one to virtualize physical adapter 114 as a virtual adapter 1 136 . Virtual adapter 1 136 operates as an independent entity that may be used by a processor, an independent host system or any other component/module.
Similar to virtual adapter 136 , various other virtual adapters ( 142 , 148 ) using different virtual identifiers ( 144 , 150 ) having different virtual configurations ( 146 , 152 ) may be used by different components, including different host systems.
FIG. 1C shows a top-level block diagram of a system 155 used for net communication. System 155 includes an operating system 154 that is executed by processor 104 out of memory 106 , according to one embodiment. Processor 104 may execute application module 156 to generate input/output requests. In one embodiment, application module 56 may issue I/O requests for reading and writing information stored at other devices, for example, storage devices. Application 156 may send an I/O request to adapter driver 166 that in interfaces with adapter firmware 168 , executed by adapter processor 124 . Based on the request, information is either received or sent to host system 102 .
When adapter 114 is virtualized, processor 104 executes virtual port drivers 158 , 160 . Virtual drivers 158 and 160 are mapped to physical adapter driver 166 .
In conventional systems, a plug-n-play (PNP) module 164 is used for recognizing adapter 114 . PNP in this context means that when adapter 114 is plugged into a slot (for example, a PCI, PCI-X, PCI-Express slot), the PNP module 164 immediately recognizes the hardware and loads adapter driver 166 , if one is not available.
The legacy PNP module 162 is used for installing virtual port drivers 158 , 160 . Under the legacy PNP module 162 , one has to manually install a virtual driver. One reason for doing that is because a virtual instance of the adapter may be configured by the user without inserting/re-inserting the physical adapter.
The use of legacy PNP module 162 has shortcomings. For example, whenever adapter driver 166 is removed, virtual drivers 158 and 160 may still linger on and may even attempt to restart after a reboot operation. To solve this problem, one will have to manually remove the virtual drivers after the physical adapter or driver is removed/modified. Another problem the conventional systems is that if there is a change in configuration of a virtual or physical driver, one has to manually update all the virtual drivers.
The various embodiments disclosed herein alleviate the problems associated with virtual adapters/drivers. A virtual port driver manager module is provided that automates virtual adapter driver installation, monitors driver/adapter configurations and updates the virtual drivers.
FIG. 1D shows an example of a virtual port driver manager 170 (may be referred to as manager 170 ) that handles the various functions associated with virtual adapters and drivers, as described below. Manager 170 is installed when adapter 114 is being installed and configured. During adapter 114 configuration, a virtual PNP service 165 is also installed. The virtual PNP service 165 is used to register and create a PNP thread 151 (may also be referred to as a virtual PNP thread) with operating system 154 . Virtual PNP thread 151 monitors virtual adapters and virtual adapter configurations.
A physical adapter thread 149 (shown as adapter thread 149 ) is also created and registered with operating system 154 . Adapter thread 149 is used to monitor changes in adapter 114 configuration, including when adapter 114 is removed.
Device registry 153 is maintained by operating system 154 to store information regarding adapter 114 . This information may be received from a management application that is used to manage a storage area network (not shown), FIG. 1E shows the type of information that may be stored with respect to adapter 114 . For example, registry 153 may include a virtual adapter identifier 153 A. This identifier identities a virtual adapter instance (for example, 136 , FIG. 1B ). In one embodiment, NPIV may be used to identify the virtual adapter instance.
Device registry 153 may also include worldwide port names (WWPNs) 153 B having two sub-components 153 C and 153 D, 153 C may be used to identify the adapter 114 as a network node and 153 D may be used to identify a physical port of adapter 114 , for example, port 128 ( FIG. 1A ). The WWPNs are typically provided by the adapter 114 provider. For example, QLogic Corporation, a supplier of adapter 114 may provide the WWPNs via a special utility that will generate the WWPNs for the NPIV port for use to attach to the physical adapter port identified by the corresponding WWPN.
Registry 153 also stores the virtual port numbers 153 E associated with a physical port. In one embodiment. NPIV may be used to provide a virtual identifier 153 E to a physical port. Registry 153 may include other fields 153 F that may not be germane to the inventive embodiments disclosed herein.
Referring back to FIG. 1D , Manager 170 manages installation and removal of virtual drivers 158 , 160 as virtual adapter configurations are created, modified, updated or removed without having to use the legacy PNP modules 162 ( FIG. 1C ). One does not need a legacy PNP module 1162 because virtual port driver manager 170 automates handling of virtual adapters/drivers, as described below.
Manager 170 interfacing with operating system 154 installs a virtual adapter instance when a user creates a new virtual adapter configuration. When a configuration is removed, manager 170 removes the configuration and the associated virtual adapter drivers. When a virtual adapter is modified, manager 170 may remove the virtual instance and reinstall a modified version. Manager 170 installs all associated virtual adapters when the physical adapter is installed and initialized. The virtual adapters are removed when the physical adapter is uninstalled.
In one embodiment, manager 170 includes programmable instructions that are executed by processor 104 for performing the various functions described above. The instructions may be executed out a memory (for example, 106 ). The functionality of manager 170 is now described below with respect to the process flow diagrams of FIGS. 2-4 .
FIG. 2 shows a top-level process flow diagram for installing and configuring adapter 114 . Adapter 114 is installed in block S 200 . In one embodiment, adapter 114 is installed in a PCI-Express slot (not shown). The adaptive embodiments however are not limited to any particular type of slot.
In block S 202 , manager 170 is also installed with adapter driver 166 FIG. 1D ). The virtual PNP service 165 is initialized in block S 204 . The PNP service allows one to configure adapter 114 , which is initialized in block S 206 .
During adapter configuration, all adapter ports (for example, 128 , FIG. 1A ) are enumerated and configured in block S 208 . In block S 210 , virtual PNP thread 151 is created and registered with operating system 154 . The virtual PNP thread 151 is used to monitor all virtual adapter instances and configurations.
In block S 212 , adapter 114 is registered with operating system 154 . Thereafter, in block S 214 , an adapter monitoring thread 149 is created.
The term “thread” as used herein means executable instructions that are programmed for performing a particular task. For example, the PNP thread is used to create, monitor and remove the virtual adapter instances and configurations, while the adapter thread monitors the physical adapter configuration and changes associated therewith, meaning each associated virtual configuration.
FIG. 3 is a process flow diagram for executing the virtual PNP thread 151 , according to one embodiment. The process begins in block S 300 and in block S 302 , manager 170 determines if adapter configuration is present. If the configuration information is present, then it is loaded in block S 304 . In one embodiment, processor 104 loads the configuration information from register 153 to memory 106 . Thereafter, manager 170 registers the events such as changes in configuration such as addition or removal of physical adapters as described in the registry or discovered by the operating system that need to be monitored by the virtual PNP thread 151 . The events are registered with operating system 154 that has visibility regarding various system 100 components in step S 306 . One such event may be to monitor change in virtual adapter configuration.
In block 5308 , virtual PNP thread 151 determines if a virtual adapter configuration has changed. Virtual PNP thread 151 may receive that information from operating system 154 that maintains virtual adapter configuration information. If the configuration did not change, the monitoring continues in block S 324 and the process ends in block S 326 .
If the configuration changed, then in block S 310 , virtual PNP thread 151 reads the configuration information from register 153 and compares it with the changed information. In another embodiment, operating system 154 may perform this step.
Based on the comparison, in block S 312 , the process determines if new configuration information is present. If yes, then a virtual adapter instance is plugged in by manager 170 using virtual PNP service 165 in step S 314 .
If no new information is present, then the process determines if information was removed in step S 320 . If information was removed, then in block S 322 , the associated virtual adapter instance is removed, and the PNP device (i.e. adapter 114 ) is uninstalled.
If the information was not removed in block S 320 , then the process determines if there is more information in step S 316 . If not, then the process exits in block S 318 , otherwise the process moves back to block S 312 .
FIG. 4 shows another process flow diagram for using the virtual PNP thread 151 and manager 170 , according to one embodiment. The process begins in block S 400 when physical adapter 114 is installed. Adapter 114 is typically inserted in an adapter slot (not shown) in host system 102 in step S 402 . In block S 404 , a user using a configuration utility or management application configures adapter 114 . The user may configure one or more virtual adapters associated with physical adapter 114 . NPIV may be used to configure the virtual adapters.
In block S 406 , a virtual adapter associated with the physical adapter 114 is configured. In block S 410 , a virtual adapter driver ( 158 , 160 ) is installed. In one embodiment, manager 170 installs the virtual adapter driver. Thereafter, the adapter 114 is used for sending and receiving information. The configuration and connections for the virtual adapters and the physical adapter are monitored in block S 412 . The various monitoring steps are shown as blocks S 414 A-S 414 D that are described below in detail.
In block S 414 A, a new virtual adapter instance is installed, if a new configuration is detected.
In block S 414 B, a virtual adapter instance is removed when a virtual configuration is removed. Manager 170 performs this function.
In block S 414 C, manager 170 reinstalls a virtual adapter instance, when in existing virtual adapter is modified.
In block S 414 D, if the physical adapter is removed, then the virtual adapter instances are also removed from the host system. Manager 170 performs this block as well.
The embodiments disclosed herein improve a user's experience in using virtual adapters. One does not have to deal with redundant virtual adapter instances, when they are not being used or needed. Also, adapter drivers and configurations are updated automatically based on a monitoring thread.
Thus, a method and apparatus for handling adapter virtualization have been described. Note that references throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Therefore, it is emphasized and should be appreciated that two or more references to “an embodiment” “one embodiment” or “an alternative embodiment” in various portions of this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics being referred to may be combined as suitable in one or more embodiments of the invention, as will be recognized by those of ordinary skill in the art.
While the present disclosure is described above with respect to what is currently considered its preferred embodiments, it is to be understood that the disclosure is not limited to that described above. To the contrary, the disclosure is intended to cover various modifications and equivalent arrangements within the spirit and scope of the appended claims. | System and method for managing a virtual adapter instance associated with a physical adapter is provided. The method includes configuring a monitoring module for detecting change in configuration of the virtual adapter instance; detecting if the configuration has changed for the virtual adapter instance, at any given time; comparing a changed configuration with a previous configuration of the virtual adapter instance; installing a new virtual adapter instance, if new information is present in the changed configuration; and uninstalling the virtual adapter instance, if information from the previous configuration was removed. | 6 |
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to fracturing subterranean formations and to fracture monitoring methods.
[0002] There are various uses for fractures created in subterranean formations. In the oil and gas industry, for example, fractures may be formed in a hydrocarbon-bearing formation to facilitate recovery of oil or gas through a well communicating with the formation.
[0003] Fractures can be formed by pumping a fracturing fluid into a well and against a selected surface of a formation intersected by the well. Pumping occurs such that a sufficient hydraulic pressure is applied against the formation to break or separate the earthen material to initiate a fracture in the formation.
[0004] A fracture typically has a narrow opening that extends laterally from the well. To prevent such opening from closing too much when the fracturing fluid pressure is relieved, the fracturing fluid typically carries a granular or particulate material, referred to as “sand” or “proppant,” into the opening of the fracture. This material remains in the fracture after the fracturing process is finished. Ideally, the proppant in the fracture holds the separated earthen walls of the formation apart to keep the fracture open and provides flow paths through which hydrocarbons from the formation can flow at increased rates relative to flow rates through the unfractured formation. In another application, acids are used to create uneven surfaces so that the fracture does not completely close, thus still providing effective flow channels through the fracture.
[0005] Such a fracturing process is intended to stimulate (that is, enhance) hydrocarbon production from the fractured formation. Unfortunately, this does not always happen because the fracturing process can damage rather than help the formation (for example, proppant can clog the fracture tip to produce a “screenout” condition).
[0006] Stimulating wells that behave nicely (for example, wells that are easily stimulated) allows service companies and operators to follow standard procedures commonly performed on such wells. No special attention needs to be placed upon specifics, such as how the fracture behaves; decisions and actions are based upon the experience the industry has acquired over many years.
[0007] However, as the hydrocarbon supply decreases and demand for it increases, the hunt for hydrocarbons becomes more challenging. New technologies, such as fluid chemistry and rheology, or even new stimulation techniques enter the marketplace. These techniques claim to provide better fracture creation, better conductivities, permeability modifications, and more. As these technologies are used, new methods for evaluating the effectiveness of the treatments are needed.
[0008] In at least these more challenging situations, fracture behavior is an important aspect in fracturing technology. Many techniques are available for pre-stimulation simulations and post-stimulation analyses of fracture behavior; however, few techniques address fracture behavior during the stimulation process itself. Various fracture behaviors, such as fracture extension, ballooning, and tip screenout are often not known to the operator until after it is too late or even after the job is completed. Therefore, there is a need for real-time analysis or monitoring of fractures.
SUMMARY OF THE INVENTION
[0009] The present invention meets the aforementioned need by providing a novel and improved fracture monitoring method and fracturing method.
[0010] Certain changes occurring downhole during a fracturing process, such as fracture extension, send different pressure frequency spectra and wave intensities to the surface. In accordance with the present invention, these signals can be processed to reveal information about one or more aspects of the downhole environment. That is, capturing and evaluating generated and reflected pressure waves during fracturing enables personnel to monitor, in real time or later, what happens downhole during fracturing.
[0011] Any time a fracture extends, there is a sudden burst of acoustic noise embodied in a pressure wave or signal. Noise coming from other sources also contributes to this signal. By converting the time based pressure signal to a frequency base using a Fourier transform, for example, one can monitor this acoustic noise. In a particular implementation of the present invention, this is implemented with a waterfall plot of frequency spectra at successive time slices of the original signal. In such a waterfall plot, and in accordance with the present invention, a ridge of decreasing frequencies indicates fracture extension and a ridge of increasing frequencies indicates either closure or sand/proppant backing up in the fracture. By summing the area under the spectral plot, one can also get an indication of the energy drop as the fracture extends and sudden rise at a screen out.
[0012] A fracture monitoring method in accordance with the present invention comprises: creating frequency spectrum data in response to a pressure in a well sensed over time during a fracturing process performed on the well; and determining from the frequency spectrum data at least one characteristic of a fracture formed by the fracturing process. This can include one or more of the following, for example: determining, in response to a declining frequency defined in the frequency spectrum data, that the fracture is being extended by the fracturing process; determining, in response to an increasing frequency defined in the frequency spectrum data, that the fracture is effectively not being extended by the fracturing process; and determining, in response to an increasing frequency defined in the frequency spectrum, that proppant is backing up in the fracture.
[0013] In one embodiment, creating frequency spectrum data includes applying a frequency transform to data of the sensed pressure. Examples of frequency transform include a Fourier Transform in general and a Short Time Fourier Transform in particular.
[0014] Creating frequency spectrum data can also include filtering data of the sensed pressure. Such filtering includes wavelet filtering in one embodiment of the present invention.
[0015] A fracture monitoring method of the present invention can also be defined as comprising: sensing pressure over time during a fracturing process performed on a well such that pressure data is obtained; making a frequency analysis of the pressure data, including making a waterfall plot of frequency data obtained in response to the pressure data; and using the waterfall plot to determine at least one characteristic of a fracture formed by the fracturing process. Using the waterfall plot in one embodiment of the present invention includes identifying one or both of (1) a declining ridge section for a selected frequency range over a period of time and (2) an increasing ridge section for the selected frequency range.
[0016] The present invention can also be defined as a computer-implemented fracture monitoring method, comprising: receiving in a computer pressure data obtained over time from a well undergoing a fracturing process; performing in the computer a transform on pressure data received in the computer to provide frequency data for selected times of the pressure data; and using the frequency data to determine whether a fracture created by the fracturing process is extending, including determining decreasing and increasing frequency sections within the frequency data.
[0017] A fracturing method of the present invention broadly comprises: pumping a fracturing fluid into a well such that a fracture in an adjacent formation forms and pressure signals are generated; sensing the pressure signals; determining frequencies at various times of the sensed pressure signals; creating a plot of the frequencies at the various times; and
[0018] determining from the plot whether the fracture is extending into the formation. This can further comprise controlling further pumping of the fracturing fluid in response to determining whether the fracture is extending.
[0019] Other aspects consistent with the foregoing are included in further definitions of the present invention.
[0020] Therefore, from the foregoing, it is a general object of the present invention to provide a novel and improved fracture monitoring method and fracturing method. Other and further objects, features and advantages of the present invention will be readily apparent to those skilled in the art when the following description of the preferred embodiments is read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIG. 1A represents one type of fracturing process using a method of the present invention.
[0022] [0022]FIG. 1B represents another type of fracturing process using a method of the present invention.
[0023] [0023]FIG. 1C represents still another type of fracturing process using a method of the present invention.
[0024] [0024]FIG. 2 is a flow chart of procedures of the present invention.
[0025] [0025]FIG. 3 shows a waterfall plot for a well A in accordance with the present invention.
[0026] [0026]FIG. 4 shows another waterfall plot for well A in accordance with the present invention.
[0027] [0027]FIG. 5 shows a waterfall plot for a well B in accordance with the present invention.
[0028] [0028]FIG. 6 shows a waterfall plot for a well C in accordance with the present invention.
[0029] [0029]FIG. 7 shows a waterfall plot for well C in accordance with the present invention, including use of wavelet technology.
[0030] [0030]FIG. 8 shows another waterfall plot for well C in accordance with the present invention, including use of wavelet technology and focusing on part of the plot shown in FIG. 7.
[0031] [0031]FIG. 9 shows a view from the other side of the plot of FIG. 8.
[0032] [0032]FIG. 10 shows plots of annulus pressure and downhole proppant concentration data for a first fracture of a well D.
[0033] [0033]FIG. 11 shows a waterfall plot created from the data of FIG. 10 in accordance with the present invention.
[0034] [0034]FIG. 12 shows plots of annulus pressure and downhole proppant concentration data for a second fracture of well D.
[0035] [0035]FIG. 13 shows a waterfall plot created from the data of FIG. 12 in accordance with the present invention.
[0036] [0036]FIG. 14 shows plots of annulus pressure and downhole proppant concentration data for a third fracture of well D.
[0037] [0037]FIG. 15 shows a waterfall plot created from the data of FIG. 14 in accordance with the present invention.
[0038] [0038]FIG. 16 shows plots of annulus pressure and downhole proppant concentration data for a fourth fracture of well D.
[0039] [0039]FIG. 17 shows a waterfall plot created from the data of FIG. 16 in accordance with the present invention.
[0040] [0040]FIG. 18 shows plots of annulus pressure and downhole proppant concentration data for a fifth fracture of well D.
[0041] [0041]FIG. 19 shows a waterfall plot created from the data of FIG. 18 in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0042] A fracturing process using a method of the present invention is represented in FIG. 1A. This includes pumping a fracturing fluid 2 into a well 4 such that a fracture 6 in an adjacent formation 8 forms and pressure signals are generated. The fracturing fluid 2 can be of any suitable type known in the art, and it is pumped into the well 4 in any suitable manner known in the art. In FIG. 1A, the placement of the fracturing fluid is shown as occurring through a tubing string 10 that extends into a region of the well 4 that is isolated in known manner by suitable known sealing devices 12 , 14 (for example, packers). This isolated region enables the fracturing fluid 2 to be exerted against the desired portion of the formation 8 and thereby initiate and extend the fracture 6 (only one wing of which fracture is shown in that a fracture typically extends in two (typically opposite) directions from the wellbore).
[0043] The present invention is not limited to any particular fracturing fluid or fracturing fluid placement technique; therefore, other fracturing fluid and delivery can be used. One non-limiting example is of the type represented in FIG. 1B; here, fracturing fluid is pumped through tubing string 10 outside an inner tubing string 10 a (in the FIG. 1B application, tubing string 10 a can be referred to as a “deadstring”) disposed within the tubing string 10 . In the FIG. 1B representation, pressure is sensed through the deadstring. Another non-limiting example is hydrajet fracturing technology, with which fractures can be placed in cased or open vertical, deviated or horizontal well sections without the use of sealing devices such as packers and bridge plugs. In this process, represented in FIG. 1C, a dual-flow system is used in which both outer tubing string 10 and inner tubing string 10 a deliver fracturing fluid through a hydrajet tool, which can also function as a perforating tool (when the hole is cased or lined) and as a sealing device using the Bernoulli principle. The sealing provided is a dynamic sealing process achieved by fluid velocity. This velocity, which is created through the jetting tool, propels fluid at velocities greater than 650 feet/second. Therefore, according to Bernoulli, pressures around the jet are quite low. Depending on local conditions, annular fluid may enter the high-velocity fluid stream into the fracture, or, because the sealing is not absolute, the jet fluid may leak off into the annulus.
[0044] The fracturing method of the present invention, with whatever fracturing fluid and delivery that may be selected, further comprises sensing pressure signals that arise during the pumping of the fracturing fluid and resultant fracture creation. Sensing of pressure can occur using any suitable technique. For example, sensing can occur downhole with real-time data telemetry to the surface or delayed transfer (for example, by data storage downhole and retrieval of the downhole sensing device or by data storage downhole and later telemetry to the surface). Such downhole sensing can be in any suitable location typically selected dependent on the specific fracturing fluid placement technique used (for example, in the tubing string (see, for example, FIG. 1A); in the isolated region (see, for example, FIG. 1B); or in the annulus if it communicates with the pressure (see, for example, FIG. 1C). Alternatively or additionally, sensing can occur at the surface. Consider, for example, that the fluid delivery system is typically the largest supplier of sound/pressure waves inside the wellbore. These pressure waves are delivered downhole by high-pressure fluids. In at least the hydrajet fracturing process, high-pressure fluid energy is transformed into high kinetic energy, and a high-frequency pressure wave is mixed into this accumulation of sound energy. In conventional fracturing technologies, these pressure/sound waves are transmitted through the treating string, but in the hydrajet fracturing approach, the annulus may serve as the better transmission conduit. In other jobs, downhole gauge readings may provide the better data to evaluate. In general, however, any sensing technique and equipment suitable for detecting the desired pressure signal(s) with adequate sensitivity/resolution can be used. Whatever pressure sensing is used, the pressure signal is provided to the surface, typically in the form of an electrical signal, as indicated by reference numeral 16 in FIG. 1.
[0045] It is known that the pressure to be sensed can change over time and that the pressure can include pressure components of various frequencies. Certain of these frequencies might be amplified by certain shape factors and dimensions of the well cavity and the fracture. For example, as the fracture 6 of the FIG. 1 illustrations grows, dominating frequencies within the composite pressure may change during the fracturing process. As a fracture develops, typically certain frequency components are amplified and the complex mixture of pressure/sound waves is transmitted back to the surface. Thus, in accordance with the present invention, the fracturing method being described with reference to the FIG. 1 illustrations also comprises, as indicated at reference numeral 18 , determining frequencies at various times of the sensed pressure signals and determining from such data at least one characteristic of the fracture 6 formed by the fracturing process. This can be performed, at least in part, using a suitable computer 20 that provides an output signal to be used to control the overall fracturing process, such as controlling the pumping of the fracturing fluid or the formulating of the fracturing fluid, for example. An example of such a computer 20 includes types of conventional data acquisition systems used at well sites in the oil and gas industry as known in the art, but programmed (in software or firmware) using known programming techniques to implement the desired functions of the present invention as described herein. In accordance with the present invention, fracture behavior, including positioning of sand or proppants, can be used by such computer 20 to determine whether or not to increase flow rate or decrease proppant flow when the fracture is trying to close or screening out prematurely, or to decrease flow rate or increase proppant flow when screenout is desired.
[0046] In using the computer 20 , for example, in accordance with the present invention, the computer 20 receives pressure data obtained over time from the well undergoing the fracturing process (well 4 in the illustrations of FIG. 1). Receiving such pressure data is indicated in FIG. 2 by reference numeral 22 . Using the present invention, such data is transformed to frequency data at selected sampling times related to the time aspect of the pressure data; this is indicated in FIG. 2 by the reference numeral 24 . From the frequency data, frequency related changes over time are identified as indicated at reference numeral 26 in FIG. 2. In a particular implementation of the present invention, decreasing or increasing (“or” being inclusive as encompassing either or both) frequency sections are identified, which decreasing/increasing is used to determine one or more characteristics of the fracture as indicated by reference numeral 27 in FIG. 2.
[0047] In making a frequency analysis of the pressure data by transforming the pressure-time data into frequency data, frequency spectrum data is created in response to pressure in the well sensed over time during the fracturing process performed on the well. Many transform methods are known in the mathematical and engineering world, such as Hilbert, Wigner and Radon Transforms, and of course Fourier Transforms. Fourier transform methods are popular in the engineering world and are particularly suitable in the present invention. In a particular implementation, this includes performing in the computer 20 (for the FIG. 1 example) a Short Time Fourier Transform (STFT) on the pressure data received in the computer; this provides frequency data for selected times of the pressure data. Wavelet technology can also be used, such as by being performed before doing the transform but in a manner to focus the later applied transform and analysis on a selected frequency range.
[0048] To use the frequency data in accordance with a particular implementation of the present invention, the aforementioned increasing or decreasing sections are identified. This identification can be performed within the computer 20 , for example, such as using suitable programming to compare respective frequency spectra over the selected time slices used during the transformation from pressure to frequency data. Another identification technique includes obtaining a graphical output, such as can be provided from suitably programmed computer 20 , for example, that creates a plot of the frequencies of short bursts at the various times using the STFT approach. For example, Fourier transformation is performed on a set of data points from the pressure data at a time n to the pressure data at a time m (P n to P m ), the next one for P n+k to P m+k where k is greater than 1, etc. for the number of pressure “slices” desired. One specific type of plot is a waterfall plot, such as of a type described further below. Note that a waterfall plot helps the human mind capture the phenomenon; while computers may not need such methods to do its decision making steps.
[0049] In a particular implementation of the present invention, determining at least one characteristic of the fracture from the frequency data includes determining, in response to a declining frequency defined by the frequency spectrum data, that the fracture is being extended by the fracturing process. This can be obtained, for example, from a waterfall plot mentioned above if in such plot there is a section of declining frequency over a period of time.
[0050] Another characteristic that can be determined is related to an increasing frequency. That is, determining at least one characteristic of the fracture includes determining, in response to an increasing frequency defined by the frequency spectrum data, that the fracture is not being extended by the fracturing process. Such increasing frequency information has been specifically related both to a fracture closing and to proppant backing up in the fracture (such as in a tip screenout event). This can be obtained, for example, from a waterfall plot mentioned above if in such plot there is a section of increasing frequency over a period of time.
[0051] The foregoing has considered the present invention in the context of a fracturing method. Following is more detailed information relevant to this, as well as to specifically the fracture monitoring method portion of the present invention.
[0052] Some important aspects of a fracture stimulation process are the measured depth of the well and the fact that fractures increase the size of the contained cavity or control volume. Fracture closure decreases this volume. Additionally, the sand or proppant filling the fracture reduces the void space. However, the measured depth of the well remains the same during the stimulation process. Therefore, a natural frequency component related to the well depth is defined by the following equation:
F=c /(2× MD )
[0053] where F is frequency, c is the speed of sound in the fluid in the well, and MD is measured depth.
[0054] Data exhibiting frequencies lower than the one calculated in accordance with the above equation is taken as coming from inside the fracture because a frequency lower than the measured distance-related natural frequency indicates a larger distance than the measured depth of the well. On the other hand, frequencies higher than the natural frequency associated with the measured depth could be random noise or noise reflected from inside the fracture to the wellbore wall (that is, a distance shorter than the measured depth). Fracture growth or closure or packing of sand is a continuous process during which changing pressures occur downhole. The present invention obtains frequencies from such pressures using numerous transformed data sets, such as in a particular implementation using several Fourier charts created as a function of time. In accordance with the present invention, such stacked charts, or waterfall plots, quickly illustrate trends or movements in the fracture, allowing them to be identified quickly.
[0055] To facilitate the transform analysis, suitable filtering can be used to focus on selected, significant frequency ranges, for example. Wavelet technology, for example, can be used. Particularly suitable applications, but not limiting ones, include when pressure data is too complex, too noisy, or continually changing with time. Wavelets have been used in geological studies in which sound traveling through complex structures is evaluated differently from the present invention to determine the actual shape, construction, and composition of the formation. Pressure transients from a wellbore have also been evaluated differently from the present invention by using wavelet technology. In the present invention, it is contemplated that wavelets can allow closer investigation into a suspected data set or can validate a supposition created using the aforementioned Fourier analysis of the present invention, for example.
EXAMPLE 1
[0056] Well A was a vertical well that was proppant stimulated through the annulus. This well was about 8,408 feet deep (measured depth/true vertical depth).
[0057] Using the speed of sound through diesel fluid at about 3,800 feet/second and the equation set forth above, the natural frequency at the wellbore is approximately 0.226 Hz (F=3,800/(2×8,408)). FIG. 3 shows the waterfall plot of the Fourier transform charts obtained using pressure data for well A sensed through the annulus for an arrangement as in FIG. 1B. Each chart section of FIG. 3 was computed with a 16-second interval between each waterfall element. That is, each curve in the drawing represents one STFT chart of a time slot in time. The wellbore depth/length (natural) frequency component is shown as a straight dotted line 28 in FIG. 3. In this waterfall plot, locations are identified where a certain frequency amplitude exceeds a certain threshold; and the frequency movement or trend is then tracked as time progresses. Note that in the Fourier plot, amplitudes (or energy level) of lower frequency signals are greater than for higher frequencies. This is due to the fact that fluids in the wellbore tend to dampen or filter out high frequencies quickly. In the plot, we define points where frequency energy level begins to be noticeable as a “frequency front” or “wave front”. With a short time interval, trends can be easily identified. In FIG. 3, these trends are represented by a solid line 30 that follows the frequency front. Identification of these trends may sometimes be difficult, and faster data-collection rates may be necessary. In many fracturing jobs, pressure data is obtained at one data set per second. Considering the natural frequency equation given above and sampling rate, frequency detection limitations, even faster sampling may be needed in shallow wells (such as wells less than 3,800 feet deep for a speed of sound in fluid factor of 3,800 feet/second).
[0058] Fracture extension or growth (increased true cavity depth) on the plot of FIG. 3 (and subsequently illustrated waterfall plots) is defined as frequency reductions, while closure or proppant front progression to the wellbore (decreased true cavity depth) is defined by frequency increase. The solid line 30 in FIG. 3 follows these variations and indicates that fracture development occurs after the 500-second point. For example, line segment 30 a read against the frequency scale indicates a decrease from above 0.226 Hz to about 0.12 Hz, so there is fracture extension during the corresponding time; and line segment 30 b read against the frequency scale indicates an increase back to about 0.226 Hz, so there is fracture closure or proppant buildup during the corresponding time. The substantially unchanging frequency segment of line 30 between segments 30 a and 30 b indicates unchanging boundaries (for example, the fracture is not extending, or it is extending but sand is building up at the same velocity so that the boundary appears to be not extending). Additionally, a few minor closures or minor screenouts occur throughout the job. The pressure data used for FIG. 3 was the annulus pressure data.
[0059] Well A also had open production tubing (as at tubing string 10 a in FIG. 1B) through which bottomhole data was recorded. Because the fluid column did not change, downhole pressure could be recorded accurately. Obtaining the Fourier transform plots (every 16 seconds) on this data set results in the plot shown in FIG. 4. The resulting plot is much cleaner and noise effects are minimized as pressure pulses from the pumps, for example, have to travel a long distance from surface to downhole. The frequency trend is presented as a solid line 32 in this chart. The generation of the microfracture at the beginning of the job is also quite apparent in FIG. 4. Note that FIG. 4 is similar to FIG. 3 with the exception that the data is much cleaner. As each wave front depends largely upon the identifiable threshold, the Fourier wave front represented by lines 30 , 32 seems only to indicate the fracture creation qualitatively. Note that this threshold can easily be changed by using different amplification schemes; so that the absolute value is definitely suspect as to quantitatively measuring a downhole feature or condition.
EXAMPLE 2
[0060] Well B was a vertical well with depth of 6,952 feet and treated using the same manner and same installation as Well A. During this time, the recording equipment was placed in the dead string (tubing) while fracturing was done through the annulus. The stimulation treatment was performed so that a screenout would occur at the end of the job to improve fracture conductivity.
[0061] The STFT stacked chart or waterfall plot obtained as part of the present invention is shown in FIG. 5. The natural frequency related to the wellbore depth and a sound speed of 3,800 feet/second as above can be computed as 0.273 Hz, as illustrated with the dotted line 34 . Note that the sound speed changes from fluid to fluid and also is very dependent upon pressure and compressibility. Additionally, the extending of the fracture is clearly represented by this plot (see frequency front; as frequencies get lower), as is a massive screenout at the end of the job (frequency suddenly gets higher prior to the end of the job, significantly exceeding the 0.273 Hz line 34 , as indicated by reference number 35 ).
[0062] As seen in FIGS. 3 through 5, the plots are quite straightforward in conventional fracturing technologies. With “conventional fracturing” it assumes that, as in FIGS. 1A and 1B, a single stream of fluid is pumped in a tubing (typically the production tubing, for example) which is open ended within the wellbore or pumped straight into the wellbore when the tubing does not exist or if no packer assemblies are installed at the end of the production tubing. An “unconventional” or “new” fracturing technique is discussed in the next paragraph. Although the plots are still qualitative in nature, they are relatively clean from other noises. In another example discussed below, jetting energy contributes a tremendous amount of noise, thus making evaluation more difficult.
[0063] A relatively new fracturing technique, known as hydrajet fracturing (for example, one such technique is provided by Halliburton Energy Services under the mark “SurgiFrac”), employs two different flow streams, one through the tubing and the other through the annulus as represented in FIG. 1C. The inner tubing flow stream is pumped at tremendously high pressures and high flow rates (high horsepower) through jetting equipment; while the annulus flow stream between the inner and outer tubing strings is pumped at lower pressures and lower horsepower. Each of these fluid streams contributes to the noise in the system. As there is a high pressure differential across the hydrajet tool jet nozzles, fluid is accelerated to a very high velocity (up to 600-700 feet/second) which causes tremendous shearing action between the jet and the wellbore fluid; this creates tremendously high levels of noise in the system. In addition to this, the jet impacting on the wellbore walls substantially increases the noise levels, which can mask other noise components which may be needed to analyze using the present invention. Unlike conventional techniques, this new technique also generates multiple fractures at many locations in the well, and each of these fractures contributes some noise components which may affect analytical capabilities. Following are two examples of the present invention as later applied to data from two hydrajet fracture jobs.
EXAMPLE 3
[0064] Well C was slightly deviated and had a measured depth of about 10,300 feet. Lease crude was used as the primary treatment fluid.
[0065] Using a speed of sound of approximately 4,000 feet/second, a wellbore natural frequency of about 0.2 Hz is obtained. The fracture development can be observed in the Fourier transform chart in FIG. 6, which was created based on the previously obtained pressure data for Well C.
[0066] As busy as FIG. 6 is, confirming what actually happened may be done as shown by the line representing the frequency or wave front as done earlier. However, throughout the plot, there are occasionally high level bursts of noise which seems like white noise (having all frequencies present). To investigate further, wavelets are used. Using wavelet technology, the input signal (here, the pressure data) is decomposed into two sectors, which decomposition occurs in known manner to effectively filter using a selected wavelet function high/low pass filter. Each of these sectors are further decomposed into two sectors. After a few levels of such decompositions, sectors become sufficiently narrow or focused as to their frequency ranges; and for this application, a stacked plot using wavelets that were derived around the 0.2 Hz sector is shown in FIG. 7 Note that, as discussed earlier, the wellbore natural frequency is about 0.2. By selecting the area around 0.2, noise elements with frequencies around 0.2 are amplified while the others are impeded to essentially zero. Essentially, frequencies away from the wellbore basic frequencies are eliminated or filtered by use of wavelet technology to improve clarity as fractures extend from the wellbore. Known wavelet filters include gaussian, mexican hat, morlets, daubechies, and many more forms well known in the art, and the present invention is not limited to any particular wavelet filter. Using this filtering the effects of the high level, lower frequencies, are drastically reduced; and frequencies of interest (such as the frequency front discussed earlier) are now represented by frequency peaks. From the frequency peaks, we can identify slow movements of these peaks in the stacked plots and these moving peaks can be seen as ridges. Using these ridges can give better quantitative definition to the selected results (quantitatively as to relationship to frequency in the plot and possibly as to quantitative analysis or information that can be derived therefrom). In FIG. 7, the tremendous amount of “stray” noise coming from turbulence, etc., causes a flurry of peaks which makes the selection of the “real” ridge difficult. However, concentrating on ridges that originate from the 0.2 area (which is the wellbore surface) the fracture development is clearly demonstrated by arrow 36 , until the perturbation by an experiment that had been performed on the well (two successive reductions of annular flow rate by 1.5 barrels/minute each). Arrow 36 marks a declining ridge of the waterfall plot, thereby indicating fracture growth; arrow 38 marks an increasing ridge, thereby indicating screenout due to the experiment; and arrow 40 indicates a subsequent fracture growth period, when annular flow rate had been restored.
[0067] An interesting phenomenon exists during the “flow perturbation” experiment. To show this more clearly, a stacked wavelet plot was created and focused around the time the flow perturbations were made (that is, a portion of the plot of slices shown in FIG. 7 was focused on). Again, frequencies away from the wellbore basic frequencies are eliminated or filtered. This plot is shown in FIGS. 8 and 9 (which have their own time references, thus marked differently than in FIG. 7). FIG. 8 shows the plot region indicating that the fracture starts to close, while FIG. 9 shows the other side of this plot as screenout is in progress. The high peaks in these plots form an almost straight ridge on the left side of FIG. 8 and on the right side of FIG. 9, which is observed from the other side of FIG. 8. The other peak also forms a straight ridge; and this ridge is quite straight, centering and staying stationary at 0.2 (thus probably reflecting from the wellbore fracture entry correlated to our earlier mentioned wellbore function; note that this stationary behavior at 0.2 can be better seen from FIG. 9). The ridge formed by the high peaks moves slowly toward the lower frequency. In FIG. 8, an apparent ridge connects to the tall ridge on the left, which probably relates to the fracture extension. This is indicated by arrow 42 a . At the time corresponding with the end of the arrow 42 a , the flow rate was reduced by 1.5 barrels per minute (BPM) and suddenly, the ridge stayed stationary if not slightly moving to a higher frequency. It can be theorized that the fracture is extending a little, but counteracted by sand packing (front distance remains the same). When the flow is again reduced by 1.5 BPM, the frequency peak suddenly increases rapidly, even exceeding the 0.2 frequency. This indicates sudden closure of the fracture combined with sand screenout rapidly moving in the direction of the wellbore, and some of the sand, after a few seconds, starts to “populate” the wellbore. This is indicated by arrow 42 b in FIGS. 8 and 9. The flow rate was again increased, and immediately the ridge moved back to below the 0.2 mark (see arrow 42 c in FIG. 9). One aspect of these two plots of FIGS. 8 and 9 is that the wellbore frequency and the fracture-tip frequency have high peaks and their values are fixed during the stoppage. As soon as sand buildup becomes significant, the frequency is replaced by a weaker front, which may indicate that the sand pack is not yet consolidated.
EXAMPLE 4
[0068] Well D was a horizontal well stimulated using hydrajet fracturing technology. The well's true vertical depth was approximately 6,500 feet with measured depth of about 8,704 feet.
[0069] A first fracturing treatment produced the annulus pressure and the downhole proppant concentration data as shown in FIG. 10. A stacked Fourier plot created later from this data of FIG. 10 for this stimulation stage is shown in FIG. 11. Solid line 44 identifies the fracture tip movement or the proppant front movement. Sharp peaks, such as at 48 , identify tremendous white noise, which often indicates something major has occurred, such as initial fracture development. In the beginning, good fracture growth is shown to have been obtained; however, as a certain fracture length was achieved, leakoff became substantial and the fracture slowly stopped growing as indicated by the graph at reference numeral 50 . The boost pressure was increased to stagnation pressure, which reopened the fracture (more white nose) as indicated at reference numeral 52 in the plot of FIG. 11. In general, a good, but not large, fracture trend occurred, shown by arrow 46 in FIG. 11.
[0070] After the first fracture was completed, the coiled tubing moved the jetting tool to a second fracture location. The annulus pressure and downhole proppant concentrations for this second fracturing are plotted in FIG. 12. In this stage, no distinct difficulties are observable in the fracture development, as indicated by the left movement of solid line 54 in FIG. 13, which figure shows a waterfall plot later developed from the data of FIG. 12. Toward the end of the stage, there seems to be a confusing situation—one curve shows more extension (see reference numeral 56 ), but the peaks 58 on the right side of the figure could also be interpreted as the continuation of the curve. In this case, a late minor screenout may have occurred at the end of the stage.
[0071] A third fracture of well D is shown in FIGS. 14 and 15, and a fourth stage of fracturing in well D is shown in FIGS. 16 and 17. In FIGS. 15 and 17, the fracture fronts are indicated to grow as planned, as observed by the solid fracture front line 62 (FIG. 15) and 66 (FIG. 17). Note again in the present invention, that fractures are taken to grow if the front line moves to the low frequency side of the wellbore natural frequency line (dotted lines 60 , 64 in FIGS. 15, 17, respectively)
[0072] [0072]FIGS. 18 and 19 relate to a fifth fracturing in well D, with FIG. 18 representing recorded pressure and proppant concentration data at the time, and FIG. 19 showing a later developed waterfall plot using the earlier data. FIG. 18 indicates that something happened during this job because proppant concentrations suddenly jump to about 12.5 pounds per gallon (lb/gal). FIG. 19 shows that screenout occurred almost instantaneously after the sudden increase of proppant concentration downhole. This is evident by the curve 68 moving rapidly to the right (no evidence of staying within the left side of the dotted line) and also the tremendous noise activities 70 at high frequencies.
[0073] From the foregoing, a particular implementation of the present invention includes using a waterfall plot to identify at least one of a declining ridge section for a selected frequency range over a period of time and an increasing ridge section for the selected frequency range. In at least some applications, using the waterfall plot includes identifying a section of declining frequency over a first period of time and a section of increasing frequency over a second period of time. This information indicates either fracture growth (declining ridge) or fracture growth stoppage such as, for example, closure or screenout (increasing ridge).
[0074] Thus, the present invention is well adapted to carry out the objects and attain the ends and advantages mentioned above as well as those inherent therein. While preferred embodiments of the invention have been described for the purpose of this disclosure, changes in the construction and arrangement of parts and the performance of steps can be made by those skilled in the art, which changes are encompassed within the spirit of this invention as defined by the appended claims. | Changes occurring downhole during a fracturing process can create or reflect pressure signals. Capturing and evaluating such pressure waves during fracturing enables personnel to monitor, in real time or later, what happens downhole. When a fracture extends, a burst of acoustic noise is embodied in a pressure wave or signal, as is noise coming from other sources. By transforming time-based pressure signals to a frequency base, one can monitor this acoustic noise. In a particular implementation, a waterfall plot of frequency spectra at successive time slices of the original signal is used to determine frequency ridges, such as a ridge of decreasing frequencies indicates fracture extension and a ridge of increasing frequencies indicates either closure or proppant backing up in the fracture. Filtering, such as wavelet filtering, can be used. A fracturing process can be controlled in response to determining whether the fracture is extending. | 4 |
BACKGROUND OF THE INVENTION
I. Field of the Invention
The present invention relates generally to a chlorination and dechlorination method for the treatment of wastewater or other fluid, or to a chlorination method for the treatment of potable water, and also to an apparatus used in carrying out this method. In particular, the apparatus of the present invention comprises a chlorination unit, a contact tank, and a dechlorination unit for the treatment of wastewater. For potable water treatment, the apparatus comprises a chlorination unit and a contact tank.
II. Background and Description of the Related Art
For years, chlorine has been used extensively as a disinfectant in water and wastewater treatment processes. In fact, chlorine is perhaps the most common water and wastewater disinfectant in use throughout the world today. In large potable water treatment plants or wastewater treatment plants, chlorine gas or liquid is commonly used as a disinfectant. In small plants such as home wastewater treatment plants and in some commercial wastewater treatment plants, chlorine tablets, which are mainly composed of calcium hypochlorite, are used as a disinfectant.
For example, U.S. Pat. No. 5,133,381 to Wood et al. discloses a chemical dispenser for swimming pools which utilizes calcium hypochlorite tablets arranged loosely in a chemical chamber for sanitizing water supplied to a swimming pool. U.S. Pat. Nos. 3,899,425 to Lewis, 4,210,624 to Price, and 5,089,127 to Junker et al. all disclose the use of chlorine tablets for the disinfection of swimming pool water. In these references, however, the tablets are stacked in feeder tubes. Water washes over tablets in the tube, releasing chlorine into the water. U.S. Pat. Nos. 4,584,106 to Held and 3,579,440 to Bradley, Jr. disclose the use of chlorine tablets in conjunction with similar feeder devices for the treatment of hot tub water and sewage water, respectively.
There are four parameters which must be controlled when using tablets in chlorination and dechlorination processes, i.e., (1) chlorine tablet dissolve rate, (2) contact time, (3) flow pattern and (4) dechlorination tablet dissolve rate. Controlling these parameters will result in consistent chlorine residual.
The dissolve rate of chlorine tablets is determined in part by tablet quality and also by the design of the tablet feeder and weir.
Contact time is set as required by the Environmental Protection Agency ("E.P.A.") and local health departments. Because of the importance of contact time, careful attention must be given to the design of the contact chamber so that at least 80 to 90 percent of the wastewater or potable water is retained in this chamber for the specified contact time. The best way to achieve this contact time is by using a plug-flow, otherwise known as laminar flow, type of contact chamber which can be realized by using a series of interconnected basins or compartments.
Thus, the third parameter, flow pattern, can help control contact time. In a plug-flow contact chamber, all fluid within a fluid flow cross section of the flow path is moving at substantially the same flow rate, minimizing short circuiting. Short circuiting occurs when some of the fluid in the flow path moves at a different rate than fluid flowing beside it. Short circuiting results in nonuniform detention times for fluid in the chamber and can be minimized by utilizing a plug-flow design. Such a contact chamber design is disclosed in U.S. Pat. No. 2,955,923 to Atkinson. The Atkinson contact chamber is filled with loose treatment material which dissolves into the water as it passes through the chamber. As previously stated, these types of designs inhibit the development of dead zones with respect to flow that would otherwise reduce the hydraulic detention times. Length-to-width ("L/W") ratios for the contact chamber flow path of at least about 10 to 1 and preferably 40 to 1 will further minimize short circuiting. Short circuiting may also be minimized by reducing the velocity of the wastewater entering the contact tanks.
As with the chlorination tablet dissolve rate, the dissolve rate of the dechlorination tablets is determined in part by tablet quality and also by the design of the tablet feeder and weir.
Based upon the above factors, the L/W ratio and contact detention time are the two most important parameters for a contact tank design. Contact tanks currently on the market for home wastewater treatment plants are deficient in these two areas. The volume of some contact tanks is too small and the detention time is too short. Some of them have L/W ratios that are less than 10 to 1 because they do not utilize plug-flow designs.
Control of the tablet dissolve rate is an important factor in effective wastewater treatment design. Weirs are typically used to control the water line in tablet feeders and supporters, which in turn helps control the tablet dissolve rate. The principle behind weir design is that the flow rate of fluid entering a tablet feeder supporter is proportional to the water depth in the feeder supporter. The contact surface area of the tablets is likewise proportional to the water depth in the feeder supporter. Thus, more calcium hypochlorite is dissolved during high flow rate periods and less calcium hypochlorite is dissolved during low flow rate periods. The feeder supporter weir, which controls the water line and therefore the flow rate, can be designed such that the chlorine residual can be maintained at a consistent level.
The weirs used in some chlorinator products are too wide to obtain the required chlorine residual. These weirs are only suitable for commercial plants, not for home plants. U.S. Pat. No. 4,759,907 to Kawolics et al. discloses a dissolution chamber having chemical tablet feeder devices and adjustable weirs for controlling the flow rate. However, the dimensions of the example chamber disclosed in the reference are such that the L/W ratio is only slightly greater than 2, and the design of the chamber does not allow any flexibility to increase this ratio.
The chlorinator and dechlorinator are separated from the contact tank in most plant designs, which results in more expense when installing a chlorination and dechlorination system, and makes maintenance of the plant difficult. This cost can be greatly reduced and maintenance simplified if the chlorinator, contact tank and dechlorinator are built in one unit, in contrast to the inefficient designs that are prevalent today.
Faced with the foregoing difficulties in the application of a chlorination and dechlorination process, a new chlorination and dechlorination apparatus has been developed to provide an optimum treatment unit which possesses the advantages of a plug-flow pattern, consistent chlorine residual, high efficiency, and easy maintenance.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a chlorination and dechlorination unit which comprises an integral chlorinator, contact tank and dechlorinator.
It is a further object of the present invention to provide two optimumly designed feeder supporters.
It is another object of the present invention to provide two water line control weirs which are located in the chlorinator supporter and dechlorination supporter.
It is a further object of the present invention to provide a plug-flow contact tank in which the L/W ratio is greater than about 10 to 1.
It is an additional object of the present invention to provide a contact tank design which optimizes contact detention time.
It is also an object of the present invention to provide a contact tank design in which the chlorinator and the dechlorinator are located proximate to each other, simplifying maintenance of the system.
These and other objects and advantages of the present invention will be apparent to those skilled in the art upon examining the detailed description, drawings, and appended claims.
The present invention comprises a chlorinator, a contact tank and a dechlorinator. The contact tank is a closed hollow vessel having an inlet opening on one side near the top and an outlet opening approximately opposite the inlet opening. The contact tank is closed on top by a contact tank cover, which seals the contact tank except for a chlorinator opening and a dechlorinator opening to accommodate the chlorinator and dechlorinator, respectively.
The chlorinator comprises a chlorine tablet feeder, a chlorine tablet feeder supporter, and a feeder housing. The chlorine tablet feeder supporter is located within the contact tank and is attached to the inlet opening so as to provide an influent path from the influent opening to the lower end of the chlorine tablet feeder, which rests on the base of the chlorine tablet feeder supporter. The upper end of the chlorine tablet feeder protrudes from the chlorinator opening and is enclosed by a covered feeder housing. An influent line may be connected to the inlet opening from outside the contact tank.
The dechlorinator comprises a dechlorination tablet feeder, a dechlorination tablet feeder supporter, and a feeder housing. The dechlorination tablet feeder supporter is located within the contact tank and is attached to the outlet opening so as to provide an effluent path from the lower end of the dechlorination tablet feeder to the effluent opening, the dechlorination tablet feeder resting on the base of the dechlorination tablet feeder supporter. The upper end of the dechlorination tablet feeder protrudes from the dechlorinator opening and is enclosed by a covered feeder housing. An effluent line may be connected to the outlet opening from outside the contact tank.
The contact tank is divided into two contact chambers by a divider means or baffle which runs vertically the entire length of the contact tank. A baffle opening is provided at the lower end of the baffle to allow passage of fluid from the first contact chamber to the second contact chamber, fluid passage between the chambers being otherwise completely prevented by the baffle.
The influent containing microorganisms is flowed through the influent line and inlet opening, the chlorine tablet feeder supporter and the chlorine tablet feeder which contains stacked chlorine tablets. The influent washes the chlorine tablets and dissolves the calcium hypochlorite composing the tablets, releasing chlorine into the influent. The chlorine containing influent then flows through a U-notch weir and down into the contact tank. The chlorine containing influent flows to the bottom of the first chamber in the plug-flow pattern and passes through the baffle opening at the bottom of the baffle to the second chamber. The chlorine containing influent then flows up to the dechlorinator. The chlorine containing influent then flows through a dechlorination opening and washes dechlorination tablets which are stacked in the dechlorination tablet feeder. The treated effluent, which is the dechlorinated chlorine containing influent, then flows out through a U-notch weir to the effluent line.
The chlorine tablet feeder supporter and the dechlorination tablet feeder supporter are glued or otherwise attached to the inlet opening and the outlet opening, respectively from within the contact tank. The feeder housings are glued or otherwise attached to the chlorinator opening and the dechlorinator opening. The chlorine tablet feeder and dechlorination tablet feeder rest on the respective tablet feeder supporters. The two housings are covered to prevent chlorine gas leaks.
The design of the contact tank provides a L/W ratio of at least about 10 to 1, yet the tank is compact in design. The chlorinator and dechlorinator are proximate to each other, simplifying maintenance of the system. The design of the present invention is therefore more efficient than other designs currently in use.
When the chlorine tablets or dechlorination tablets are used up, the operator or plant owner can open the feeder cover and lift the feeder for tablet replacement.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of an assembled chlorination and dechlorination apparatus.
FIG. 2 is a schematic diagram of two connected contact tanks.
FIG. 3a is a plan view of a contact tank cover.
FIG. 3b is a side view of a contact tank cover.
FIG. 3c is an end view of a contact tank cover.
FIG. 4a is a top view of a chlorine tablet feeder supporter.
FIG. 4b is a side view of a chlorine tablet feeder supporter.
FIG. 4c is an end view of a chlorine tablet feeder supporter.
FIG. 5a is a top view of a dechlorination tablet feeder supporter.
FIG. 5b is a side view of a dechlorination tablet feeder supporter.
FIG. 5c is an end view of a dechlorination tablet feeder supporter.
FIG. 6 is a schematic diagram of a tablet feeder.
FIG. 7 is a schematic diagram of the apparatus and a treatment plant, such as might suitably be used in the practice of the present invention.
FIG. 8a is a side view of a contact chamber outlet weir.
FIG. 8b is an end view of a contact chamber outlet weir.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, the chlorination and dechlorination apparatus is described. Influent to be treated enters the apparatus via influent line 1. This influent may be derived from a variety of sources and may be, for example, wastewater treatment plant effluent or filter effluent. From influent line 1, the influent enters contact tank 2 through inlet opening 3. The contact tank 2 is divided into a first contact chamber 22 and a second contact chamber 23 by a baffle 5 or other divider means, and includes a contact tank cover 29. A chlorine tablet feeder 11 which holds stacked chlorine tablets 12 is located within a feeder housing 14a which is glued or otherwise attached within a chlorinator opening 4 in the contact tank cover 29. The chlorine tablet feeder 11 rests on the base of a chlorine tablet feeder supporter 10. The influent enters the chlorine tablet feeder supporter 10 and passes through the bottom portion of the chlorine tablet feeder 11 through openings in the bottom portion of the chlorine tablet feeder 11. When the influent washes the surface of the chlorine tablets 12, the calcium hypochlorite which is the main component of the tablets is dissolved into the influent. The chlorine-containing influent then passes through a chlorinator U-notch weir 13 which is an outlet of the chlorine tablet feeder supporter 10 and flows downward in the first contact chamber 22 until it reaches the bottom of the first contact chamber 22 in the plug-flow pattern. The first contact chamber 22 and the second contact chamber 23 are separated by a baffle 5. A baffle opening 6 is located at the bottom of the baffle 5 which allows the chlorine containing influent to enter the second contact chamber 23. The baffle opening 6 is the sole fluid passage between the first contact chamber 22 and the second contact chamber 23. The baffle opening 6 may be a single opening or it may be, for example, a plurality of openings in the baffle 5, all of which are located at the bottom-most portion of the baffle 5.
The chlorine containing influent flows upward into the second contact chamber 23 in the plug-flow pattern until it arrives at the dechlorination opening 16 on the dechlorination tablet feeder supporter 18 which is glued or otherwise attached to the inside of the outlet opening 8. A dechlorination tablet feeder 20, which holds stacked dechlorination tablets 17, is located within a feeder housing 14b which is glued onto a dechlorinator opening 7 in the contact tank cover 29. The dechlorination tablet feeder 20 rests on the base of a dechlorination tablet feeder supporter 18. Feeder housing 14b is identical to feeder housing 14a. The chlorine containing influent enters the dechlorination tablet feeder supporter 18 through dechlorination opening 16, washes the dechlorination tablets 17, and flows out through a dechlorinator U-notch weir 19 in an effluent weir plate 24 located in the dechlorination tablet feeder supporter 18 and then through an effluent line 21. The dechlorination agent composing the dechlorination tablets 17, sodium sulfite for example, is dissolved into the chlorine-containing influent. By this chemical action, chlorine is removed at a rate calculated to maintain a certain concentration of chlorine residual which must meet the E.P.A. or local requirements.
The feeder housings 14a and 14b are covered by a cover means to prevent chlorine gas leakage. In the preferred embodiment, the feeder housings 14a and 14b are connected by a feeder cover support 25 which is glued or otherwise attached to the feeder housings 14a and 14b and has an opening for lock bar 35. The feeder housings 14a and 14b are covered by a feeder cover 15, which rests on the feeder cover support 25 and can be locked to it by lock bar 35 to secure the feeder cover 15 in place.
The contact tank 2 is therefore made of four pieces, i.e., two contact chambers 22 and 23, a contact tank cover 29, and one baffle 5 with baffle opening 6. These four pieces are glued or molded together to make the contact tank 2. Alternatively, the two contact chambers 22 and 23 may be constructed with integral covers, so that the contact tank cover 29 is not necessary. The effective ratio of the length to the width of each contact chamber is at least 5 to 1, so that the L/W ratio of the fluid path within the contact tank 2 is no less than about 10 to 1.
If one tank is used, the dimensions of the contact tank 2 meet the L/W ratio requirement of 10 to 1. The plug-flow pattern is formed by the two narrow chambers 22 and 23. Two openings, 4 and 7, located at the top of the contact tank 2 are used to locate feeder housings 14a and 14b, respectively, which are used to enclose the chlorine tablet feeder 11 and the dechlorination tablet feeder 20, respectively. In order to save on manufacturing costs, the first contact chamber 22 and the second contact chamber 23 can be made to the same dimensions. Inlet opening 3 and outlet opening 8 can be located at the same level.
Referring to FIG. 2, a diagram of two connected contact tanks is shown. For some applications, an L/W ratio of 20 to 1 is required. In such a situation, two contact tanks can be serially joined by connecting the outlet opening 8 of a first contact tank 2 with the inlet opening 48 of a second contact tank 40 with a pipe (which can be the effluent line 21 of the first contact tank 2). The first contact tank 2 is also connected to the second contact tank 40 by alignment means. These alignment means provide an extra connection point between the first contact tank 2 and the second contact tank 40. The alignment means can take the form of, for example, alignment buttons 9. These alignment buttons 9 protrude from raised portions on the sides of the contact tanks 2 and 40, and engage with corresponding recesses located next to the alignment buttons of the other contact tank. The alignment buttons and recesses are the means for aligning the contact tanks 2 and 40 so that they can be attached together by, for example, gluing. The alignment buttons 9 are only one form of alignment means contemplated for use with the present invention. Other possible alignment means include connection pipes, braces, and other equivalent means for connecting a first contact tank to a next contact tank.
When connected in this manner, only one chlorinator and one dechlorinator are used. A chlorinator is attached at the chlorinator opening 4 of the first contact tank 2 and a dechlorinator is attached at the dechlorinator opening 46 of the second contact tank 40. The dechlorinator opening 7 of the first contact tank 2 and the chlorinator opening 44 of the second contact tank 40 are unused and may be closed off.
In such a configuration, influent enters the influent opening 3 of the first contact tank 2 and is treated at a chlorinator located on the inside of the influent opening as previously described and shown in FIG. 1. The chlorine containing influent then flows through the first contact chamber 22 and the second contact chamber 23. After flowing through the outlet opening 8 of the first contact tank 2 and into the inlet opening 48 of the second contact tank 40 through a pipe (or effluent line 21), the chlorine containing influent flows through a third contact chamber 52 and a fourth contact chamber 54 before being treated at a dechlorinator as previously described and shown in FIG. 1. Thus, a cumulative L/W ratio of 20 to 1 is provided by using individual contact tanks, each having a L/W ratio of about 10 to 1. Any number of contact tanks may be serially linked in this manner in order to achieve a desired L/W ratio. The actual L/W ratio achieved will be variable, depending on the number of contact tanks connected. If desired, a number of contact tanks may be connected in parallel from the first contact tank. That is, the outlet opening of the first contact tank may be connected to an effluent line that splits into two or more paths, each connected to the inlet opening of another contact tank. Serial connection from a first contact tank to a next contact tank is preferred, however.
In the preferred embodiment, the inside diameters of inlet opening 3 and outlet opening 8 are designed to fit PVC pipe and feeder supports 10 and 18 and PVC pipe as influent and effluent lines. This pipe can be used to connect the outlet and inlet openings of first and second contact tanks to be used as a two tank unit in order to meet stricter requirements of chlorine detention time and L/W ratio. The alignment buttons 9 can be connected, supplying an additional two connection points between the contact tanks, preventing twisting between the tanks.
Referring to FIG. 3a, the top plan view of the contact tank cover 29 is shown. This view shows the chlorinator opening 4 and the dechlorinator opening 7. As shown in FIG. 3a, FIG. 3b, the side view of the contact tank cover, and FIG. 3c, an end view of the contact tank cover, the openings 4 and 7 are specially designed to include an annular ledge or step 31. The feeder housings 14a and 14b rest on the step 31 and are attached to the contact tank cover 29.
Referring to FIG. 4a, a top view of a chlorine tablet feeder supporter 10 is shown. The chlorine feeder supporter 10 comprises a chlorine feeder base 28, an inlet connector 30, and a chlorinator U-notch weir 13. The inlet connector 30 is a cylindrical projection from the base 28. The base 28 has a flat bottom portion surrounded by a wall portion with an open top, as shown in FIG. 4b, a side view of the chlorine tablet feeder supporter. The wall portion is continuous except for the interface with the inlet connector 30 and the U-notch weir 13. The U-notch weir 13 is shown more clearly in FIG. 4c, an end view of the chlorine tablet feeder supporter.
The base 28 provides support for the chlorine tablet feeder 11, while the inlet connector 30 fits inside and is attached to the inlet opening 3, providing a fluid passage from the inlet opening 3 to the lower end of the chlorine tablet feeder 11, which rests on the base 28. The U-notch weir 13, located on the wall portion of the base 28, provides a fluid passage from the lower end of the chlorine tablet feeder 11 to the first contact chamber 22.
Referring to FIG. 5a, a top view of a dechlorination tablet feeder supporter 18 is shown. Likewise, the dechlorinator feeder supporter 18 comprises a dechlorination feeder base 32, an outlet connector 34, and a dechlorination opening 16, the outlet connector 34 being a cylindrical projection from the base 32. The base 32 has a flat bottom portion surrounded by a wall portion with an open top, as shown in FIG. 5b, a side view of the dechlorination tablet feeder supporter. The wall portion is continuous except for the interface with the outlet connector 34 and the dechlorination opening 16. The dechlorination opening 16 is shown more clearly in FIG. 5c, an end view of the dechlorination tablet feeder supporter.
The base 32 provides support for the dechlorination tablet feeder 20, while the outlet connector 34 fits inside and is attached to the outlet opening 8, providing a fluid passage from the lower end of the dechlorination tablet feeder 20, which rests on the base 32, to the outlet opening 8. An effluent weir plate 24 is glued or otherwise attached inside the outlet connector 34, as shown in FIG. 5b. A U-notch weir 19 in the effluent weir plate 24 provides a fluid passage from the lower end of the dechlorination tablet feeder 20 to the outlet opening 8.
The U-notch weirs 13 and 19 are used to control the fluid levels in the tablet feeders 11 and 20. The fluid levels in the tablet feeders refers to the depth the fluid will reach in the chlorinator and dechlorinator. The tablet feeders sit within the base sections of the tablet feeder supporters. Because the tablet feeder supporter bases are enclosed by wall portions, the fluid in the tablet feeder supporters can rise to a certain level. The U-notch weirs 13 and 19 are used to control this level. Because the fluid within the tablet feeder supporters is the fluid in contact with the treatment tablets, the fluid level in the tablet feeder supporters is proportional to the tablet/fluid contact area, and therefore to the tablet dissolve rate. The U-notch weirs 13 and 19 may be other shapes as well. V-notch weirs or square notch weirs will also work, for example. U-notch weirs are preferred due to manufacturing considerations.
After the two tablet feeder supporters are assembled in the contact tank 2, the fluid level at the U-notch weir of the chlorine tablet feeder supporter 10 is higher than the fluid level at the U-notch weir of the dechlorination tablet feeder supporter 18 to facilitate fluid flow through the plug-flow pattern.
The tablet feeder supporters 10 and 18 are designed such that they have a special shape which offers limited distance between the outside walls of the tablet feeders and the inside walls of the bases 28 and 32 on the supporters 10 and 18, maximizing fluid contact with tablets 12 and 17. The U-notch weirs 13 and 19 in the present invention are designed to control the low flow rate fluid line in the feeders 11 and 20. The fluid line is the key point for dissolve rate control. Dechlorination opening 16 is used as an opening for chlorine-containing influent and is also designed to maintain the strength of supporter 18.
Referring to FIG. 6, a chlorine tablet feeder 11 used with the present invention is described. In the preferred embodiment, the outside diameter of the chlorine tablet feeder 11 is greater than 3.2 inches. There are preferably six slots 26 on the feeder although any number of slots or other type of opening is contemplated. The slots are the openings which allow liquid to flow in and out of the feeder to contact the chlorine tablets 12 in feeder 11. Dechlorination tablet feeder 20 includes similar features and can be constructed to be identical to chlorination tablet feeder 11.
The chlorination and dechlorination apparatus can be connected to a settling tank, or a filter, or another treatment unit with a 4-inch or appropriately sized pipe. The connector pipe may be connected as an influent line 1 between the output of the treatment unit and the inlet opening 3. Also, as shown in FIG. 7, the apparatus can be connected directly to the effluent pipe of a treatment plant 27.
Referring to FIGS. 8a and 8b, an effluent weir plate 24 with a U-notch weir 19 is shown. The effluent weir plate 24 is glued, welded, or otherwise attached inside the dechlorination tablet feeder supporter 18 to control the water line in the dechlorinator feeder. The effluent weir plate 24 may also be constructed integrally with the dechlorination tablet feeder supporter 18.
The apparatus of the present invention is very flexible as to possible L/W ratios. As described previously, L/W ratios of at least 10 to 1 and preferably 40 to 1 will minimize short circuiting. Any L/W ratio requirement can be met by the present invention. The L/W ratio of each individual unit is preferably at least about 10 to 1 and units may be combined to achieve greater L/W ratios. For example, if a 30 to 1 ratio is required, three units can be connected in series.
For potable water treatment, or in applications in which only chlorination is necessary, the dechlorinator may be left out or removed, or may be left in place without dechlorination tablets to utilize the U-notch weir 19 for water level control. If the dechlorinator is left out, the dechlorinator opening 7 may be closed off. Likewise, if a number of contact tanks are connected in series for chlorination purposes only, only the first chlorinator will be used. All other chlorinator openings and dechlorinator openings may be closed off.
The apparatus of the present invention is preferably made of a plastic material, such as PVC, ABS or polyethylene. Alternatively, however, it can also be made of concrete or other material. The connection of the pipes of the apparatus can be by either a gluing method or any other fixing method.
Preferred and alternate embodiments of the present invention have now been described in detail. It is to be noted, however, that this description is merely illustrative of the principles underlying the inventive concept. It is, therefore, contemplated that various modifications of the disclosed embodiments will, without departing from the spirit and scope of the present invention, be apparent to persons skilled in the art. | A chlorination and dechlorination apparatus and method for the treatment of wastewater or other fluid including a chlorinator, a contact tank, and a dechlorinator. The contact tank is a vessel having an inlet opening and an outlet opening and is divided into two contact chambers by a baffle which runs vertically the entire length of the contact tank. A baffle opening is provided at the lower end of the baffle to allow passage of fluid from the first contact chamber to the second contact chamber. The chlorinator includes a chlorine tablet feeder and the dechlorinator includes a dechlorination tablet feeder. The fluid under treatment flows from the inlet opening to the outlet opening in a plug-flow pattern. Previous to entering the contact chambers, the fluid washes over and dissolves chlorine tablets stacked in the chlorine tablet feeder. After flowing through the contact chambers, the fluid washes over and dissolves dechlorination tablets stacked in the dechlorination tablet feeder. U-notch weirs control the fluid levels in the chlorinator and dechlorinator, regulating the tablet dissolve rate. The length to width ratio of the fluid path in the contact tank is at least about 10 to 1, permitting a satisfactory contact time for the chlorinated water. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an outboard motor electronic part unit.
[0003] 2. Description of Related Art
[0004] A conventional outboard motor is sometimes provided with a V-type engine. An embodiment is explained with reference to FIGS. 6 and 7. As shown in FIG. 6, outboard motor 1 is detachably mounted on a board (not shown) via attaching bracket 2 . As shown in FIG. 7, engine 3 is covered with cover 4 which is formed in a cross-sectional tapered shape tapering to the rear side from the front side along the shape of engine 3 .
[0005] A side surface of engine 3 has attached thereto electronic part unit 5 which is formed by arranging electronic control parts of engine 3 into a unit and has a rectangular parallelepiped shape.
[0006] However, in the above conventional art, in order to prevent interference with the inner surface of the rear part of cover 4 with a square part of the rear part of electronic part unit 5 , electronic part unit 5 is required has its attachment position adjusted or cover 4 is required to be molded a slightly larger. Therefore, there have been problems in that the attachment position of electronic part unit 5 is considerably limited and cover 4 is enlarged.
[0007] For example, if electronic part unit 5 is not attached, it is sufficient to form cover 4 which has a size shown by a dash-dot-dot line in FIG. 7. If electronic part unit 5 is attached, since cover 4 has a cross-sectional tapered shape, cover 4 is required to be enlarged to the size shown by a continuous line in FIG. 7 in order to avoid cover 4 interfering with the square part of the rear part of electronic part unit 5 .
[0008] On the other hand, if the height of electronic part unit 5 can be reduced, in other words, if the length of the part protruding from engine 3 can be shortened, cover 4 is not required to be enlarged. However, since discrete parts which require a certain height are used on the circuit board in electronic part unit 5 , the height of electronic part unit 5 cannot simply be reduced.
[0009] Furthermore, the above electronic part unit 5 is filled with resin for waterproofing; however, the weight of the resin causes an increase in the weight of the outboard motor, and this is a problem.
BRIEF SUMMARY OF THE INVENTION
[0010] To solve the above problems, an object of the present invention is to provide an outboard motor electronic part unit which is able to be attached to a desired place of the side surface of engine, and is reduce in size and is lighter.
[0011] A first aspect of the present invention is to provide an outboard motor electronic part unit provided between an engine for a boat and a cover covering the engine, comprising a case which is attached to the engine or the cover and is provided along a space formed between the engine and the cover; and a circuit board equipped with a connector which is housed and fixed in the case, wherein an inclined surface in which a height thereof is great at the connector and low at a distal portion far from the connector, is provided in the case.
[0012] For example, the engine may be referred to as engine 3 , the cover may be referred to as cover 6 , the outboard motor electronic part unit may be referred to as outboard motor electronic part unit 8 , the space may be referred to as space 7 , the case may be referred to as case 9 , the connector may be referred to as connector 10 , 11 , or 12 , the circuit board may be referred to as circuit board 13 , and the inclined surface may be referred to as inclined surface 93 a , which are described in embodiments which are explained below.
[0013] According to the above structure, since the case has a small height by providing the inclined surface, the space occupied by the case can be small. Furthermore, the case can be provided in the space formed between the engine and the cover without interfering with the cover. Therefore, the limitation of the mounting position of the case to the engine is decreased and the outboard motor electronic part unit is smaller and lighter.
[0014] Furthermore, in the outboard motor electronic part unit, the circuit board may be mounted with parts having a large height among circuit parts near the connector and with parts having a lesser height among circuit parts in the distal direction from the connector so as to be housed in the case having the inclined surface.
[0015] For example, the parts having a great height are referred to as discrete parts 15 and 16 which are described in the embodiments which are explained below.
[0016] According to the above structure, since the case has a reduced height by providing the inclined surface, the space occupied by the case can be small. Circuit parts can be mounted along the inclined surface in the case, in which parts having a large height among circuit parts are mounted near the connector and with parts having lesser heights among circuit parts in the distal direction from the connector.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] [0017]FIG. 1 is a cross-sectional view taken on line A-A in FIG. 6 of an embodiment of the present invention.
[0018] [0018]FIG. 2 is a perspective view of an embodiment of the present invention.
[0019] [0019]FIG. 3 is a cross-sectional view taken on line B-B in FIG. 2 of an embodiment of the present invention.
[0020] [0020]FIG. 4 is a cross-sectional view showing an embodiment of the present invention.
[0021] [0021]FIG. 5 is a cross-sectional view showing an embodiment of the present invention.
[0022] [0022]FIG. 6 is a perspective view of an embodiment of the present invention or of a conventional example.
[0023] [0023]FIG. 7 is a cross-sectional view taken on line A-A in FIG. 6 of a conventional example.
DETAILED DESCRIPTION OF THE INVENTION
[0024] An embodiment of the present invention will be explained with reference to FIGS. 1 to 5 with reference to FIG. 6.
[0025] As shown in FIG. 1, V-type engine 3 for an outboard motor is equipped with cover 6 via a bracket (not shown) so as to cover engine 3 with cover 6 .
[0026] In order to cover engine 3 , cover 6 is formed into a tapered shape having a planar cross section so as to be wide at a cylinder portion placed at the front side and narrow at the rear side. Therefore, space 7 is formed between engine 3 and cover 6 , that is, is formed at both sides of the rear portion, wherein space 7 is formed into a tapered shape having planar cross section.
[0027] Outboard motor electronic part unit 8 to be mounted on engine 3 is provided in space 7 .
[0028] As shown in FIGS. 2 and 3, outboard motor electronic part unit 8 is equipped with case 9 and circuit board 13 .
[0029] Case 9 is mounted on engine 3 and is formed into a tapered shape having a planar cross section so as to be provided in space 7 formed between engine 3 and cover 6 .
[0030] One side of case 9 , which is corresponding to connectors 10 , 11 , and 12 to be explained below, is formed as opening 90 , and the other side is closed. That is, opening 90 is formed by planar bottom surface 92 , upper surface 93 , and two side surfaces 94 so as to be open. Upper surface 93 is formed of inclined surface 93 a which is high at opening 90 and low at bottom surface 92 , and planar surface 93 b which is formed continuously in parallel to bottom surface 92 . Case 9 is formed into a tapered shape when shown from a side surface side. Furthermore, as shown in FIG. 2, brackets 95 to be mounted on engine 3 are equipped on each side surface 94 and the other side surface 95 of case 9 .
[0031] The height h between the upper surface of planar surface 93 b of upper surface 93 and the lower surface of bottom surface 92 is less than the interval d at the portion corresponding to the above cover 6 and engine 3 .
[0032] Circuit board 13 is set by inserting it into engaging portion 14 which is provided inside the other side 91 in case 9 . Circuit board 13 is equipped with connectors 10 , 11 , and 12 , and adjacently discrete parts 15 and 16 having a relatively large height, such as a power transistor, power zener diode, condenser, and the like, so as to be high at a front portion and low at a rear portion.
[0033] Moreover, in the state of setting circuit board 13 into case 9 , opening 90 opens upward as shown in FIG. 4, and resin 17 for waterproofing is filled in case 9 as shown by hatching in FIG. 5, and as a result, outboard motor electronic part unit 8 is produced.
[0034] According to the above embodiment, outboard motor electronic part unit 8 is formed into a tapered shape having a planar cross section. Furthermore, since outboard motor electronic part unit 8 is provided in space 7 having a tapered shape having a planar cross section formed between engine 3 and case 9 , and is fixed to engine 3 by each bracket 95 , interference between cover 6 for covering engine 3 and case 9 of outboard motor electronic part unit 8 , in particular, interference at a rear portion side is prevented. Therefore, outboard motor electronic part unit 8 can be mounted at any desired place without limitation.
[0035] Among parts mounted on circuit board 13 of outboard motor electronic part unit 8 , connectors 10 , 11 , and 12 , and discrete parts 15 and 16 having a relatively large height are provided on circuit board 13 so as to correspond to the opening 90 side of case 9 which is corresponding to the large cross-sectional area portion of space 7 , and other parts having a relatively small height are provided on circuit board 13 so as to correspond to the small cross-sectional area portion of space 7 . Conventionally, case 9 is formed into a rectangular parallelepiped; however, in the present invention, case 9 is molded into a tapered shape which favors being provided in space 7 , so that outboard motor electronic part unit 8 can be small and lightened. Therefore, cover 6 can be small and outboard motor 1 can also be small.
[0036] Furthermore, since outboard motor electronic part unit 8 is formed into a tapered shape, in comparison with unit 8 formed into a rectangular parallelepiped, volume of case 9 decreases and then a required amount of resin to be filled decreases. As a result, manufacturing cost decreases, weight of parts decreases, and also fuel consumption is improved.
[0037] Moreover, since a cross-sectional area of case 9 increases toward opening 90 , when case 9 is filled with resin 17 , as filling is nearly completed, the liquid surface rise rate of resin 17 decreases. Therefore, resin 17 can be filled to a predetermined position of the lower portion of opening 90 without loss.
[0038] If case 9 is a rectangular parallelepiped and has a uniform cross-sectional area conventionally, in comparison with the above-described, since resin 17 to be filled has a large liquid surface rise rate, and it is difficult to stop filling resin 17 just under opening 90 . Therefore, resin 17 must be filled into case 9 up to overflow.
[0039] On the other hand, in this embodiment of the present invention, since the liquid surface rise rate of resin 17 filled during the completion is low, it is easy to time the stopping of the filling of the resin 17 . Therefore, supplying resin 17 can be stopped before resin 17 overflows. As a result, excess overflowing resin 17 is not required. Since the volume of case 9 decreases, the amount of resin to be used can be remarkably decreased.
[0040] Additionally, the present invention is not limited to the above-described embodiment, and for example, any discrete parts can be used as long as the discrete parts have a relatively large height other than power transistor, the power zener diode, or condenser.
[0041] Furthermore, in this embodiment, the upper surface 93 of case 9 is composed of inclined surface 93 a and planar surface 93 b ; however, the upper surface may be composed of only inclined surface 93 a without planar surface 93 b.
[0042] Optionally, outboard motor electronic part unit 8 may be equipped on cover 6 . | An outboard motor electronic part unit provided between an engine for a boat and a cover covering the engine, comprises a case which is attached to the engine or the cover and is provided along a space formed between the engine and the cover; and a circuit board equipped with a connector which is housed and fixed in the case, wherein an inclined surface in which a height thereof is large near the connector and small near a distal portion far from the connector, is provided in the case. | 5 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application Ser. No. 62/125,404 filed on Jan. 20, 2015 which is incorporated by reference herein in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to the field of systems used to sense and report the impact of a bullet or other projectile upon a distant target especially when such impact is too small to be detected either visually or by sound.
BACKGROUND OF THE INVENTION
[0003] A BB gun, pellet gun, air soft rifle, rifle, crossbow, bow and arrow or other device for shooting projectiles is often used for target practice. When the projectile hits a metal target there is only a modest ping sound from a BB or 22, or no detectible sound from a pellet rifle such as is used in competition. Air soft guns are replica guns which use non-lethal ammunition such as plastic pellets, paper balls, and eraser chunks.
[0004] During target practice, it is desirable that a target is not consumed or ruined by a few hits. Otherwise the target must be renewed frequently. Paper bull's eye type targets are well known but are useable for only a few hits and must be scored from a vantage point nearer than the shooting position. This fact renders paper targets as undesirable. Metal targets such as shown in FIG. 3 are available in various sizes. Some are designed to flip up out of the way when hit but then must be lowered back to the shooting position. Some are provided with a top target which, when hit, resets the rest of the targets. Still, such metal targets don't give the desirable audible report.
[0005] Paint ball competition, a game wherein shooters use guns which shoot small plastic paint balls filled with paint, at one another, has become very popular. The balls rupture when they impact the target, and thus, the target is marked visibly by the paint as a hit. Sometimes, competition is done in dark areas. This can make a hit harder to see. Because competitors wear protective equipment, it is often not obvious who was hit or if anyone was hit.
DESCRIPTION OF THE RELATED ART
[0006] U.S. Pat. No. 5,095,433 by Botarelli et al for TARGET REPORTING SYSTEM which issued on Mar. 10, 1992 teaches a target with a plurality of sensors connected to a controller which transmits a message to a receiver with a loudspeaker to inform the shooter approximately where his hit occurred.
[0007] U.S. Pat. No. 7,891,231 by Song for APPARATUS FOR MONITORING AND REGISTERING THE LOCATION AND INTENSITY OF IMPACTS IN SPORTS which issued on Feb. 22, 2011 teaches a garment such a vest with pads spaced out over the vest, each pad containing an impact sensor. The sensors wirelessly transmit impact data to a receiver for registering and display of the data. The impacts result from opponents landing blows during boxing, martial arts, fencing and the like.
[0008] U.S. Pat. No. 8,356,818 by Mraz for DURABLE TARGET APPARATUS AND METHOD OF ON-TARGET VISUAL DISPLAY which issued on Jan. 22, 2013 teaches a durable target with pie shaped areas individually monitored by separate impact sensors connected to a controller. The impact sensor information is relayed to the shooter, telling him or her in which pie shaped area the hit occurred.
SUMMARY OF THE INVENTION
[0009] In accordance with the present invention, comprises or consists of a combination of software and hardware executed on a mobile device (smart phone, tablet, watch, etc.) that can monitor available inputs during firearm target shooting such as a system for large and small caliber rifles, pistols, revolvers, bb/pellet guns, airsoft guns, slingshots, etc. The system detects hits on the targets, records all relevant hit data, indicates the hits to users and accumulates hit data from single shots, rounds consisting of one or more hits detected during a user controlled period, and multiple rounds into records that provide long term training and performance information.
[0010] The present system allows users to gain audible feedback for hits on a defined target area. This eliminates the need to stop the range session to bring the target back to the user or for the user to walk down range to view target and in addition eliminates the constant delays experienced when viewing the target through the gun scope or spotting scope. Additional sensory feedback through sound greatly increases target shooter efficiency.
[0011] The target impact sensing system comprises or consists of a target with an impact sensor attached thereto, a wireless transmitter electrically connected to the impact sensor, a wireless receiver capable of receiving the wireless message with impact describing data from the transmitter and a software application for inputting data and parameters and providing an interface the transmitter and receiver. The receiver is capable of providing an impact describing audible message to a user. The impact describing audible message is interpreted from the impact describing data.
[0012] It is an object of this invention to provide an impact sensing target system which includes a small wireless impact or vibration sensor mounted on a target, with a transmitter.
[0013] It is an object of this invention to provide an impact sensing target system which includes a receiver which reports the sensor data to the shooter over headphones, ear buds or over a receiver such as an I-phone using a RF transmitter such as Bluetooth technology.
[0014] It is an object of this invention to provide an impact sensing target system wherein sensors are attached to selected areas on a vest to be worn by a paint ball competitor and wherein the impact of a paint ball or other projectile on a selected sensor causes a particular tone or other identifying signal to be transmitted to the headphones of the person who has been shot, to the person doing the shooting and others if so desired.
[0015] It is an object of this invention to provide an impact sensing target system including a plurality of individual targets of increasing size, individual sensors connected to each target, all sensors connected to a transmitter, and a receiver with headphones which identifies which target has been hit.
[0016] It is an object of this invention to provide an impact sensing target system wherein the sensor transmitter includes a small loudspeaker which creates a loud sound mimicking an exaggerated impact in the area of the target which has been hit by a projectile.
[0017] It is an object of the invention to sense impacts in different areas of a target and provide variable audible feedback which can be interpreted to determine the area or portion of a target hit.
[0018] It is an object of this invention to provide an impact sensing target system wherein the projectile is actually a beam of light from a laser gun, the sensor transmitter includes a small loudspeaker which creates a loud sound mimicking an exaggerated impact in the area of the target which has been hit by a laser beam and the receiver with headphones receives a message identifying which particular target was hit.
[0019] It is another object of the present invention to provide an software app for a phone, iPO, or other receiver wherein any desired sound can be selected or recorded or downloaded to the receiver to be played for the user upon receiving the signal from the RF sensor and transmitter.
[0020] It is another object of the present invention to provide for a sensor which may be applied to a small or large target to recreate a desirable selected sound which is not dependent upon accuracy to hit the sensor only vibrations received from the sensor mounted onto a target of selected size.
[0021] It is another object of the present invention to provide an software application, transmitter, receiver, and sensor to enable the duplication of a selected rifle caliber, or provide a volume of sound in accordance with the type or gun, or distance the target is from the shooter as well as the type of material comprising the target.
[0022] It is another object of the present invention to build a counter into the software application
[0023] Other objects, features, and advantages of the invention will be apparent with the following detailed description taken in conjunction with the accompanying drawings showing a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] A better understanding of the present invention will be had upon reference to the following description in conjunction with the accompanying drawings in which like numerals refer to like parts throughout the views wherein:
[0025] FIG. 1 shows a flow chart depicting the components of the algorithm;
[0026] FIG. 2 is a photocopy showing user selectable area of a “hit zone” shown in the rectangle ode to extend the view 20% using camera features to zoom in an enhance an image wherein the area of interest plus 20% fills the display;
[0027] FIG. 3 is a screen shot of an application running on a development ANDROID smart phone;
[0028] FIG. 4 is a screen shot of an application algorithm detecting real time bullet hits on target, coloring the hits, and producing sound feedback with each hit indicating detected hits, and user buttons to adjust sound, detailed text, increase aor decrease th user defined hits zone, and screen resolution adjustment;
[0029] FIG. 5 is a screen shot of an application algorithm detecting the most recent bullet hit and previous bullet hits on target;
[0030] FIG. 6 is a “round view” wherein the application display shows an end of a round in which the user can quickly and easily review all of the shots, inside hits and outside hits selectively in the “hit zone”;
[0031] FIG. 7 shows a screen shot displaying the hits, time and sequence of shots in a round including to display of shot analysis during a user defined period showing the shot sequence, time between each shot, shots inside or outside the defined hit zone, groupings, scoring options, and constructive feedback for better shot placement and groupings;
[0032] FIG. 8 shows a screen shot displaying the hits, time and sequence for a selected sequence whereby the application displays the elapsed time playback with the user controls allowing cycling through successive or previous shots for a more detailed analysis for a defined period utilizing arrows graphing show sequence, shots inside or outside of the hit zone, groupings, scoring options, and constructive feedback for better shot placement and/or groupings;
[0033] FIG. 9 shows a flow chart depicting the components of the algorithm in the Freestyle Mode;
[0034] FIG. 10 shows a flow chart depicting the components of the algorithm in Practice Mode;
[0035] FIG. 11 shows a flow chart depicting the components of the algorithm in Training Mode; and
[0036] FIG. 12 shows a flow chart depicting the components of the algorithm in Game Mode.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] A combination of software and hardware executing on a mobile device (smart phone, tablet) that monitors available inputs during firearm target shooting*, detects hits on targets, records all relevant hit data, indicates the hits to users and accumulates hit data from single shots, rounds and multiple rounds into records that provide long term training and performance information.
[0038] Users gain audible feedback for hits on defined target area without the need to stop range session to bring target back to user, user walk down range to view target or constant viewing through gun scope/spotting scope. Additional sensory feedback through sound greatly increases target shooter efficiency. The system can be used in any target shooting application including but not limited to large and small caliber rifles, pistols, revolvers, BB and pellet guns, airsoft guns, slingshots, etc.
[0039] As set forth in the diagram of FIG. 1 , the instant system comprises the following components including a group of primary input devices including mobile devices such as a digital camera with zoom lens, an accelerometer, microphone, and touchscreen (for selecting area of interest), providing data for the process input hit detection algorithm.
[0040] As best illustrated in FIG. 2 , the user's selection of an area of interest whereby the user selectable area of the “hit zone” can be defined though various methods including camera view, touch screen defining a specific area on view of fiducials applied to target, all to represent size and shape of a desired hit zone. Optical and digital zoom can be used to enhance image size and resolution. FIG. 2 shows the user selectable area of a “hit zone” set forth in the rectangle mode to extend the view 20% using camera features to zoom in an enhance an image wherein the area of interest plus 20% fills the display.
[0041] Auxiliary inputs include a remote sensor attached to the target or near a target consist of a digital camera or accelerometer which also provides data for the process hit detection algorithm.
[0042] User preferences selected from devices such as a microphone, touchscreen device and saved profiles thereon provide additional data forth process detection algorithm. The user may enter data such as right handed or left handed shooter, distance to target, firearm make/model, caliber, bullet weight, ammo type/brand, defined hit zone, invalid hit detections, missed hit detections, environment (indoor/outdoor-temp, weather), etc.
[0043] The process inputs provide the data for the hit detection algorithm which considers the user preferences. The processing for this application is primarily image processing augmented with cues from an accelerometer, a microphone, and a touchscreen device for improved accuracy. Custom developed learning algorithms, BAYESIAN algorithms and generic algorithms increase accuracy and repeatability of hit recognition. Alternative modes support detection based on remote sensors near or attached to the target can perform low level analysis before transmitting summarized result data to the mobile device.
[0044] As shown in the screen shots depicted in FIGS. 3-5 , a “Single Hit” output provides an a audio which sends alerts to the user via mobile device speaker or attached BLUE TOOTH headset. An on screen text, graphic overlays on the target area, and camera flash can be used in long range applications by utilization of a reflective sticker on the target to reflect the reflection back to the user and detection device. In addition, a mirror on the phone may be used to reflect the flash back to the user's detection device. The screen shot in FIG. 3 sows the application running on an ANDROID phone, wherein the screen shot shown in FIG. 4 shows the detected hits and user buttons for adjusting the sound, detailed text, deceasing zone, increasing zone and change of screen resolution. The application algorithm detects real time bullet his on the target coloring the hits and production sound feedback with each hit. The most recent hits and previous hits can be detected, shown, or replayed whereby the algorithm detects the bullet his on the target. The most recent hit maybe a selected bright color with the previous hits displayed in a different shade or dim color. Sound feedback is user defined and varies depending on where the bullet hits the target.
[0045] As shown in FIGS. 7-9 , the “Multiply Round Output” includes the graphic overlay on the target area, training suggestions based on shot analysis, and the overall round score. For instance in FIG. 7 the application display shows hits inside and outside of the target and the end of round for a user defined period in which the user can quickly and easily review all of their shots which may be color coded to display the shots inside the defined “hit zone” and outside of the defined “hit zone”. FIG. 8 illustrates a screen shot wherein the sequence, for example (hit #7 at a time of 2.9 seconds), is shown as “7-2.9” in a first window on the screen. Illustrations depict a second window showing the outside hit shots and inside hit shots by varying graphics, a third window shows the Round Suggestions such as to “take more time between shots”, and the fourth window displays the round score, for example: 1) In Hits: 6×2=12, 2); Out Hits: 4×1=4; 3) Groups; 2×3=6; and 4) Total: 22. The application shown in FIG. 8 displays shot analysis during the user defined period, showing shot sequence, time between each shot, shots inside or outside the defined “hit zone”, groupings, scoring options, and constructive feedback for better shot placement and groupings. The display depicted in FIG. 9 , provides a display of elapsed time playback with user controls allowing cycling through successive or previous shots for more detailed analysis. The display shows the shot analysis during the user defined period utilizing arrows graphing shot sequence shown as broken arrow lines or solid arrow lines based on the time between each shot. The shots inside or outside of the defined hit zone, groupings, scoring options and constructive feed back for better shot placement and/or groupings can be illustrated on the display as well. The present application provides time/sequence arrows, outside hits, inside hits, grouping, playback controls for stepping through graphics for each hit, round suggestions, and round score tallies, the long term score averages, low scores, high scores, suggested areas of training, suggested training exercises, cataloguing of range rounds, and the accuracy of firearms with respect to ammo brands, caliber, bullet weigh, etc.
[0046] The method of using the present application involves the following steps:
[0047] In the first step, the user chooses between built-in sounds for hit detection. Optionally, the user purchases additional sounds—plink, cannon, bottles, ricochet, large caliber, small caliber, explosions, voice commands/feedback, numbers, or combinations thereof.
[0048] The user selects how the sounds will vary between hits to indicate successive hits within a target proximity, hit in new area, hit with short time interval. These effects can accumulate, for example successive hits in the same area within a 5 second interval may produce a sound that continues to increase in pitch.
[0049] Another step involves selecting how the sound series may transition into other sounds, for example “plink, plonk, plunk, BOOM”. The sounds can indicate distance to center of the target based on pitch, using different sounds or via voice prompts for example “1 inch from center, high, right”).
[0050] The user may elect the step to display and highlight the most recent and past hits in a round with a bright color or the display can highlight earlier (previous round) hits with a different color.
[0051] The user may elect to control some variables to improve the accuracy of hit detection such as caliber, distance to target, region of interest in image, blur, focus, zoom, manually add missed detections, delete invalid detections, and save images of rounds to metadata to enable simulated round playback. The inputs by the user can be utilized by the application to improve the hit detection for the user session or for all user sessions on all devices by transmitting the environment dat back to a centralized server(s) for analysis.
[0052] The user may elect the step to remotely control the beginning round, end round, and other actions via Blue tooth controls manually or by voice activation controlled via Blue tooth or device microphone.
[0053] The user may elect the process of applying a graphic overlay on the target area during a round including additional details indicating timing intervals, sequence of shots, cluster analysis results, out of zone hits, etc. The graphic overlay utilizes text, arrows, various hit color schemes and other graphic indicators.
[0054] For example, during a round the combined result view may use arrows to create a link from a previous shot to the next shot, the arrow can be colored or dashed according to the period of time between the two hits. Hits detected out of the zone will be linked in this chain but will be a selected color such as red while hits in the zone are another selected color such as green. All sequential hits that fall within a user defined grouping (or cluster) limit may have additional rings of another selected color such as orange around the center color. More indicators can be displayed as needed using a set of user controlled check boxes.
[0055] During a round a single result view allows the user to toggle through individual hit analysis features. The user may select “History/Sequence” and the hits may be linked with arrows or use color shading to indicate the hit history. The first hit can be black while the last hit is bright green. All hits between will be shaded using a gradient/interpolation calculation.
[0056] During a round a single result view can be toggled to grouping and the user can select two points on the display to specific their desired grouping extents. The display will locate one or more groups on the target and shade hits in groups with different colors. If no grouping size is detected, the display will use either the last grouping size inputs or a cluster analysis algorithm.
[0057] During a round a single result view can be toggled to target zone mode. The user may specify a target zone or a previous target zone may be used by default. The colors for in zone and out of zone hits will be different.
[0058] During a round a single result view can be toggled to timing mode. Text and/or arrow indicators will specify the amount of time between hits and the user may adjust slider bars or other input field to designate thresholds. All hits within the first threshold range may be green, middle range shown in yellow, third range as red.
[0059] For a round, a total weighted score can be displayed to the user. This score is a result of several different scoring categories each of which can be adjusted by the user. Standardized and/or preset scoring rules can be used or custom rules can be defined. The scoring categories can include: any hit, in zone hit, distance to center (defined), time between hits, sequence is line, grouping, sequence is triangle, and combinations thereof. For each category, preset thresholds and limits may be used or the user may adjust the values. For the total score, preset weights may be used or the user may adjust the values.
[0060] Users can select any number of images as a “virtual target” overlay such as a deer, moose, pumpkin, zombie, dinosaur, or other desired target. The images depicted may be controlled by a holder of the copyright, other ownership of the images, or by state or federal law.
[0061] Configurable options apply across most aspects of the product. The user may enter a settings panel to set thresholds, zones, caliber, distance, color choices, sound preferences, etc. These will be saved and used during shooting practice.
[0062] Choosing some settings will allow the user to adjust the hit detection algorithm. Choosing caliber, projectile weight, and distance will adjust the behavior of the hit detection algorithm in its criteria for hits and its usage of various image processing routines (image stabilization, image blurring, etc).
[0063] Adjusting the distance will also allow the user to control the audio/visual delay for hit detection. Choosing a longer distance can add the audio delay associated with the speed of sound.
[0064] Reflective dot sticker attached to target (top corner, bottom corner, etc). Individual hits in defined target zone will cause the camera to use the flash and the light will be reflected from the sticker. Multiple hits can cause the camera to flash patterns of lights. Shooter can receive both visual and audio feedback.
[0065] For a nearby cue, a mirror next to or attached to phone/tablet will reflect camera flash back to user when individual hits in defined target zone are made. Multiple hits can cause the camera to flash patterns of lights. The shooter can receive both visual and audio feedback.
[0066] The application can also determine the areas of interest on targets without user input if specially designed targets with fiducials are used. The algorithm can detect the fiducials and their positioning and match them to a database which will identify the mode, target type, game, etc. for the application to support for this session.
[0067] The following examples describe preferred embodiments of the invention. Other embodiments within the scope of the claims herein will be apparent to one skilled in the art from consideration of the specification or practice of the invention as disclosed herein. It is intended that the specification, together with the examples, be considered exemplary only, with the scope and spirit of the invention being indicated by the claims which follow the examples. In the examples all percentages are given on a weight basis unless otherwise indicated.
Mode Examples:
[0068] The present invention provides various modes of uses which include selected features for particular applications.
Freestyle Mode
[0069] The freestyle mode allows shooter to freely “plink” at targets while gaining audio feedback on hit in designated target area. Customizable sound feedback at the discretion of the user. It also allows shooter to utilize any number of the specific features within the “features list” or choose no analytics and just shoot for fun.
Practice Mode
[0070] The practice mode allows shooter to provide detailed inputs (firearm make/model, caliber, bullet weight, ammo brand/type, target distance, designated target area, etc) with the algorithm capturing data for post shot, round and multi-round analysis and feedback. Audio feedback on the shooter such as jerking the trigger, left hand, over gripping—right hand, breaking the wrist up—left hand; are available as suggestions.
Training Modes
[0071] The training modes include the moving target mode wherein the voice audio commands direct where to hit such as “top left”, “bottom right” with increasing/adaptable speed levels. The stress mode provides various background sounds to simulate shooting under duress. The timed mode provides sounds announcing the start and end or a round for timed tactical training.
Game Modes
[0072] With or without target displays, the user may choose to play games such as “tic-tac-toe”, “smiley face”, “Simon says”, or custom branded modes such as HICKOK45 Mode. For instance, “tic tac toe” may use a custom printed target. The game may be single player or versus a computer. Single player wins each time three (3) hits are made in the grid horizontally, diagonally or vertically. “Smiley face” allows the image processing application to judge the quality of a minimum of 5 shots to form a smiley face. “Simon says” provides a verbal list of shots on a printed grid. A 4×4 grid may be numbered 1 through 16. The voice prompt will command “9—8—2—15” and the user must hit these numbers in sequence. Grid size, command length and other variables can be adjusted by the user. One mode within the branded HICKOK 45 game set is a mode using a custom target representing various metal targets, glass targets, clay targets and fruit. Hits will be detected and the audio will produce the corresponding hit sounds (glass breaking, metal plinks, etc). This mode may feature custom audio from an actor suggesting targets or may be freestyle.
[0073] The foregoing detailed description is given primarily for clearness of understanding and no unnecessary limitations are to be understood therefrom, for modification will become obvious to those skilled in the art upon reading this disclosure and may be made without departing from the spirit of the invention and scope of the appended claims. Accordingly, this invention is not intended to be limited by the specific exemplification presented herein above. Rather, what is intended to be covered is within the spirit and scope of the appended claims. | A system for sensing the impact of a bullet on a target and remotely reporting the successful impact to the shooter by means of a signal transmitted from a sensor transmitter to a receiver incorporated with headphones, ear buds or an “Smart phone”, tablet or other device with WIFI and/or Blue tooth capability. The sensor includes a wireless transmitter and a impact/vibration sensor such as a piezoelectric sensor. The target impact sensors can be used with various stationary targets such as metallic, plastic, film, or paper targets, but can also be used on movable targets such as body armor or removable patches worn by players in mock warfare or games such as paint ball competition to effect audible signals. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
Reference is made to and priority claimed from U.S. Provisional Application Ser. No. 60/005,396, filed 6 Oct. 1995, entitled ACTUATOR WITH SINGLE SURFACE-FIELD MOTOR.
FIELD OF THE INVENTION
The present invention relates to an improved optical recording actuator for driving a lens holder in focus and fine tracking movements.
BACKGROUND OF THE INVENTION
Focus/tracking actuators are used in optical disc recording and reading devices to control the lens position relative to the rotating disc. Both focus (the distance between the lens and the disc surface) and tracking (the correct radial position of the lens so as to read or write a single track at a time) must be maintained. This is necessary to compensate for unavoidable warpage of the disc, spindle errors, and other mechanical and optical imperfections. The focus and tracking motions of the actuator are controlled by a servo system.
The actuator servo system typically includes one or more electromagnetic motors to generate the forces necessary to move the lens holder, and one or more position sensors to provide feedback to control the motion. Each electromagnetic motor comprises a coil or coil assembly and a permanent magnet, with one or the other being mounted to the moveable portion of the actuator. Each position sensor comprises a light source, an optical slot or flag, and a photosensitive detector.
The use of a single motor, located away from the center of gravity of the moving mass of the actuator, would normally be expected to cause dynamic problems. A single, unbalanced motor would typically excite rotational resonances of the actuator due to the moments induced. These inertial moments are caused by the distance between the line of action of the motor force and the center of gravity of the moving portion of the actuator. This is one reason that existing optical recording actuators typically use coils wrapped around the lens holder, or surface-field motors used in balanced pairs. While reducing torsional resonance, however, these motor configurations limit the optical paths available for a designer to pass a beam from the optical head to the lens. The writing/reading beam from the optical head therefore typically enters the actuator from below; that is, from the side of the actuator opposite the disc. This limits the compactness of the reader/writer system.
Motors with wrap-around coil configurations often include a section of unsupported wire coil. The flexibility of the unsupported portion of coil causes additional unwanted mechanical resonances. These resonances degrade actuator and system performance, require more complex and costly servo control systems, and limit the frequency response of the actuator, thereby limiting the system read and write speed.
Sensors providing positional information to the servo system typically utilize a light source, such as an LED, that is separate from the source of the beam used to read and write information on the disk. An image is created in this separate beam using a slot or flag mounted to the lens holder, and is projected onto a photosensitive detector. These components are often mounted on the side of the lens holder, adding to its size and mass.
It is necessary to limit the travel of the lens holder in both the focus and tracking directions in order to avoid overtravel, which may damage components. This is especially true in a power-off condition during transport. Stops are typically added to the base and the lens holder to prevent overtravel.
SUMMARY OF THE INVENTION
The actuator of the invention is driven by a single surface-field electromagnetic motor with three or four poles. The term "surface-field motor" as used herein is defined as a motor with a multiple pole magnet and a thin coil set arranged on opposite sides of a gap having the shape of a planar, curved or angled surface. Similarly, "surface-field magnet" and "surface-field coil" refer to components configured for use in a surface-field motor. In a preferred embodiment of the present invention, the multiple pole magnet of the actuator motor is attached to the lens holder, which is the moving portion of the actuator. The lens holder is supported by four flexures. The use of a single motor leaves open three sides of the lens holder, allowing the optical head to be on the same level as the actuator, with the beam entering the actuator between the four flexures. The beam is then turned by a fixed mirror or prism, or other turning means, and enters the actuator lens after this turn. It is then focused by the actuator lens onto the disk.
In another embodiment of the invention, a beam splitter is used to turn the beam, and a portion of the beam is allowed to pass through the beam splitter. An image is created in this portion of the beam by an aperture in the magnet structure. This image passes through a clearance hole in the coil assembly, and strikes a photosensitive detector mounted behind the coil structure. The outer surfaces of the beam splitter, in conjunction with molded internal surfaces of the lens holder, can be used as stops to limit travel at both extremes of each of the focus and tracking coordinates.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of one embodiment of the optical actuator of the present invention;
FIG. 2 is a partial cut-away side elevation view of the actuator of FIG. 1;
FIG. 3 is a schematic side sectional view of a lens holder assembly of the present invention, showing the orientation of magnetic flux lines and generated forces;
FIG. 4 illustrates a coil/magnet configuration having four square coils and four triangular magnets;
FIG. 5 illustrates a coil/magnet configuration having two square coils, one triangular coil and square and rectangular magnets;
FIG. 6 illustrates a coil/magnet configuration having square coils and square magnets;
FIG. 7 illustrates a coil/magnet configuration having two square coils and three triangular magnets;
FIG. 8 illustrates a bridge circuit for an actuator having a tilted coil/magnet configuration;
FIG. 9 illustrates a coil/magnet configuration which can be used in conjunction with the bridge circuit of FIG. 8;
FIG. 10 illustrates a partial cut-away side elevation view of one embodiment of the actuator of the invention; and
FIG. 11 illustrates a perspective view of a lens holder and beam splitter of one embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown in FIGS. 1 and 2, the actuator 1 of the present invention comprises a moving lens holder assembly 10 connected to a base 4 by flexures 5a-5d. The base 4 is shown schematically in FIG. 1 in order to simplify the view. Also attached to the base 4 is the coil set 55 consisting of round coils 31. In FIG. 1, the attachment of the coil set to the base 4 is not shown, and the gap G between the coil set and the lens holder assembly 10 has been exaggerated for clarity.
The lens holder assembly 10 comprises a lens holder 11, a lens 12 mounted in the lens holder 11 and a quadrapole magnet 41 consisting of four square magnets 41a-d with flux return plate 42. The lens holder can be injection molded from a high modulus plastics material such as Vectra® liquid crystal polymer. A vertical flange 15 extends downward from the front of the lens holder 11, adding rigidity to the lens holder 11; the remaining sides of the lens holder 11 are left open. As shown in FIG. 2, this configuration allows a read/write beam 100 to pass through the lens holder 11, through the lens 12, and onto an optical disc 6 to read or write information.
Returning to FIG. 1, the lens holder 11 is suspended by four flexures 5a-5d. The flexures act collectively as a torsional spring, allowing the lens holder 11 to move vertically for focusing and laterally for tracking. Because the flexures are not parallel, the lateral motion is not pure translation but rather a rotation about a line between the virtual intersections of the flexures. This flexure angle also results in improved actuator dynamics and increased robustness to assembly tolerances. The flexures 5a-5d shown in FIGS. 1 and 2 are constructed of a medium flexibility wire attached in cantilever supports to the base 4 and the lens holder 11. The wires bend in response to forces applied to the lens holder 11, permitting the lens holder 11 to translate in the focus and tracking directions. Alternatively, injection molded plastic flexures (not shown) could be used. Each plastic flexure has two flexible segments which allow for focus motion, and two flexible segments which allow for tracking motion.
The single, surface-field electromagnetic motor assembly 40 comprises a quadrapole magnet 41 attached to the lens holder 11, and a coil set 55 attached to the base 4. By using the motor in an inverted (moving magnet) configuration, the resultant forces on the lens holder 11 can be located at a point proximate or coincident with the center of gravity of the lens holder assembly 10, as described below. This greatly reduces or eliminates inertial moments normally expected with a single offset motor. Further, the use of surface-field moving magnets eliminates the resonance problems typically resulting from unsupported segments of wire coils. In addition, no flexible leads are required to carry current to the moving part of the actuator.
As shown in FIG. 2, the set of coils 55 is attached to a bracket 51 which is secured to the base 4. In accord with the invention, the set of coils 55 is arranged in a surface configuration which, advantageously, can be relatively thin and compact. The shape of the coils in the coil set 55 can be square, rectangular, round, oval, triangular or any other appropriate shape to enhance the performance of the electromagnetic motor, as long as a surface-field arrangement is maintained. The coil set may be constructed using conventional wound coils or, due to the flattened nature of the coil set, printed circuit coils can be used which can be fabricated by either thin film or thick film processes. As used herein, "coil set" or "set of coils" includes, and is not limited to, a surface-field construct comprising conventional wound coils or printed circuit coils.
In the configuration where the coils are attached to a piece of printed circuit board, the resulting assembly can be manufactured in an automated assembly cell to minimize cost. Such a part can be supplied by the coil manufacturer as a subassembly.
A coil flux return plate 53 (FIG. 2) can be located behind the set of coils 55 to decrease the electromagnetic motor's sensitivity to the distance from the quadrapole magnet 41 to the plane of the coil set 55 as well as increase the magnetic flux in the gap.
The set of coils 55 is attached to a substrate or integrated into a structure, preferably with an adhesive, in the configuration shown. The substrate can be the bracket 51, the coil flux return plate 53 or an intermediary material such as a printed circuit board containing circuit traces for appropriately interconnecting the coils and providing an attachment point for the servo power supply used for controlling the forces developed by the electromagnetic motor.
The set of coils 55 is placed facing and in close proximity to the quadrapole magnet 41. The magnet structure has a planar, curved or angled surface shape and has alternating areas of north and south poles with a minimum of three poles. FIG. 1 illustrates a motor structure having four round coils 31 facing a quadrapole magnet 41 with four square magnetic poles 25. An alternative configuration consists of four square coils with a quadrapole magnet 41 (having two north and two south poles) as shown in FIGS. 4 and 6 which illustrate alternative embodiments of such a configuration. In FIG. 4, the square coils 19 face a quadrapole magnet 41 having triangular magnetic poles 21. In FIG. 6, the square coils 19 face a quadrapole magnet having square magnetic poles 25.
As shown in FIGS. 1 and 2, the quadrapole magnet 41 is attached to the outer surface of the vertical flange 15 of the lens holder 11. The structure can be made either by assembling appropriately polarized pieces of permanent magnet or by magnetizing a single piece of magnetic material in the desired configuration using known technology. The back side of the quadrapole magnet 41 can be equipped with a flux return plate 42 consisting of a steel or other soft magnetic material that increases efficiency by increasing the magnitude of the magnetic flux and thus the force developed by the electromagnetic motor for a given current.
The configuration of the quadrapole magnet 41 is not limited to the configurations illustrated. Other configurations include, for example, a round magnet, or the intersections between the magnetic poles can be arranged from corner to corner rather than from side to side by using triangular magnetic poles, as shown in FIG. 4. FIG. 5 illustrates a 15 coil set having two square coils 19 and one triangular coil 27. The coil set faces a quadrapole magnet having two square magnetic poles 25 and two rectangular magnetic poles 29.
FIG. 7 illustrates two square coils 19 facing a magnet structure having three triangular magnetic poles 21. An electromagnetic motor having two coils and three magnetic poles is not capable of independent control of the torque exerted in the plane of the coil set since that would require three degrees of freedom and there are only two control variables (currents or length of wire) with two coils. Those skilled in the art will understand that other combinations of coils and magnetic poles can be used in accord with the invention in addition to those shown in FIGS. 1-7.
The intersections of the north and south pole areas are aligned along the diagonal centerlines of the coils in the case of square or rectangular coils, across a diameter in the case of 35 round coils, or from the midpoint of the base to the right angle corner in the case of right isosceles coils. The center point of the quadrapole magnet 41 preferably is aligned with the center of the set of coils 55 in the case with four coils and four magnetic poles.
The attachment of the set of coils 55 to the bracket 51, and of the quadrapole magnet 41 to the lens holder 11, can be made by any conventional means, such as glue, bonding, or screws. Other means will be apparent to those skilled in the art. A set of cooling fins 52 extend from the surface of the bracket 51 opposite the coil set 55 to conduct heat away from the coils. A suitable physical separation should be maintained between the coils and the magnets. The separation can vary depending on the arrangement chosen. The preferred separation is within the range of 0.1 mm and 0.5 mm.
As discussed in more detail below with reference to FIG. 3, when current is supplied to any one of the coils in coil set 55 a resultant force is developed by the motor on the lens holder assembly 10. The resultant force F r is directed through a point offset from the center of the coil. The force lies in a plane parallel to the plane containing the coil sets 55 and orthogonal to the plane separating the multiple pole magnetic structures 25. If the direction and magnitude of the current to the individual coils is appropriately selected, then forces can be developed in either the focus or the tracking directions. In addition, if the amount of current is different, or even reversed, between opposite coils within each coil set 55, a torque can be developed about the mid-point of the coils. The same effect can be produced by maintaining a constant current and varying the number of turns in the opposite coils.
The electromagnetic motor can be constructed with the coil set 55 and the magnet structures rotated 45 degrees, or any other desirable angle about the axis through the center of the coils set orthogonal to the surface of the coil set 55, to provide a lower height actuator. This arrangement lowers the height of the electromagnetic motor but increases the complexity of the servo system since the forces generated by the coil set 55 would not be singular in the focus and tracking directions. This potentially would increase the complexity of the servo system, which would now need to quantify the accelerations required in the focus and tracking directions and solve the equations of motion for the oblique forces that are developed in the coils. An alternative approach, which does not significantly increase the servo complexity, is to use a coil control bridge circuit, such as that shown in FIG. 8. The bridge circuit can be implemented with the coil/magnet arrangement illustrated in FIG. 9. The bridge circuit distributes the current supplied by the servo control system to the coils in such a way that the servo need only supply direct focus and tracking control currents.
FIG. 3 is a partial sectional view of the actuator in plane III-III of FIG. 1. The square magnetic poles 25 of quadrapole magnet 41 produce magnetic flux 43. The round coil 31 is shown in section as it lies in the magnetic field (for clarity, only one focus coil is shown; the same principle applies to the other focus coil and the tracking coils). The forces generated on each part of the active coil segments are perpendicular to both the magnetic flux lines 43 and the coil current, which travels into and out of the plane of FIG. 3. These forces are shown by arrows F 1 and F 2 . The resultant sum F r of the two forces shown acts vertically at the intersection of F 1 and F 2 , along a line of action that is within or behind the actual magnet structure. The exact location of the line of action of F r is controllable by varying the magnet structure geometry, the coil size and the coil location. The location of the center of gravity of the lens holder assembly 10 can similarly be controlled by the design of the lens holder 11 and the location and size of the quadrapole magnet 41 and of the flux plate 42, if used. By manipulating these parameters, the effective line of force F r can be located at, or near, the center of gravity of the moving portion of the actuator. This results in the reduction of dynamic moments, reducing spurious resonance in the actuator frequency response.
By using a single motor assembly fewer parts are required, reducing cost and assembly time, and increasing reliability. At the same time, dynamic performance is good because there are no coils attached to the moving assembly to cause resonances, and the force is applied at or near the center of gravity of the moving portion of the actuator.
The moving magnet motor does not require current to be carried to the moving part of the actuator. Therefore there is no need for flex circuits or flexible wire leads. This reduces cost and complexity and increases reliability and life.
As best shown in FIG. 2, the use of a single motor assembly 40 at one end of the lens holder 11 allows for the laser assembly 101 to horizontally direct the read/write beam 100 into the lens holder assembly 10 between the flexures 5a and 5b. The beam is turned by a fixed mirror or prism 102, or other turning device mounted to the base 4 within the lens holder 11. These components can all be mounted at or near the same distance from the optical disk 6. Positioning the laser assembly and the turning device within the Z location occupied by the lens holder 11 allows for smaller system packaging. This compact configuration has improved structural and thermal stability and therefore higher performance and less sensitivity to thermal and mechanical stresses.
In the embodiment of the invention shown in FIG. 10, a portion of the read/write beam 100 is utilized in conjunction with an optical position sensor 150 for measuring the deflection of the lens holder assembly 10 in the focus and/or tracking directions. Information from the position sensor is used in the feedback control of the motor assembly 40.
A cubic beam splitter 110 functions as a turning device to reflect most of the read/write beam 100 (approximately 95% in a currently preferred embodiment) upward through the lens 12 for reading or writing information to the optical disk (not shown). The transmitted portion 115 of the read/write beam 100 continues in a straight path through the cubic beam splitter 110 and the motor assembly 40, and strikes an optical position sensor 150 as described below. The beam splitter comprises a triangular turning prism 111, a triangular correction prism 112, and a partially reflective surface 113 sandwiched between the prisms. This known configuration substantially eliminates the effect of the index of refraction of the turning prism on the path of the transmitted portion 115 of the read/write beam 100.
An image producing means such as masking hole 140 in the quadrapole magnet 41 creates an image in the transmitted portion 115. This image strikes the optical position sensor 150, which is rigidly mounted to the base 4 through bracket 51. A hole 141 in the flux return plate 42 provides a path for the transmitted portion 115. Clearance hole 142 in the coil flux return plate 53 and the bracket 51 provides a path for the image created by masking hole 140 in the quadrapole magnet 41, and provides clearance for motion of the image as the lens holder 11 deflects. While in the current preferred embodiment the magnet structure is attached to the moving lens holder 11, those skilled in the art will recognize that the beam splitter can also be used in an actuator with the coil assembly attached to the lens holder 11, and with the masking hole in the coil assembly.
In operation, the transmitted portion 115 of read/write beam 100 continues in an essentially straight path through the cubic beam splitter 110. Because the masking hole 140 is a part of the lens holder assembly 10, the position of the image of the hole on the optical position sensor 150 moves with the lens holder position.
The optical position sensor 150 is preferably a quad-cell detector capable of measuring the position of the image in both the tracking and focus directions, such as a multi-element silicon diode Ser. No. S4349 marketed by Hamatsu Corp. Alternatively, a device such as a position sensitive detector, Ser. No. S1743, also sold by Hamatsu Corp., could be used. If the measurement of motion in only one of the tracking and focus directions is required, a single axis detector such as Hamatsu Ser. No. F3273-4 could be used.
By utilizing a portion of the read/write beam 100 for sensing the position of the lens holder 11 with respect to the base 4, there is no need for an additional illumination source to provide a measurement beam. Further, no separate masking flags or apertures are required because the masking hole 140 is an integral part of the quadrapole magnet 41. This reduces cost and reduces the mass of the moving portion of the actuator. Because the components of the position sensing system are contained largely within the envelope of the actuator, the package remains compact.
In a preferred embodiment of the invention, the cubic beam splitter 110 is used in conjunction with surfaces molded in the lens holder 11 to provide travel stops in the focus and tracking directions. As shown in FIG. 11, lens holder surfaces 11a and 11c (hidden),stop against corresponding beam splitter surfaces 110a and 110c, preventing overtravel in the tracking direction. Similarly, lens holder surfaces 11b and 11d stop against the beam splitter surfaces 110b and 110d, preventing overtravel in the focus direction. By utilizing the surfaces of the beam splitter as stops, the need for special stop surfaces fixed to the base 4 is eliminated, reducing cost.
The embodiments described herein are made without limitation. Other embodiments in addition to those illustrated and described herein will be known to those skilled in the art. Therefore, the invention is limited only by the claims.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.
______________________________________Parts List______________________________________4 base5a-5d flexures6 optical disc10 lens holder assembly11 lens holder11a-d lens holder surfaces12 lens15 vertical flange19 square coils21 triangular magnetic poles25 square magnetic poles27 triangular coils29 rectangular magnetic poles31 round coils40 motor assembly41 quadrapole magnet41a-d multiple pole magnet structure42 flux return plate43 magnetic flux lines51 bracket52 cooling fins53 coil flux return plate55 coil set100 read/write beam101 laser assembly102 prism110 cubic beam splitter110a-110d beam splitter surfaces111 triangular turning prism112 triangular correction prism113 partially reflective surface115 transmitted portion140 masking hole141 hole142 clearance hole150 optical position sensor______________________________________ | A lens actuator for an optical disc storage device including a base; a lens holder assembly movably mounted to said base; said lens holder assembly comprising a lens holder with a single surface-field magnet and a lens mounted thereon; a single surface-field coil set mounted to said base parallel to and proximate said surface-field magnet; whereby a current introduced in a coil of said coil set produces a net magnetic force having a resultant line of action passing through said lens holder assembly. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to apparatus for coating a substrate such a paper or plastic webbing.
2. Description of the Related Art
Two important techniques are used today in the art to apply a coating to a substrate. Each, however, has its own drawbacks. In one coating technique, a substrate is passed underneath a knife blade Positioned generally perpendicular to the path of travel of the substrate. A coating is applied with a greater thickness to the substrate, upstream of the knife blade. The material is typically much thicker than the desired final coating. The bottom, working edge of the knife blade is spaced a precise distance above the surface of the webbing to be coated, to meter the coating while setting a maximum thickness limit for the coating downstream of the knife blade. Also, the coating is spread onto the substrate surface by the knife blade, a feature which is sometimes relied upon to impart a desired finish to the coating. It is generally preferred that the coatings applied in this Manner are continuous and unchanging throughout the length of a production run, that is, from one section of substrate to another.
As those familiar with the art are aware, the knife blade application process offers significant advantages such as applying multiple coatings to a single substrate, but is subject to streaking which must be carefully monitored during a production run. The problems considered here are associated with small particles present in the coating material, which are of a size approaching the gap between the knife blade and the webbing surface. The knife gap in commercial applications is typically very small, of the order of 1 to 2 mils. The particles may comprise airborne contaminants, or perhaps paper fibers which are present in the environment. The particles may also comprise constituents of the coatings. Paint formulations typically include a liquid vehicle to which one or more colorants are added. These colorants often take the form of solid particles which are finely ground and dispersed throughout the paint base. Different colors and types of coatings have different coloring agents exhibiting a fairly wide variety of particulate sizes and characteristics. Some colors and coating types are especially prone to having larger size particles in the liquid suspension. Coatings containing these particles are applied to the substrate immediately upstream of the knife blade and are made to pass underneath the knife blade due to the momentum of the substrate. If the particles are of a size on the order of the gap between the knife blade and the substrate, an imperfection in the coating, which frequently is visible to the unaided eye as a streak, will result. In some applications, it is important that the coating be uniform throughout a relatively long production run. For example, in the manufacture of color samples, a substrate many feet in length will be coated with one or more stripes of different coating materials, and later divided into swatches or "chips" on the order of a inch square in size. Very often, a coating imperfection due to an overly large particle passing underneath a knife roller will be of a size sufficient to spoil several chips. While the coatings can be subjected to unusual preprocessing steps such as filtration or ultra-filtration techniques, these steps are of themselves costly to operation and may prove commercially impractical for some jobs.
In another popular technique used today, a series of rollers apply coating to a substrate. A primary roller is partly immersed in a coating material and transfers the material to a series of downstream rollers, which in turn, convey the material to a substrate. Roller coating devices can deliver a good quality coating across the width of a web, but cannot simultaneously apply multiple coatings to the same substrate, as can be done with the knife coating process.
SUMMARY OF THE INVENTION
It is an object according to the present invention to provide a simplified apparatus which overcomes the above-stated deficiencies while combining the advantages of knife coating and roller coating techniques.
A further object according to the present invention is to use knife coating techniques to simplify multicolor coating of a substrate while eliminating streaking in the finished product.
Yet another object according to the present invention is to reduce or eliminate static charges in the coating process.
These and other objects which will become apparent from studying the appended description, taken in conjunction with the drawings, is provided in an apparatus for coating a webbing, comprising:
a feed roller about which a webbing is at least partially wound;
means for rotating the feed roller;
a transfer drum adjacent the feed roller, having an outside surface;
means for rotating the transfer drum;
supply means for supplying a coating material to the outside surface of said transfer drum;
a doctor blade adjacent the transfer drum surface, downstream of said supply means for limiting the thickness of the coating material passing in a downstream direction underneath the doctor blade; and
locating means for locating said feed roller adjacent the outside surface of said transfer drum so as to bring webbing wound about said feed roller into contact with the coating material carried on the transfer drum to thereby transfer the coating to the webbing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of coating apparatus according to principles of the present invention;
FIG. 2 is a plan view thereof;
FIG. 3 is a fragmentary side elevational view thereof;
FIG. 4 is a fragmentary perspective view thereof;
FIG. 5 is a fragmentary elevational view showing the roller adjustment of FIG. 4;
FIG. 6 is a fragmentary cross-sectional view taken along the line 6--6 of FIG. 5;
FIG. 7 is a fragmentary perspective view of a coating application station; and
FIG. 8 is a fragmentary schematic view, taken on an enlarged scale, showing the printing rollers in greater detail.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and initially to FIGS. 1-4, coating apparatus according to principles of the present invention is generally indicated at 10. The coating is applied to a webbing substrate 12. A roll 14 of the webbing is mounted on frames 16 at the upstream end of the apparatus. The webbing roll 14 and supports 16 are located at a webbing supply workstation, generally indicated at 20, which is located at the upstream end of apparatus 10. Rollers 22, 24 guide and tension the webbing which is fed to a coating workstation generally indicated at 30.
As will be seen herein, the coating is applied to webbing 12 at workstation 30 and is then fed to a drying workstation generally indicated at 32 which has an open, upstream entrance end 34. The webbing is supported by a series of rollers 36 as it passes through an enclosure 38. Suitable drying means may be located within housing 38, and preferably both a heat source and forced air means are used to accelerate the drying time of the coating such that the coated webbing may be continuously wound about a storage roll (not shown).
Coating station 30 comprises a pair of rollers including an upstream, transfer drum or roller 40 and a downstream feed or backup roller 42. The webbing 12 is passed over a series of tensioning rollers including rollers 46, 48 shown in FIG. 1, so that the webbing enters the nip between rollers 40, 42 from below, passing above roller 42 toward the drying workstation 32, as indicated by arrow 50.
Preferably, the rollers 40, 42 are aligned with their central axes generally perpendicular to the direction of travel of webbing 12. The rollers 40, 42 are preferably of similar length and are aligned parallel to one another and spaced so that their outer surfaces are either very close to one another or engage one another with a preselected pressure, as indicated in FIG. 3, for example. In the preferred embodiment, the transfer roller 40 is preferably made of steel or other incompressible hard material while backup roller 42 has a steel core covered with an outer compressible, preferably rubber covering.
A segmented tray 56 is located next to transfer roller 40, on a remote side of transfer roller 40, such that the transfer roller 40 is interposed between tray 56 and backup roller 42. As can be seen in FIG. 7, tray 56 may be divided into a number of different compartments 60, each for carrying a different coating, for example paint coatings of different colors. Tray 56 has an edge surface 62 conforming to the outer surface of transfer roller 40, and is pressed thereagainst to provide a fluid-tight seal.
Roller 40 is driven in the direction of arrow 66 so that coating applied to the roller by tray 56 is carried to the upper nip 70 between rollers 40, 42. As mentioned, webbing 12 enters between rollers 40, 42 from below, passing through the lower nip 72 between the rollers. Roller 42 is driven in the same rotational sense as roller 40, as indicated by arrow 75 in FIG. 3.
As can be seen in FIG. 3, for example, webbing 12 is wrapped about a reverse or backup roller 42 and is in frictional contact therewith so as to be driven in the downstream direction of arrow 50. As can be seen in FIG. 3, at the point of contact between rollers 40, 42, the outer surfaces of the rollers are travelling in opposing directions and accordingly, a sufficient amount of rotational driving force must be applied to webbing 12 to insure a desired, steady downstream travel of the webbing. For the arrangement of the preferred embodiment, where roller 42 provides driving force for propelling webbing 12, it is desired that the webbing overlie a substantial portion of the outer surface of roller 42. As can be seen in FIG. 3, it is preferred that webbing 12 be wound about half the surface of roller 42 in order to insure an adequate frictional engagement and rotational drive of the webbing, despite the opposing force of roller 40. The present invention also contemplates driving the rollers 40, 42 in opposite rotational directions so that the tangential velocities of the rollers at the point of contact (that is, at the nip between the two) is in the same direction. Such an arrangement might be provided, for example, where a larger range of knife gap openings is not required. As will be seen herein, the unidirectional rotation of both rollers 40, 42 provides a wide range of control of final coating thicknesses on webbing 12, so as to allow a wide range of coating thicknesses and transfer rates. For example, the knife blade gap which sets the coating thickness on transfer roller 40 can be opened up or increased, with the coating applied to webbing 12 being reduced by increasing the rotational speed or diameter of the backup roller 42. The knife blade has not been shown in FIGS. 1-6, for purposes of clarity. Referring to FIG. 8, a doctor blade or knife blade 170 is located above the center line of transfer roller 40 and has a lower knife edge 172 spanning the length of roller 40, and spaced slightly thereabove with a gap dimension ranging between a fraction of 1 mil to 10 mils.
As can now be seen, it is important that movable support or adjustment be provided for each roller 40, 42, independently of one another so as to bring the rollers into alignment with webbing 12 and to provide the desired spacing and orientation of the rollers for an operation. With reference to FIGS. 1-4, and especially to the enlarged view of FIG. 41 transfer roller 40 includes a mounting shaft 80 mounted in a travelling or carriage block 82. A relatively massive frame 84 defines a hollow housing with a channel 86 within which carriage block 82 is free to reciprocate. As can be seen in FIGS. 1 and 3, for example, the frame 84 is supported by sidewall members 96, 98. A lead screw 88, threadingly engaged with members 90, 92 has a lower end 94 rotatably coupled to carriage block 82, so as to provide a vertical adjustment for the mounting shaft 80 of roller 40. Thus, the generally horizontally extending shaft 80 can be brought into desired alignment with roller 42, so as to move the nip between rollers 40, 42 to a desired angular position with respect to the center line of roller 42.
Turning again to FIGS. 1-4, and especially to FIG. 4, backup roller 42 has a central mounting shaft 100 with a keyed end 102 for mating with a gear 104. The shaft 100 is mounted in a slide or carriage block 106 (see FIG. 6). Carriage block 106 has a channel recess at its bottom portion for receiving a rail or guide block 110 which extends in the direction of webbing travel. An outer hollow frame 112 confines the guide block for moving back and forth in a generally horizontal direction, the direction of webbing travel, as indicated by double-headed arrow 116 of FIG. 4. The carriage block 106, slide block 110 and outer frame 112 comprises part of a locating means with movable support for altering the gap and/or pressure between rollers 40, 42. The locating means further includes an electromagnetic operator or solenoid 120 having a yolk shaft 122 coupled to a link rod 124. The forward, free end of link rod 124 is coupled to carriage block 106 and, as solenoid 120 is energized by electrical leads 126, the guide block 106 and shaft 100 are reciprocated, being moved toward and away from transfer roller 40.
According to one aspect of the present invention, the shafts 40, 42 each have their own independent drive systems. For example, a gear 130 is connected to a free end 132 of shaft 80 (see FIG. 2). A drive chain 134 engages gear 130 to drive roller 40 in the desired direction, at a preselected speed determined by the gear ratios. Drive chain 134 is connected to a motor-driven sprocket (not shown), but which is similar to the gear sprocket 142 (see FIG. 3). A drive chain 138 engages gear 104 to drive roller 42 with a desired direction and rotational speed. Chain 138 is coupled to a gear sprocket 142 which is driven by a motor 144. By adjusting the motor speeds and gear ratios for the drive assemblies associated with rollers 40, 42, the rollers can be operated at virtually any desired direction and rotational speed. According to one aspect of the present invention, it is preferred that motor 144 and gears 104, 142 be chosen such that roller 42 rotates at a speed which results in reducing the thickness of the coating applied to webbing 12, as compared to the thickness of the coating applied to transfer roller 40.
Referring to the schematic view of FIG. 8, a liquid coating 162 in tray 56 is picked up by roller 40 as the roller passes the tray, forming a layer 166 of coating material on the outer surface 164 of roller 40. Preferably, the rotational speed and outer surface 164 of roller 40 is chosen so that layer 166 is somewhat thicker than the desired transfer roller coating 166, located downstream of knife blade 170. The lower sharpened tip 172 of knife blade 170 limits the thickness of coating on roller 40, and insures that the coating 166 is of a desired preselected thickness. The coating 166 follows roller 40 until contact is made with roller 42, with the coating thereby being located at the upper nip 70 between the rollers. Preferably, webbing 12 carried by backup roller 42 is pressed against roller 40 so as to form a fluid-tight barrier which preserves a desired level of coating material in the area indicated by numeral 176 in FIG. 8, located at upper nip 70.
Webbing material passing through area 176 picks up coating material, thereby forming the final coating 180 on portions of webbing 12 passing downstream of the roller nip. As mentioned, rollers 40, 42 preferably rotate in the same direction so as to have tangential velocities which are oppositely directed at the point of contact between the two rollers. According to one aspect of the present invention, the relative speed between rollers 40, 42 is determined beforehand so as to achieve a final coating thickness 180 of a desired magnitude. One advantage of the present invention is that the final coating 180 can be made substantially thinner than the coating 166 on transfer roller 40. Accordingly, to achieve the same final coating thickness on webbing 12, the backup roller 42 can be operated at a relatively slower speed for a given gap 184 between the knife blade and outer surface 164 of roller 40. Alternatively, for the same thickness of final coating 180, both the gap 184 and relative speed of roller 42 can be increased.
Those skilled in the art will now appreciate an important advantage of the present invention. At times, particulate substances are found in the coating material and, when these particles or masses of particles approach the size of the knife blade gap 184 or have a size representing a substantial proportion of the gap size, defects in the final coating result, which can visibly mar the appearance of the final coating. This has been one recognized problem in conventional knife blade coating applications where the substrate to be coated passes under the knife blade, that is, where a single application roller is used.
In the present invention, particles passing under the knife blade do not directly adhere to the substrate, but rather enter the area 176 at the upper nip between the rollers 40, 42. Very substantial shear forces are present in area 176 created by the oppositely directed surface velocities of the rollers. It has been found that there is a substantial churning action in the area 176 which, for commercially practical coatings, surprisingly eliminates or greatly reduces the number of visible defects in the final coating 180. It is believed that the shear forces, churning action and turbulence in the area 176, either alone or in combination, are sufficient to break down the particle size of particles passing underneath knife blade 170.
Defects caused by particle groups, or agglomerations of colorant particles which occasionally pass under knife blade 170 have been significantly reduced. As those skilled in the art are aware, paint coatings typically include one or more colorants which frequently have a particulate component. These particulate components are very finely divided, but tend to agglomerate with the passage of time, and will be present in the coating material. With the present invention, these particulate agglomerations have been found to break up, that is, to reduce in size and number with residence in area 176 for time durations typically encountered in commercial coating operations.
The present invention provides further advantages in that the knife blade gap 184 can be increased, even while controlling the coating process so as to attain a final coating thickness substantially less than the knife gap width. For example, if the relative speed of back up roller 42 is increased, other factors being equal, the thickness of final coating 180 will decrease in relation to the speed increase. It has been found, for some types of coatings, that larger size particulate agglomerations and particles are not visually objectionable as long as they are not made to undergo substantial contact with knife blade 170, but rather, pass underneath the knife blade substantially unchanged. With the present invention, the knife blade gap can be increased so as to reduce or eliminate particle extrusion or other deformation underneath knife blade 170. As mentioned, these larger size particles may, for some coatings, tend to be reduced in size in area 176. However, for other types of coatings, particle size reduction may not be important if transfer of the final coating portion 180 can be tolerated. Such tolerance of the particles is increased for particles which have not been damaged by knife blade 170.
As can now be seen, the present invention allows the coating of special effects heretofore achieved using knife-over-roll coating methods, using superior reverse roller coating techniques so as to provide greater control over the coating process. In addition, the present invention minimizes the streaking and similar coating defects usually associated with contaminants in the coating material, which when moved into contact with the knife, visibly mar the finished coating. At times, the contaminants block the flow of coating material underneath the knife, when the contaminants are too large to pass through the gap between the knife and the roller. The contaminants need not necessarily be physically larger than the gap, but need only approach the gap dimension in order to visibly mar the finished coating. With the present invention, the gap between the knife and roller can be increased, thereby reducing these harmful effects. In addition, an agitation zone between the rollers 40, 42, has been observed to minimize visible marring of the finished coating, believed to result from the churning motion of the coating material in the agitation zone.
The drawings and the foregoing descriptions are not intended to represent the only forms of the invention in regard to the details of its construction and manner of operation. Changes in form and in the proportion of parts, as well as the substitution of equivalents, are contemplated as circumstances may suggest or render expedient; and although specific terms have been employed, they are intended in a generic and descriptive sense only and not for the purposes of limitation, the scope of the invention being delineated by the following claims. | Apparatus for coating a webbing uses rollers in contact with each other. The coating is applied to a first roller and coating thickness is limited by a knife blade. The coating travels to a point of contact with the second roller about which the webbing is wound, and the coating is thereby transferred to the webbing. By controlling the relative speed between the two rollers, the knife blade can be raised or lowered with respect to the first roller to attain greater control over the coating operation. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to rolling parts and power transmission parts formed of carbon steel produced through induction hardening.
[0003] 2. Description of the Background Art
[0004] Conventionally, rolling bearings, a typical rolling part, have often been formed for example of SUJ2 or other similar high-carbon chromium bearing steel, SCM420 or other similar, case-hardened steel carburized, or the like. They are sufficiently reliable steels for bearings. However, they are expensive as they contain Cr, Mo and other expensive elements, and using such elements also results in consumption of rare resources and thus desirably should be avoided. In particular, when SCM420 and other similar case-hardened steels are thermally processed they are required to be heated for a long period of time, or carburized, and this also consumes a large amount of thermal energy.
[0005] In contrast, in recent years automobile leg bearings and constant velocity joints (CVJ), ball screws, and any other similar rolling parts also sliding as they roll are formed of S53C or other similar medium carbon steel, with the rolling portion alone induction-hardened. Medium carbon steel has an alloy element content smaller than the afore-mentioned bearing steel and case-hardened steel and it is inexpensive and has satisfactory workability. It is disadvantageous, however, as it is inferior in important characteristics, i.e., it has a shorter rolling life.
[0006] To overcome the above disadvantage, conventionally members have been increased in size to alleviate load or surface pressure and they have thus been used without problems. In the future, however, energy conservation and miniaturization will result in high surface pressure acting on such members and a longer rolling fatigue life is thus demanded. Furthermore, CVJs, ball screws and the like can have a rolling portion also sliding as they roll, and they are thus also required to have long life accordingly. Furthermore, miniaturization requires that members be reduced in thickness and that a raw material itself corresponding to a non-hardened portion also have enhanced fatigue strength.
[0007] Furthermore as a result of the miniaturization of the part a large amount of heat is emitted and confined and the entirety of the part is thus exposed to higher temperature than conventional.
[0008] Thus, energy conservation, miniaturization and the like result in a rolling portion being used under severer conditions and a material providing a long rolling life is thus demanded. As has been described previously, CVJs, ball screws and the like can have a portion sliding as it rolls. As such they are required to have a long life not only as a simply rolling part but a rolling part which also slides. Thus the “rolling life” as aforementioned refers not only to that of a rolling part that simply rolls but that of a rolling part also sliding as it rolls
[0009] In addition to the above demand, miniaturization and associated reduction of members in thickness entail acceptance of relatively large load. As such, a raw material itself of a non-hardened portion is also required to have larger fatigue strength. In order to in crease the life of the exact raw material without increasing the cost thereof it is effective to increase the contents, as represented in percentage, of C, Si, Mn or any other similar, inexpensive alloy element in conventionally used medium carbon steel. In other words, increasing these inexpensive alloy elements in amount enhances the strength of the raw material and hence the fatigue strength the exact raw material.
[0010] If the raw material is excessively hardened, however, it would be inferior in workability. The present invention is directed to a rolling part having a complex shape, for example thread cutting. As such, turnability, forgeability, pierceability and other similar working characteristics are also important. Thus, high-carbon steel and high-alloy steel, such as bearing steel, are unsuitable. Case-hardened steel that is carburized is also unsuitable for the above rolling parts as it needs to have a treaded portion protected against carbonization and its complex shape facilitates over-carburization and if boundary oxidization occurs under mill scale the steel can be impaired in strength. To enhance workability, the raw material can have its hardness adjusted for example by a quenching and tempering process after it is cast and molded. To reduce the cost of the raw material, however, desirably the quenching and tempering process is excluded and the raw material that is not quenched or tempered is processed.
SUMMARY OF THE INVENTION
[0011] There can be obtained a rolling part and power transmission part excluding any expensive elements as its constituents and formed of inexpensive elements C, Si and Mn optimized to allow the same to have characteristics equivalent to those of rolling parts using bearing steel, and a power transmission part using the rolling part. The above characteristics are as follows: An application miniaturized and thus incapable of accepting temperature elevation, requires a rolling life allowing for its high temperature use.
[0012] (a) Rolling portion corresponding to an induction-hardened portion:
[0013] (a1) rolling life thereof as it simply rolls
[0014] (a2) rolling life thereof as it slides while rolling
[0015] (b) Non-hardened portion
[0016] (b1) limit of typical fatigue characteristics, or rotating bending fatigue
[0017] (b2) workability
[0018] The present invention in one aspect provides a rolling part formed of steel containing 0.5 to 0.8% by weight of C, 0.5 to 1.2% by weight of Si and 0.3 to 1.3% by weight of Mn and having a surface hardness of no less than HRC 59.
[0019] The steel contains 0.5 to 0.8% by weight of C to ensure that induction-hardening provides a surface hardness of no less than a predetermined value. It contains C with a lower limit of 0.5% by weight to ensure a long rolling life with a large load imposed while Si, Mn and the like are contained, as predetermined. Carbon forms carbide and to obtain steady hardness larger carbon contents, as represented in percentage, are preferable. Too high carbon contents, as represented in percentage, however, impair cold-workability, and a soaking process for prevention of component segregation, spheroidization of carbide, and other similar, particular heat treatments are required, which is costly. To ensure good cold-workability and dispense with soaking, C has an upper limit set to be 0.8% by weight.
[0020] The steel contains 0.5 to 1.2% by weight of Si because Si is an element increasing a rolling life and it also prevents the steel from softening when it is exposed to high temperature, and it acts to delay microstructural change, cracking, and the like attributable to large load applied repetitively. Medium carbon steel containing 0.5 to 1.2% by weight of C, as provided in the present invention, and containing less than 0.5% by weight of Si, cannot exhibit its effect and provides a rolling life increasing as no less than 0.5% by weight of Si increases. More than 1.2% by weight of Si, however, significantly impairs cold-workability and hot-workability and increases production cost. Si thus has an upper limit set to be 1.2% by weight. 0.3% by weight of Mn contained in the steel improves the steel in hardenability and it dissolves into solution in the steel to enhance the steel in toughness and also increases retained austenite beneficial in increasing a rolling life. Mn, however, as well as Si, reinforces a raw material and if its content as represented in percentage is too high it impairs workability and machinability. Mn thus has an upper limit set to be 1.3% by weight.
[0021] Desirably Al is low in level to ensure a long rolling life, although it is not necessarily required to be particularly low if it has approximately a normal level, and so is P.
[0022] As the above alloy components integrally act, the steel can be produced in the same process line as conventional carbon steel and provide a material providing a long rolling life. Of the above alloy elements, C, Si and Mn contribute to providing inexpensive medium carbon steel having a rolling life close to that of bearing steel and workability close to that of carbon steel. The above-described steel forming the present rolling part that is induction-hardened and tempered, can obtain hardness of no less than HRC 59. The steel for example induction-hardened ensures hardness more reliably than S53C or other similar, typical carbon steel induction-hardened, as the former contains the alloy elements C, Mn and Si increased in amount and thus has high hardenability.
[0023] In the above first aspect desirably the rolling part is formed for example of the steel containing C, Si and Mn, as represented in percentage, satisfying the following expressions (1) and (2):
L= 11271 (C wt %)+5796 (Si wt %)+2665 (Mn wt %)−6955 (1)
L≧ 5000 (2)
[0024] wherein L represents an estimated index of a rolling life obtained through multiple regression analysis. In the present invention, C, Si and Mn are limited by the condition L25000 as provided above. Thus, with hardenability and the like enhanced, hardness ensured, and the like, a further increased rolling life can be provided.
[0025] In the above first aspect desirably the rolling part is formed of the steel containing for example no more than 0.02% by weight of Al and no more than 0.02% by weight of P.
[0026] Al forms an oxide-based, non-metallic inclusion and it thus has a negative effect on a rolling life. In particular, C, Si, Mn-based steel, as used for the present rolling part, is more disadvantageously susceptible to non-metallic inclusion. No more than 0.02% by weight of Al is thus desirable.
[0027] P segregates at grain boundary and reduces toughness. As such, with austenite phase being low in state, no more than 0.02% by weight of P is desirably used to provide a long rolling life and enhanced fatigue strength.
[0028] The present rolling part is produced in a method including the steps of: processing in a predetermined shape a steel at least containing 0.5 to 0.8% by weight of C, 0.5 to 1.2% by weight of Si and 0.3 to 1.3% by weight of Mn; and induction-hardening a member processed in the step of processing. Introducing C, Si, Mn in an appropriate range more in amount than S53C or other similar, typical medium carbon steel, can maintain excellent workability and in addition ensure high hardenability. As such, the present steel can be readily processed on the same process line as conventional carbon steel and it also readily ensures a high level of hardness through induction-hardening. Furthermore, increasing Si in amount mainly can provide a high level of strength for high temperature. Thus a high yield of rolling parts can be produced efficiently.
[0029] Desirably in the present method for example the step of induction-hardening is followed by the step of tempering the member to provide a surface hardness of no less than HRC59. The steel used to form the present rolling part has a composition with Si increased in amount and thus highly resistant to softening attributable to tempering. Thus it readily ensures hardness if it is quenched and tempered at (a) relatively high temperature or (b) the same temperature for a long period of time.
[0030] The present invention in a second aspect provides a rolling part formed of steel shaped and thus processed, at least containing as alloy elements 0.5 to 0.7% by weight of C, 0.6 to 1.2% by weight of Si and 0.6 to 1.0% by weight of Mn, as represented in percentage, to satisfy the following equations (1) and (2):
L≧ 5000 (1)
[0031] wherein L represents an estimated lifetime in regression calculated from a measured value of life as the rolling part simply rolls and
L= 11271 (C wt %)+5796 (Si wt %)+2665 (Mn wt %)−6955; and 23≦H≦25 (2)
[0032] wherein H is an estimated value of the following equation:
H= 48.0 (C wt %)+5.7 (Si wt %)+11.5 (Mn wt %)−16.2
[0033] in hardness of a raw material, as calculated from a measured value of the hardness of the raw material.
[0034] In the above configuration the chemical composition has a range set for the following reason: no less than 0.5% by weight of C is required for allowing induction-hardening to ensure hardness of no less than a predetermined value and for ensuring a satisfactory rolling life with a large load imposed while Si and Mn are contained invariable in amount. Thus C has a lower limit set at 0.5% by weight. C forms carbide and to constantly ensure hardness larger amounts of C are preferred, although more than 0.7% by weight of C would result in raw material having too high levels of hardness and impair workability. Furthermore, a soaking process for prevention of component segregation, a carbide spheroidization process, and other similar, particular thermal treatments would also be required, which is costly. No more than 0.7% by weight of C is thus set.
[0035] 0.6% by weight of Si contained in the steel reinforces raw material to provide a long rolling life and also prevents it from significantly softening when it is exposed to high temperature. Furthermore the Si thus contained acts to delay microstructural change, cracking, and the like attributable to large loads applied repetitively. It also does not contribute to increasing the raw material in hardness so much as Mn described hereinafter. More than 1.2% by weight of Si impairs cold-workability and hot-workability. No more than 1.2% by weight Si is thus set.
[0036] 0.6% by weight of Mn contained in the steel improves hardenability and it dissolves into solution in the steel to enhance the steel in toughness and also increases retained austenite beneficial in increasing a rolling fatigue life. Mn, however, as well as Si, reinforces a raw material and it also dissolves into carbide and thus increases hardness thereof and hence that of the raw material. Thus more than 1.0% by weight of Mn impairs workability and machinability. Mn thus has a range set to be 0.6 to 1.0% by weight.
[0037] The above estimated value of life set to be 5,000 is required in order to provide an induction-hardened portion with a rolling fatigue life L10 of no less than 5,000 multiplied by 10 4 .
[0038] Furthermore if the raw material has an estimated value H in hardness of no less than 23 a non-hardened portion that is not quenched or tempered can have a rolling and bending fatigue strength of no less than 400 MPa. For H exceeding 25, however, it would be hardened excessively and thus impaired in workability. H of no more than 25 is thus set. These levels of hardness may be that of a material of a portion hardly varying with a low-temperature tempering process and free from an effect of induction-hardening that has been tempered in a low temperature range.
[0039] In the above, second aspect the rolling part can include a hardened portion provided by the steel shaped and thus processed that is induction-hardened.
[0040] Employing induction-hardening to provide a hardened portion can provide a rolling part with a rolling portion having a long rolling fatigue life and a long rolling and sliding fatigue life.
[0041] In the above, second aspect desirably the material of the portion free from the effect of induction-hardening has a 10 7 -time fatigue limit of no less than 400 MPa, as measured in a rotating bending fatigue.
[0042] Thus the steel can obtain a level of fatigue strength more than 30% higher on average than conventional medium carbon steel and thus endure severe conditions in use expected in the future, such as large load, large torque, and miniaturization. Note that the portion free from the effect of induction-hardening for example includes (a) raw material (before it is neither shaped nor induction-hardened), (b) a portion induction-hardened and tempered and yet free from the effect of induction-hardening, and (c) a portion induction-hardened and not yet tempered, and free from the effect of induction-hardening.
[0043] In the above, second aspect desirably the rolling part at a rolling portion corresponding to an induction-hardened portion can have a rolling life L10 of no less than 5,000 multiplied by 10 4 times, as measured in a rolling fatigue test, and a life longer than S53C, as measured in a rolling and sliding fatigue test.
[0044] As such if rolling and associative sliding stress is applied the rolling part can have sufficient durability.
[0045] A power transmission part including any one of the above rolling parts can have a satisfactory level of workability, a long rolling life and a long rolling and sliding life, and it also can have a non-hardened portion having superior fatigue characteristics. Thus it can have high durability and also be inexpensive.
[0046] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] In the drawings:
[0048] [0048]FIG. 1 represents a correlation between chemical composition and rolling life of steel used in an example of the present invention and a comparative example, as provided in first and second embodiments of the present invention;
[0049] [0049]FIG. 2 schematically shows a third generation H/U having a wheel bearing and a CVJ combined together, with a rolling part of the present invention in a second aspect applied;
[0050] [0050]FIG. 3 schematically shows a fourth generation H/U having a wheel bearing and a CVJ combined together, with the rolling part of the present invention in the second aspect applied;
[0051] [0051]FIG. 4 represents a relationship between measured and estimated values of a rolling fatigue life L10 of the present invention in a third embodiment as it simply rolls; and
[0052] [0052]FIG. 5 represents a relationship between measured and estimated values in hardness of a raw material non-quenched and non-tempered in the third embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0053] The present invention in embodiments will now be described.
EXAMPLES
First Example
[0054] The present invention in a first example provides a rolling part in a first aspect. It is formed of steel having a composition having a range determined by C, Si and Mn alone. More specifically the present invention in the first example provides steel containing 0.5 to 0.8% by weight of C, 0.5 to 1.2% by weight of Si and 0.3 to 1.3% by weight of Mn, as shown in Table 1.
TABLE 1 chemical composition (% by mass) class No. C Si Mn Cr note examples of 1 0.53 1.00 0.31 — — the present 2 0.64 0.83 0.60 — — invention 3 0.55 0.81 0.60 — — 4 0.76 0.55 1.15 — — 5 0.56 0.82 0.83 — — 6 0.60 0.80 0.60 — — 7 0.55 1.00 0.30 — — 8 0.58 1.00 0.80 — — 9 0.58 0.50 1.20 — — 10 0.61 0.88 0.72 — — comparative 1* 0.53 0.20* 0.85 — S53C examples 2* 0.63 0.10* 0.58 — — 3 0.53 0.61 0.50 — — 4* 0.55 0.11* 0.60 — — 5 0.53 0.60 0.60 — — 6* 0.53 0.38* 0.25* — — 7* 0.53 0.20* 0.25* — — 8* 0.55 0.20 0.75 — — 9* 0.45* 0.80 0.80 — — 10* 1.00* 0.25 0.35 1.50 SUJ2
[0055] As comparative example steels were prepared, as provided in Table 1. Note that although comparative examples Nos. 3 and 5 are steels containing C, Si and Mn ranged as above and thus should be included in the list of the examples of the present invention, they are included in the list of the comparative examples for the sake of the description of a second example of the present invention. The list of the comparative examples also includes S53C (No. 1), a standard steel for induction-hardening, and bearing steel SUJ2 (No. 10). Theses steels contained no more than 0.02% by weight of Al and no more than 0.02% by weight of P. All of the steels were machined and thus each shaped into a piece for a rolling life test. Then, all of the pieces of the examples of the present invention and the comparative examples of Table 1 except for comparative example No. 10, were induction-hardened to a depth of approximately 2 mm to prepare pieces for the rolling life test. Comparative example No. 10, a bearing steel, was hardened by through hardening. Additional test pieces of the examples of the present invention and those of the comparative examples were also prepared for measurement of surface hardness and it has been confirmed that Nos. 1-10 of the present invention and comparative examples Nos. 3 and 5 had a surface hardness of no less than HRC 59.
[0056] The above steels were used to prepare test piece samples and a φ12 cylinder rolling life test hereinafter referred to as a “rolling fatigue test”) was conducted on the samples. In this test a high surface pressure and a high load rate are applied to acceleratively fatigue a sample and thus estimate it. For each numbered test 15 samples were prepared and estimated in fatigue strength by L10 life, i.e., a load application frequency allowing 90% of the samples can be used without spalling. The test was conducted under the following conditions:
[0057] size of sample piece: 12 mm in diameter and 22 mm in length
[0058] size of counterpart steel ball: 19.05 mm in diameter
[0059] contact stress P max: 5.88 GPa
[0060] load rate: 46,240 times/min.
[0061] The test results are shown in Table 2:
TABLE 2 peeling test percentage rolling fatigue test of (by 10 4 ) occurrence class No. estimation measurement (%) ratio examples of 1 5640 5990 6.1 0.56 the present 2 6668 6850 6.1 0.56 invention 3 5537 5450 7.3 0.68 4 7863 7200 5.5 0.51 5 6321 6590 6.2 0.57 6 6043 6120 6.8 0.63 7 5840 5530 6.2 0.57 8 7510 7210 5.5 0.51 9 5678 5810 7.5 0.69 10 6939 7410 7.0 0.65 comparative 1** 2443** 2630 10.8 1.00 examples 2** 2271** 2005 12.8 1.19 3** 3890** 3720 9.9 0.91 4** 3079** 3300 12.1 1.12 5** 4095** 4450 8.4 0.78 6** 1887** 1920 11.9 1.10 7** 844** 900 16.5 1.52 8** 2268** 2100 17.2 1.59 9** 4885** 4610 14.9 1.38 10** 6810** 7300 7.8 0.72
[0062] Nos. 1-10 of the present invention and Nos. 3 and 5 thereof in the comparative example list all exhibit long L10 life. In particular, Nos. 4, 8 and 10, with high, appropriate C, Si and Mn contents in percentage, exhibited life almost comparable to that of bearing steel SUJ2 (comparative example No. 10).
[0063] In contrast, comparative example No. 1 (S53C) provided an L10 life of approximately 2,600 multiplied by 10 4 , No. 2, with C alone increased, provided approximately 2,000 by 10 4 , and No. 4, with Mn alone increased, provided 3,300 by 10 4 , and increasing a single element in amount is less effective. This also applies to Nos. 3 and 5 of the present invention in the comparative example list, since although C, Si and Mn fall in the range of the present invention, Si alone is increased in amount, resulting in insignificantly increased L10 lives of 3,720 by 10 4 and 4,450 by 10 4 , respectively. It is also important to ensure a satisfactory C content in percentage, and comparative example No. 9, with high Si and Mn and low C, provided a relatively small value of 4,600 by 10 4 .
[0064] [0064]FIG. 1 represents for the steels studied in the first example a relationship between C, Si and Mn contents in percentage and L10 life through multiple regression analysis. It can been seen from FIG. 1 that regression expression L of expression (1) and L10 life have an excellent correlation therebetween. Note that in FIG. 1, a repetition figure of 10 4 is represented as one.
[0065] In Table 2 a column “estimation” presents values L10 provided by the above item (1) and a column “measured result” presents test results as measured. It has been found from the test results as measured that the steels of the first example of the present invention all provide L10 longer than standard, comparative example No. 1.
Second Example
[0066] The present invention in a second example provides a rolling part of the first aspect. It is formed of steel having a composition satisfying the range of C, Si and Mn and the requirements of expressions (1) and (2). More specifically, not only the range of C, Si and Mn but also L≧5000 need to be satisfied. In the present example the rolling part and comparative examples were formed of steel, as presented in Table 1. The present example uses example Nos. 1-10 of the present invention, as listed, and comparative example steel Nos. 1-10, as listed. Each steel has a value L matching a value in the column “estimation” of a rolling fatigue test as shown in Table 2. According thereto, example steel Nos. 1-10 of the present invention all have a value L of no less than 5,000 and in contrast, comparative example steel Nos. 1-9 have a value L less than 5,000 and comparative example steel No. 10 alone has a value L no less than 5,000, although it has a C content in percentage failing to fall within the range of the present invention.
[0067] The above steels were subjected to a peeling test. In the test, a test piece in the form of a ring with a cylindrical portion having a small curvature, is attached to each of a driving shaft and a driven shaft provided parallel to the driving shaft and the test pieces have their cylindrical surfaces pressed against each other and thus rolled to see how they are damaged. The test piece were dimensioned to have a diameter of 40 mm, a width of 12 mm, and a cylindrical portion having the other principal radius of curvature of 60 mm. The test piece on the driving shaft had a cylindrical surface ground to have an R max of 3 μm in roughness and that on the driven shaft had a cylindrical surface super finished. Peeling strength is estimated by the percentage of the area of the cylindrical surface of the test piece on the driven shaft that has peeled, as observed when the test completes. The test piece on the driving shaft and that on the driven shaft were samples of a single steel, used in pair. The test was conducted under the conditions:
[0068] test piece's maximum surface roughness: 3.0 μm on the driving shaft's side and 0.2 μm on the driven shaft's side
[0069] (maximum) contact stress P max: 2.3 GPa
[0070] lubricant oil: turbine oil VG46
[0071] driving shaft's rotation rate: 2,000 rpm
[0072] total rotation rate: 4.8 by 10 5 times.
[0073] The peeling test provided a result, as also shown in Table 2. According to the result, example test pieces Nos. 1-10 peeled in an area smaller in percentage than comparative examples and exhibited satisfactory, anti-peelability equivalent to or better than comparative example No. 10 or SUJ2.
[0074] From the results of the first and second examples it can be seen that the present invention in the second example provides a rolling part having a long rolling life and superior anti-peelability and hence capable of sufficiently allowing for severer contact stress conditions, conditions facilitating peeling, and other similar conditions.
Third Example
[0075] [0075]FIGS. 2 and 3 each show a hub unit using a rolling part of the present invention in a second aspect. FIG. 2 schematically shows a third generation hub unit (H/U), a hub joint having a wheel bearing and a CVJ combined together. FIG. 3 schematically shows a further developed, fourth generation H/U. The FIG. 2 third generation H/U has one inner ring lace 2 integrated with a hub wheel 4 and the other inner ring lace 5 is crimped with hub wheel 4 . An outer ring 3 is structured to be directly fixed to a knuckle. In the third generation H/U a CVJ 1 is an independent part. In the fourth generation H/U, in contrast, it is structured to be more compact, and one inner ring lace 5 is integrated with hub wheel 4 , which is the same as the third generation, although the other inner ring lace is integrated with an outer joint ring 3 . As such the portion is required to have both of (a) a rolling fatigue life as a bearing lace portion and (b) a life as a joint for a rolling, reciprocating movement as it slides.
[0076] The third example is an example of the rolling part of the present invention in the second aspect. As shown in Table 3, the rolling part in the second aspect was formed of steels having chemical compositions A1 to A5. As comparative examples were prepared steels having chemical compositions B1 to B18 which do not fall within the range of the present invention in the second aspect. The comparative example steels, even if with C, Si and Mn in the range of the steel as provided in the second aspect, is associated with index L or H outside the range as provided in the present invention.
[0077] These steels were used as raw material to prepare (a) a piece induction-hardened to a depth of approximate 2 mm for a rolling fatigue test, (b) a piece for a rolling and sliding fatigue test, and (c) a test piece for an experiment simulating a hardness of a raw material that is not quenched or tempered. Note that as indicated in the column “note” comparative example B1 is a conventional medium carbon steel S53C and comparative example B18 is a bearing steel SUJ2.
TABLE 3 chemical composition (wt %) class No. C Si Mn Cr note examples of A1 0.56 0.82 0.83 — the present A2 0.60 0.80 0.60 — invention A3 0.53 0.62 0.98 — A4 0.63 0.62 0.60 — A5 0.52 1.16 0.74 — comparative B1 0.53 0.20* 0.85 — (S53C)L*, H* examples B2 0.53 1.00 0.31* — H* B3 0.64 0.83 0.60 — H* B4 0.55 0.81 0.60 — H* B5 0.76* 0.55* 1.15* — H* B6 0.55 1.00 0.30* — H* B7 0.58 1.00 0.80 — H* B8 0.58 0.50* 1.20* — H* B9 0.61 0.88 0.72 — H* B10 0.63 0.10* 0.58* — L*, H* B11 0.53 0.61 0.50* — L*, H* B12 0.55 0.11* 0.60 — L*, H* B13 0.53 0.60 0.60 — L*, H* B14 0.53 0.38* 0.25* — L*, H* B15 0.53 0.20* 0.25* — L*, H* B16 0.55 0.20* 0.75 — L*, H* B17 0.45* 0.80 0.80 — L*, H* B18 1.00* 0.25* 0.35* 1.5 (SUJ2)
[0078] I. Conditions for Tests
[0079] (1) Rolling Fatigue Test
[0080] The present example steels A1 to A5 induction-hardened and then tempered all achieved hardness of no less than HRC59. Thus it can be said that they can provide a level of hardness constantly higher than the conventional medium carbon steel S53C. As has been described above, conventional medium carbon steel has a disadvantage that it has a rolling life shorter than bearing steel. It is expected to be used in the future under severe conditions and desirably it should have a rolling life comparable to that of bearing steel. This rolling fatigue test was conducted to estimate a rolling life of steel as it simply rolls. The test was conducted under the following conditions. In the test a number n of 15 was set and a rolling life was estimated by L10 life.
[0081] dimension of test piece: 12 mm in outer diameter and 22 mm in length
[0082] dimension of counterpart steel ball: 19.05 mm in diameter
[0083] maximum contact stress Pmax: 5.88 GPa
[0084] load Rate: 46,240 times/min.
[0085] (2) Rolling and Sliding Fatigue Test
[0086] As well as in the rolling fatigue test, all were induction-hardened and then tempered, and provided hardness of no less than HRC 59. As has been described previously, it has been confirmed that they can provide a level of hardness constantly higher than the conventional medium carbon steel S53C. CVJs and ball screws can have their rolling portions sliding as they roll. They are thus required not only to have a long life as they simply roll but also a long life as they slide while rolling. The rolling and sliding fatigue test was a 2-cylinder test conducted to estimate a rolling life of steel as it rolls and associatively also slides. The test was conducted under the following conditions:
[0087] piece to be tested: 40 mm in outer diameter by 12 mm in width, with an outer diameter having the other principal curvature (straight)
[0088] counterpart test piece: 40 mm in outer diameter by 12 mm in width, with an outer diameter having the other principal curvature of 60 mm, and formed of bearing steel SUJ2
[0089] maximum contact stress Pmax: 3.5 GPa
[0090] rotation rate: 1,800 rpm for piece to be tested and 2,000 rpm for counterpart test piece
[0091] lubricant: turbine oil VG46
[0092] (3) Test Simulating Hardness of Raw material Non-quenched and Non-tempered
[0093] From raw material a cylinder of 30 mm in diameter by 30 mm in length was cut out and used as a test piece. Note that a “non-quenched and non-tempered” material refers to that cast and then air-cooled. If the non-quenched and non-tempered material has too high a level of hardness and in a subsequent step it is ground, bored or similarly processed with a tool in complex manners the tool could be reduced in life or the material can crack when it is worked to be bent. On the contrary, if it is too soft it cannot obtain sufficient fatigue strength and it would hardly be used under severe conditions expected in the future. More specifically, no more than HRC 25 is desirable in terms of workability.
[0094] Furthermore, increased load, increased torque and miniaturization are expected in the future and a non-hardened portion thus would receive large load. Thus desirably it has a fatigue strength greater than conventional medium carbon steel by no less than 30% on average, which is no less than 400 MPa as currently used medium carbon steel has a rotating bending fatigue limit (a 10 7 -time fatigue strength) of approximately 300 MPa on average. It is conventionally known that a rotating bending fatigue limit σwb and hardness (HV) have a relationship therebetween of σwb equal 1.54 HV. When σwb of 400 MPa is substituted in this expression, a required hardness of HRC 23 was calculated. Thus, in terms of fatigue strength, hardness of no less than HRC 23 is desirable. Accordingly, to simulate hardness of raw material non-quenched and non-tempered, a test was conducted. In the test, a test piece was held at 1,200° C. for one hour and then immediately exposed to the atmosphere and thus naturally air-cooled and the test piece then had its hardness measured at a portion in a vicinity of its center.
[0095] II. Test Result
[0096] Table 4 presents a result of each of (1) the rolling fatigue test, (2) the rolling, sliding fatigue test, and (3) the test simulating a hardness of a raw material non-quenched and non-tempered.
TABLE 4 Hardness of rolling life L 10 raw material (by 10 4 ) ratio in (HRC) meas- esti- rolling & meas- esti- ured mated sliding life ured mated class No. value value (to S53C) value value Note examples of A1 6590 6321 1.9 25.1 24.9 the present A2 6120 6043 1.5 24.7 24.1 invention A3 5361 5224 1.7 24.6 24.0 A4 5588 5338 1.4 24.9 24.5 A5 7789 7601 1.8 23.8 23.9 comparative B1 2630 2443* 1.0 20.2 20.2* S53C examples B2 5990 5641 0.6 19.4 18.5* B3 6850 6668 1.2 28.0 26.2* B4 5450 5538 1.6 22.2 21.7* B5 7200 7864 1.0 35.5 36.6* B6 5530 5840 0.6 21.0 19.4* B7 7210 7510 1.5 27.0 26.5* B8 5810 5678 1.6 27.3 28.3* B9 7410 6940 1.4 25.6 26.4* B10 2005 2271* 0.7 21.7 21.3* B11 3720 3887* 1.3 19.6 18.5* B12 3300 3079* 0.9 17.1 17.7* B13 4450 4095* 1.6 19.6 19.6* B14 1920 1887* 0.3 13.6 14.3* B15 900 844* 0.5 12.9 13.3* B16 2100 2402* 0.9 19.3 20.0* B17 4610 4886* 0.5 18.3 19.2* B18 7300 6698 1.4 35.7 37.3* SUJ2
[0097] The standard S53C (comparative example B1) measured approximately 2,600 by 10 4 and bearing steel SUJ2 (comparative example B18) measured approximately 7,300 by 10 4 in L10 (a 10% longevity) as they simply roll, and S53C was no more than half in L10 of SUJ2. The steel of the present invention, configured of inexpensive chemical components alone, could not be comparable to bearing steel SUJ2, although desirably it has an L10 of no less than 5,000 by 10 4 , a value approximately at least twice that of S53C. It can be seen that example A1-A5 of the present invention are all have an L10 having a satisfactory value no less than 5,000 by 10 4 .
[0098] In addition, they have an average life no less than 1.5 times greater than S53C and superior to SUJ2 as they slide while rolling. Furthermore, the example steels of the present invention all have their respective raw materials simulating to be non-quenched and tempered having hardness within a range of 23≦HRC≦25, as measured. In contrast, comparative example steels B2-B9 exhibit L10s of no less than 5,000 by 10 4 and comparative examples B4, B7 and B8 in particular also have their rolling and sliding lives no less than 1.5 times greater than S53C. These comparative example steels, however, all have their raw materials each having a harness failing to fall within 23<HRC≦25, as measured. Note that in spite of their rolling lives rather longer than S53C, comparative examples B2 and B6 each have a rolling and sliding life shorter than S53C. A chemical composition with more Si and less Mn tends to provide a shorter rolling and sliding life.
[0099] Lifetime, as measured, and hardness of raw material, as measured, as the steel simply rolls, went through multiple regression analysis to obtain a correlation thereof with chemical components C, Si and Mn. The multiple regression analysis provided a multiple regression expression, as represented in expressions (1) and (2) for estimation. With reference to Table 4, an estimated lifetime L and an estimated hardness H of raw material as the steel simply rolls, are values obtained by substituting the steel's chemical composition into expressions (A) and (13):
L =11271 (C wt %)+5796 (Si wt %)+2665 (Mn wt %)−6955 (A)
H =48.0 (C wt %)+5.7 (Si wt %)+11.5 (Mn wt %)−16.2 (B),
[0100] wherein “%” represents “% by weight.”
[0101] [0101]FIG. 4 represents fatigue life of steel as it simply rolls and FIG. 5 represents hardness of raw material, as represented in an expression for estimation and measured. It can be seen from the figures that the measured and estimated values have an excellent correlation therebetween. More specifically, it means that if the amounts of chemical components C, Si and Mn contained are found, as represented in percentage, fatigue life as the steel simply rolls and hardness of raw material can both be estimated with high precision.
[0102] In the present example, in addition to the steel's individual chemical components, estimated values L and H obtained from expressions (A) and (B) need to satisfy the following conditions:
L≧5,000 (1)
23≦H≦25 (2).
[0103] Together with the range of each of chemical components C, Si and Mn, estimated values L and H determined these chemical components that satisfy expressions (1) and (2) allow the present rolling part to have all required characteristic.
[0104] Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation. For example the present invention has a scope including:
[0105] (a) a rolling part which may be a shaped and thus processed product that is not induction-hardened, as most generally defined; and
[0106] (b) a shaped and thus processed product induction-hardened and thereafter entirely tempered.
[0107] The spirit and scope of the present invention is limited only by the terms of the appended claims and further includes any variation equivalent in meaning and range to the claims as recited. | There can be obtained a rolling part and power transmission part excluding any expensive elements as its constituents and formed of inexpensive elements C, Si and Mn optimized to allow the same to have a long rolling life under severe conditions for use and be inexpensive and excellent in workability. It is formed of steel shaped and thus processed, and containing 0.5 to 0.7% by weight of C, 0.6 to 1.2% by weight of Si and 0.6 to 1.0% by weight of Mn, as represented in percentage, to satisfy:
L≧5000 (1),
wherein L=11271 (C wt %)+5796 (Si wt %)+2665 (Mn wt %)−6955; and
23≦H≦25 (2),
wherein H=48.0 (C wt %)+5.7 (Si wt %)+11.5 (Mn wt %)−16.2. | 8 |
The United States Government may have rights in this application pursuant to Contracts NIHR01CA57530 and P30CA4457906F1.
This application is a regular National application claiming priority from Provisional Application, U.S. application Ser. No. 60/014,375 filed Mar. 28, 1996.
BACKGROUND OF THE INVENTION
Field of the Invention
This invention pertains to antibodies specific for Gamma-Glutamyl Transpeptidase (GGT), inactive prodrugs useful in the treatment of GGT-expressing tumors, and methods of administration of the same. Specifically, a peptide-specific antibody is provided which provides for assays for the detection of GGT expression in solid tumors. Such tumors can be targeted and treated by administration of novel prodrugs which are activated by GGT on the surface of the tumor to be treated. The inactive prodrug is non-toxic, permitting simultaneous elevation of local dosage, with reduced side-effects.
Background of the Prior Art
It is widely acknowledged that many chemotherapeutic regimens fail because the side-effects of the drugs used limit the dose that can be administered. This is particularly true of solid tumors. The clinically tolerated doses are often insufficient to kill all of the cells, thereby enriching the tumor population for drug resistant mutants. Among the surviving tumor cells in below-effective treatment regimens are mutant cells that arise spontaneously within the tumor cell population, and are resistant to the treatment drug. Each subsequent round of chemotherapy enriches the population for the resistant cells, which grow and continue to mutate, some to even higher levels of resistance. There is an established linear-log relationship between dose and tumor kill. The higher the dose of the drug, the greater the chance of eradicating the tumor. While methods have been developed to selectively target and kill tumor cells, many of the targeting methods either reduce the effectiveness of the drug, call for a complex series of reactions to prepare a drug, etc.
In the consideration of solid tumors, it should be recognized that local effective dosage, and systemic dosage, need not be the same. Thus, the only effective portion of the chemotherapeutic agent administered is that which reaches the tumor cell. Many chemotherapeutic agents are administered systemically, however, and only a limited portion of the dosage administered actually reaches the cell. Thus, dose limitations frequently result in only a fraction of the permitted dosage actually reaching the cell. The term local dosage is used herein to describe that dosage which actually reaches the targeted tumor cell population.
It is has been recognized that many human tumors express high levels of GGT. Hanigan et al., Cancer Res. 54:286-290 (1994) and Dempo et al., Oncodevelop. Biol. Medicine 2:21-37 (1981). GGT is a cell surface glycoprotein that cleaves glutathione, glutathione-conjugates and other gamma-glutamyl compounds. Hanigan et al., Carcinogenesis 6:165-172 (1985) and Lieberman et al., Am. J. Pathol. 147:1175-1185 (1995). The function of GGT is most clearly defined in the kidney. GGT is present on the luminal surface of the proximal tubule cells where it cleaves glutathione and glutathione-conjugates in the glomerular filtrate. Curthoys et al., Enzyme 24:383-403 (1979). Glutathione cannot be taken up intact by most cells. GGT cleaves the gamma-glutamyl bond of glutathione releasing glutamic acid and cysteinyl-glycine (CG). CG that can then be hydrolyzed by dipeptidases and the three amino acids reabsorbed. Hanigan et al., Biochemistry 32:6302-6306 (1993). This is the first step in the conversion of such compounds to mercapturic acids.
Studies have demonstrated that induction of GGT is one of the earliest markers of preneoplastic liver cells. Goldsworthy et al., CRC Critical Reviews in Toxicology 17:61-89 (1986). GGT can provide a selective growth advantage to tumor cells by cleaving serum glutathione and thereby providing cells with a secondary source of cysteine. Hanigan et al., Carcinogenesis, supra. It has been postulated that GGT may be critical to the effectiveness of chemotherapeutic agents by effecting the intracellular glutathione levels and by initiating the further metabolism of glutathione-conjugated drugs. Ahmad et al., J. Cell Physiology 131:240-246 (1987) and Hanigan et al., Cancer Research 54:5925-5929 (1994).
Accurate assessments of the presence and amount of GGT expression in human tissues has been difficult however. One assay of choice employs antibodies, which are conventionally used in immunoblotting assays such as Western Blot Technology, and the like. Because the tissue of particular focus is solid tumor tissue, the antibody should preferably be susceptible of use in immunohistochemical staining assays.
The provision of an antibody that detects GGT is not straight forward. The antibody must meet several criteria. The antibody must detect GGT in formalin-fixed sections of human tissues. The antibody must be directed against the peptide backbone of the protein because post-translational modification of GGT, such as glycosylation and addition of sialic acid differs between normal and neoplastic tissue. Yamaguchi et al., Pancreas 4:406-417 (1989) and Arai et al., Clin. Chim. Acta. 210:35-36 (1992). Further, the antibody should not detect the inactive form of GGT encoded by the alternately spliced form of human GGT MRNA that has been detected in the liver, kidney, brain, intestine, stomach, placenta and mammary gland tissues. Pawlack et al., J. Biol. Chem. 265:3256-3262 (1990).
The difficulties encountered in detecting GGT in neoplasmas have also been hampered by a lack of comprehensive analysis of distribution of GGT in normal human tissues. Many human tissues have never been analyzed for GOT expression. There are conflicting results regarding the localization and level of GGT expression in many tissues. Goldbarg et al., Arch. Biochem. Biophys. 91:61-70 (1960), Glenner et al., J. Histochem. Cytochem. 10:481-489 (1962), Albert et al., Acta. Histochem. 18:78-89 (1964) and Shiozawa et al., J. Histochem. Cytochem. 37:1053-1061 (1989).
Accordingly, it remains an object of those of skill in the art to be able to determine the presence of GGT expression in human tumor cells, and, if detected, to advantageously employ the expression of GGT in effecting high local doses of chemotherapeutic agents without toxicity or severe side effects.
The dose limiting side effects of a wide variety of chemotherapeutic agents have been well documented. Among the most promising chemotherapeutic agents, and those in use, are doxorubicin, bleomycin, hydroxyurea, 9-aminocamptothecin and amonafide. Doxorubicin side-effects include cardiomyopathy and myelosuppression as well as nausea and vomiting. Chabner et al., Clinical Pharmacology of Cancer Chemotherapy, in Cancer: Principles and Practice of Oncology, 156-197 (Lippincott 1982). Treatment with bleomycin induces subacute or chronic pneumonitis that progresses to interstitial fibrosis which can be fatal, Id. Hydroxyurea is toxic to the bone marrow. Id. 9-aminocamptothecin can cause neutropenia, nausea and vomiting. Dahut et al., J. Clin. Oncol. 14:1236-1244 (1996). Amonafide, currently in clinical trials, has been reported to cause mylosuppression, vomiting and venous irritation at the infusion sight. Levitt et al., J. Neuro-Onc. 23:87-93 (1995) and Marshall et al., Am. J. Clin. Oncol. 17:514-515 (1994). These side effects limit the systemic dosage that may be administered. The local dosage experienced by the tumor cells is a small fragment of the limited systemic dosage, giving rise to the repeated cycle of survival and resistance described above.
Accordingly, it remains an object of those of ordinary skill in the art to find a way to provide higher local dosages of these side effect dose-limited chemotherapeutic agents, and other agents similarly dosage-limited.
SUMMARY OF THE INVENTION
The above objects, and other objects elaborated more fully below, are met, in part, by the provision of a peptide-specific antibody, GGT 129, that meets the aforementioned criteria for GGT expression detection. The antibody is directed against a peptide of the c-terminus of the heavy subunit of GGT. The 20 amino-acid peptide has the sequence CDTTHPISYYKPEFYTPDDGG (SEQ. ID. NO:1), employing the conventional 1-letter code for amino acids. The peptide, when conjugated to KLH by incubating 0.5 mg peptide and 1.0 mg KLH in 100 mm sodium phosphate buffer, pH 7.4, with 0.2% glutaraldehyde for four hours at room temperature is obtained when the incubation mixture is dialyzed against PBS. Antibodies to the KLH-conjugated peptide can be obtained through conventional measures, e.g., immunizing host organisms, such as rabbits or mice, with the conjugated peptide, recovering the serum therefrom, and isolating the antibody.
The antibody is specific for the peptide. This is the first known antibody specific for a peptide within human GGT. As noted above, GGT is subject to abundant glycosylation and sialic acid residues that are variable. If an antibody is raised against purified GGT, lack of staining may be due to failure to bind due to random variations, rather than the absence of GGT. Additionally, the inactive form expressed by many tissues may be bound by an antibody prepared against the purified GGT, since the inactive form (a truncated form) contains most of the heavy subunits. The identified peptide is not found in the inactive or truncated form, avoiding false positives.
Detection of positive expression of GGT in tumor tissues of potential patients permits treatment of the tumors with altered chemotherapeutic agents. Specifically, agents, such as those discussed above and others, are modified to be inactive as administered. The agents are modified by binding a gamma-glutamyl group at a site rendering the drug inactive. The inactive prodrug travels through the bloodstream in the inactive form, which is non-toxic, until it encounters GGT-positive tumor cells. The GGT expressed on the surface of the cells cleaves the gamma-glutamyl inactivating group, releasing the active form of the drug, achieving a high local dosage, while avoiding dose-limiting side effects. Although many normal tissues express GGT it is localized to the luminal surface of ducts and tubules where it would not be able to activate prodrugs in the serum or in the intestitial fluid. Chemotherapeutic agents should be selected to avoid requirements of activation by the liver, or other tissues distant from the tumor, and should not have significant kidney toxicity, since, as noted above, GGT is expressed in the kidneys.
As GGT has been confirmed to be expressed on the surface of the cells of a wide variety of tumors, and many chemotherapeutic agents are susceptible to inactivation by gamma-glutamyl attachment, to provide a form non-toxic to the patient, the invention makes many tumors amenable to new chemotherapeutic strategies not hampered by low dose limits to avoid side effects.
DESCRIPTION OF THE FIGURES
This invention may be further understood by reference to the figures submitted herewith, summarized in the descriptions set forth below.
FIG. 1 schematically illustrates the reactions catalyzed by GGT. The Group R designates any chemical group. The acceptor can be any number of amino acids, peptides or water.
FIGS. 2A-2C provide structural representation of 3GGT substrates. Substrates 2A, 2B and 2C are, respectively, glutathione, gamma-glutamyl-p-nitroanilide and leukotriene C 4 . GGT cleaves the substrates at the gamma-glutamyl bound, designated by an arrow. The only specificity of the structural diverse compounds that serve as substrates for GGT is the gamma-glutamyl-amide linkage.
FIG. 3 is a schematic illustration of the synthesis of gamma-glutamyl amonafide.
FIG. 4 provides structural illustrations of chemotherapeutic drugs and their corresponding gamma-glutamyl prodrug derivatives of the claimed invention.
FIG. 5 is a schematic representation of the synthesis of gamma-glutamyl hydroxyurea.
FIGS. 6A and 6B are a graphic illustration of the results of in vitro toxicity testing of a amonafide and gamma-glutamyl amonafided on GGT-positive and GGT-negative PC3 cells. GGT-positive results are designated by open circles and GGT-negative results are designated by closed circles.
DETAILED DESCRIPTION OF THE INVENTION
This invention includes the peptide-specific antibody for detection of GGT expression in tumor cells and other tissues, assays employing that antibody, GGT-inactivated chemotherapeutic agents, their activation by GGT on the surface of target cells, and methods of administration of these agents to treat specific tumor conditions. While each aspect is described, below, discretely, and may be used separately, the invention provides a complete regimen for the assessment of general tumor types, assay of specific individuals for tumor GGT expression, and treatment of the same. Accordingly, although separate provisions are described separately, below, each is considered part of a greater whole.
GGT-SPECIFIC ANTIBODY
The antibody of the invention, designated GGT129, is prepared against a 20 amino-acid sequence specific to the c-terminus of the heavy subunit of human GGT. The peptide sequence is CDTTHPISYYKPEFYTPDDGG (SEQ. ID. NO:1). This peptide was synthesized with an N-terminal cysteine using conventional technology. The synthesized peptide was conjugated with keyhole limpet hemocyanin (KLH) using conventional technology. Antibodies to the KLH-conjugated peptide were prepared in New Zealand white rabbits, using conventional technology.
The antibody was obtained through affinity purification. Peptide-specific antibody was purified from the serum of the immunized animals by affinity column chromatography. The peptide was linked, via the sulfhydryl group on cysteine to Sulfolink® gel from (Pierce, Rockford, Ill.). A second affinity column was prepared with the peptide and Affi-Gel 15 (Bio-Rad, Richmond, Calif.). After application of the serum obtained from the hosts, columns were rinsed with PBS containing 0.5M NaCl. High-affinity antibody was eluted from both columns by lowering the pH to 2.8. Affinity-purified antibody was dialyzed vs. PBS and stored at -80° C. in 1% BSA. Both columns yielded purified antibody effective for immunohistochemical staining.
Samples of normal human myometrium, intestinal epithelium and endometrium were obtained from surgical specimens, Department of Pathology, University of Virginia Health Sciences Center. Human liver and kidney were obtained from autopsy material. Tissue was stored at -80° C. Tissue was homogenized with a Potter-Elvehjem homogenizer in PBS at 4° C. The protein concentration in the homogenate was determined by BCA protein assay (Pierce).
Washed human sperm were obtained from the Human Gametes and Embryo Laboratory, University of Virginia Health Sciences Center. Sperm were washed free of seminal fluid by pelleting through a two-step Percoll gradient (47.5 and 90% Percoll) then washed with Biggers Whitten and Whittingham medium (Irvine Scientific, Irvine, Calif.) containing 5 mg/ml human serum albumin.
GGT activity in the tissue homogenates and washed human sperm was quantified according to the method of Tateishi et al., Gann. 67:215-222 (1976). Glycylglycine 40 mM was used as an acceptor. One unit of GGT activity is defined as the amount of enzyme that releases 1 μmol p-nitroaniline per minute at 25° C. Tissue homogenates were diluted to 0.5 mg/ml in 125 mM Tris, pH 6.8, 1% SDS, 5% β-mercaptoethanol, 10% glycerol and were boiled for 2 minutes. Samples (1 μgram per lane) were electrophoresed on 5-20% polyacrylamide-SDS gel and electroblotted to nitrocellulose (0.45 μpore) (Schleicher and Schuell, Keene, N.H.). The blots were blocked overnight at 4° C. in 10 mM Tris, pH 8.0, 150 mM NaCl, 0.05% Tween 20 (TBST) containing 5% bovine serum albumin. Blots were rinsed in TBST, and incubated for 2 hours at room temperature in affinity-purified GGT129 diluted 1:20,000 relative to the serum concentration. Blots were washed in three changes of TBST and incubated for 2 hours with peroxidase-conjugated goat anti-rabbit IgG diluted 1:10,000 in TBST. After a fmal rinse in TBST, immunolabeled bands were visualized by enhanced chemiluminescence (BM cherniluminescence wester blotting reagents) (Boehringer Mannheim, Indianapolis, Ind.).
5 μm sections from routine zinc formalin-fixed, paraffin-embedded normal tissues were obtained from archival autopsy and surgical pathology blocks at the University of Virginia Health Sciences Center. For immunohistochemical staining, paraffin was removed and the tissue rehydrated with four 10-minute incubations in xylene, three 5-minute incubations in 100% ethanol, three 5-minute incubations in 95% ethanol and a 5-minute wash in distilled water. Endogenous peroxidase activity was inhibited by two 15-minute incubations in 0.3% H 2 O 2 in methanol, followed by two 5-minute washes in PBS. Endogenous biotin was blocked with a 15-minute incubation in avidin blocking solution (Avidin/Biotin block kit) (Vector Laboratories, Burlingane, Calif.). A 3-minute wash in PBS, a 15-minute incubation in biotin blocking solution and a 10-minute wash in PBS. Slides were incubated for 10 minutes in PBS containing 1.5% normal goat serum (Gibco) (Grand Island, N.Y.). Affinity-purified GGT129 antibody in 1% BSA was diluted in 1.5% goat serum-PBS. The primary antibody was diluted 1:1,000 relative to the starting serum concentration. Slides were incubated for 45 minutes in primary antibody. Control sides were incubated in an equivalently diluted solution of 1% bovine serum albumin. The antibody was removed and slides were washed for 3 minutes in PBS. The slides were incubated with biotinylated anti-rabbit IgG and avidin-linked peroxidase (Vectastain Elite ABC peroxidase kit) (Vector). Peroxidase was localized with the Biogenex liquid DAB substrate (Biogenex, San Ramon, Calif.). Slides were incubated for 3 minutes in 0.5% cupric sulfate to fix the stain, rinsed in deionized water and counterstained for 3 minutes in Gills Hematoxylin. All incubations were done at room temperature. After rinsing, the slides were dehydrated with 95% and 100% ethanol and xylene, then cover slipped with Permount. A section of normal human kidney was included as a positive control with each section stained.
Sperm were assayed for GGT activity by the biochemical assay described above. In addition, washed sperm were smeared on a glass slide, air-dried and stained histochemically for GGT activity as previously described in Hanigan et al., (1994) supra.
Western blot analysis of whole tissue homogenates was used to determine the specificity of the GGT129 antibody. GGT was analyzed in human myometrium, intestinal epithelium, endometrium, liver, and kidney. Biochemical assay of GGT activity in the homogenates showed that myometrium had less than 1 U GGT activity/g protein, intestinal epithelium, 3.6±0.4 U/g protein, endometrium 7.0±0.3 U/g protein, liver 20.7±0.9 U/g protein, and kidney 103±2.0 U/g protein. The homogenates were subjected to SDS-PAGE electrophoresis, blotted, and stained with the GGT129 antibody. A single band at approximately 66 KD, corresponding to the heavy subunit of human GGT, was reactive with the antibody. Among the tissues analyzed, the relative level of GGT activity corresponded to the amount of the heavy subunit detected on the Wester blot.
Immunohistochemical staining with the anti-GGT polyclonal antibody revealed that GGT was restricted to specific cell types (Table 1). The majority of GGT-positive cells were epithelial. In addition, macrophages in many tissues were immunoreactive. Fat and muscle were consistently GGT-negative. Fibrous stroma was generally negative for GGT, but thin bands of immunopositive fibroblasts were seen in some sections of bladder, colon, liver, breast, and ovary.
Concordant with the high levels of GGT activity measured by the biochemical assay, immunohistochemical staining revealed intense positivity of renal proximal tubule cells with localization to the luminal surface. The glomeruli and distal tubules were negative. The transitional epithelium of the bladder and the ureter was negative for GGT. As noted above, in some sections the stroma under the transitional epithelium was positive for GGT.
Major and minor salivary gland epithelium showed strong immunohistochemical staining, with localization to the apical surface of salivary ducts. The acini were negative. Bronchial and lung epithelium lacked GGT staining. Alveolar macrophages were weakly GGT-positive. Esophageal squamous epithelium was negative, but duct cells draining the submucosal glands were positive. Analysis of the stomach showed no staining of the surface epithelium, but weak apical staining was observed in some of the antral mucous glands. The duodenum and small intestine had weak positive apical staining of the crypts and very weak positive staining on the intestinal surface. Crypts and epithelium in the colon and appendix were negative. Goblet cells lacked immunoreactivity. Macrophages within the appendix were positive.
In the liver, GGT was localized to the bile canaliculi of the hepatocytes. The staining was most intense in the hepatocytes near the portal areas. The luminal surface of biliary epithelium in both the small and the large ducts was also positive. The apical surface of the gallbladder epithelium was moderately stained. In the pancreas, the acinar cells were strongly positive and apical staining of the duct epithelium was present. Islet cells were completely negative.
In the brain and spinal cord, the endothelial cells lining the capillaries showed striking GGT-positivity. The endothelial cells lining arteries were negative, although weak staining was present in the perivascular cells surrounding large arteries. Neurons and glial cells were negative.
Many cells within the male reproductive system showed high levels of GGT immunostaining. In the testis, the Sertoli cells had strong apical membrane immunoreactivity and Leydig cells were moderately positive. An undescended testicle devoid of germ cells was stained for GGT to highlight the Sertoli cells, which stained strongly positive. The epithelium lining the epididymis, seminal vesicle, and vas deferens showed high levels of GGT on the apical surface. The luminal surface of the glandular epithelium in the prostate was GGT-positive, although the underlying basal epithelial cells were negative. GGT was present in seminal fluid, making it difficult to ascertain whether germ cells were GGT-positive. Therefore, human sperm washed free of seminal fluid were stained histochemically and assayed biochemically for GGT activity. Sperm were negative for GGT activity with both methods.
TABLE I______________________________________Immunobissochemical detection of GGT in normalhuman tissuesTissue Immunopositive cells______________________________________Urinary systemKidney Proximal tubule cellsBladder Stroma under transitional epithelium (focal)Respiratory systemBronchus Salivary ductsLung Alveolar macrophages (weak)Digestive tractSalivary gland Salivary ductsStomach Antral mucous glands (focal, weak)Duodenum and Crypts and lining epithelium (very weak)ileumColon Stromal cells (focal)Appendix MacrophagesLiver Bile ducts and canaliculiGallbladder Surface of epitheliumPancreas Acinar cells and ductsReproductive systemTestis Sertoli cells and Leydig cellsEpididymis Epithelium and secretionsSeminal vesicle EpitheliumVas EpitheliumProstate Epithelium and secretionsOvary Leydig cells (weak) Stromal cells (focal, weak)Fallopian tubes Nonciliated epithelium (moderate to weak) and cilia on ciliated epitheliumEndometrium Secretory and proliferative phase epithelium and secretionsCervix Endocervical glands and secretionsBreast Ducts and ductulesImmune SystemSpleen Connective tissue around arteriolesLymph nodes MacrophagesEndrocine GlandsAdrenal Capillary endothelium cortical cells (weak)Parathyroid Capillary endotheliumThryroid Follicular epithelium (weak)Nervous systemBrain and spinal cord Capillary endotheliumOtherSkin Sweat glands (eccrine)Placenta Amnion and chorionUmbilical cord Amnionic cellsFetusKidney Proximal tubulesIntestine EpitheliumLiver Bile canaliculiPancreas DuctsAdrenal cortex Cortical epithelium______________________________________
The female reproductive tract had less intense GGT-positivity than the male system. Germ cells, surface epithelium, and most stromal cells in the ovary were negative. Leydig cells showed a very weak level of staining. Occasionally, a small group of spindle-shaped stromal cells within the ovary was GGT-positive. The cilia on the epithelium of the Fallopian tubes stained positive, and nonciliated epithelium was weakly stained. Within the uterus there was amixture of GGT-positive and -negative glands in both the secretory and the proliferative phase of the menstrual cycle. The fluid within the GGT-positive secretory glands was also GGT-positive. Uterine smooth muscle was negative. The squamous epithelium of the cervix was negative, whereas the endocervical glands and their luminal secretions had moderate staining intensity at the surface. Breast tissue showed variable apical staining of the epithelium of the ducts and ductules. Secretions within the positive ductules were also GGT-positive.
Squamous and sebaceous epithelia of the skin, skeletal muscle, cardiac muscle, fat, nerves, and blood vessels were all GGT-negative. Sweat glands (eccrine) showed apical immunostaining. In the spleen, some of the connective tissue around arterioles and within the stroma showed GGT-positive staining. Splenic lymphocytes and those within lymph nodes were negative. However, tingible body macrophages and other histiocytes within lymph nodes were immunoreactive.
In the adrenal gland, the capillary endothelial cells were positive for GGT. The adrenal cortical cells were very weakly immunopositive, unlike the adrenal medullary cells, which were negative. Follicular epithelial cells in the thyroid showed GGT staining, whereas the colloid did not show GGT activity. Staining of parathyrod epithelium was negative.
Placental and fetal tissues were also analyzed for GGT immunoreactivity. Trophoblasts and chorionic villi were negative, whereas cells in the chorionic layer and amnion were moderately GGT-positive. Expression of GGT in fetal tissue was similar to that in adult tissue. In a 12-week-old fetus, the tissue that expressed GGT included proximal tubules in the kidney, bile canaliculi of the hepatocytes, ducts within the pancreas, and the apical surface of the intestinal epithelium. The adrenal cortex was weakly positive. Tissues that did not express GGT included hematopoietic elements within the liver, skeletal muscle, and cartilage. Gestational endometrium was also positive.
Following the above methods, irnmunostaining of a variety of human tumors, for expression of GGT, has been conducted. The results of GGT expression testing of human tumors is summarized in Table II.
TABLE II______________________________________Expression of GGT in Human Tumors # GGT-Positive TumorsHistologic Classification Total # of Tumors Analyzed______________________________________CarcinomasBreast 61/83Prostate 70/71Ovarian (Epithelial) 16/22Adrenal 0/3Hepatocellular 11/12Renal 6/7Intestinal 6/10Pancreaticobiliary 10/11Endometrial 7/12Basal Cell 0/9Squamous Cell 3/13Urethral 2/3Extramammary Paget's 3/6Salivary 3/10Gastric 3/9Thyroid 21/22Lung 22/24Embryonal 2/2OtherPleural Mesotheliomas 0/10Lymphomas 0/21Sarcomas 7/55______________________________________
The results of the GGT testing set forth above contain important implications for determining GGT-mediated chemotherapy, as discussed below. GGT is expressed on the brush border of the renal proximal tubule cells. Any drug that is excreted in the urine that would be activated by GGT would be present in the kidneys. Accordingly, drugs having pronounced renal toxicity are not promising candidates for the GGT-mediated chemotherapy discussed below.
GGT is also expressed on the luminal surface of epithelium lining glandular tissues. This includes sweat glands, salivary glands, hepatic bile canaliculi, pancreatic acini, mammary duct, prostate glands and endocervical glands. GGT is restricted to the luminal surface of these cells. Due to the localization of the enzyme in these tissues, it is unlikely that GGT would be in contact with prodrugs transported by the blood. Prodrugs taken up by the glandular cells and excreted into the lumen might be activated to the active form by GGT. Accordingly, chemotherapeutic agents that would be toxic to these epithelia would not make preferred candidates.
GGT is also expressed by the endothelial cells lining the brain capillaries. GGT prodrugs transported in the blood are not activated by GGT in the brain, however. Misicka et al., Life Sciences 58:905-911 (1996). GGT activation appears to occur only when the prodrug would be injected intrathecally.
GGT is also expressed at low levels on some peripheral blood mononuclear cells. The blasts, which are killed by many chemotherapeutic drugs, are GGT-negative. The GGT level of activity on peripheral blood mononuclear cells is sufficiently low as to be unlikely to activate a prodrug inactivated by gamma-glutamyl linkage.
GGT is also elevated in the serum of patients with impaired liver function, due to pathological conditions such as cirrhosis, gallstones and the like. The use of GGT-mediated prodrugs in patients with elevated serum levels of GGT would not provide for enhanced local dosages.
Additional detailed discussion of human tissue GGT expression, as reflected in Tables I and II, and the assays set forth above, can be found in Hannigan et al., J. Histochem. Cytochem. 44:1101-1108 (1996) which is not prior art with respect to this application, and is incorporated herein by reference. To the extent specific tissues strongly express GGT on their surface, or would otherwise uptake GGT-mediated prodrugs, selection of chemotherapeutic agent so as to be nontoxic to critical tissues is important.
The immunolocalization studies summarized in Table II demonstrate that there is heterogeneity among tumors with regard to GGT expression. Prostate tumors were most consistently GGT-positive, and high percentages of both breast and epithelial ovarian tumors were also GGT-positive. This heterogeneity indicates that in each patient to be treated, the tumor to be treated will have to be stained for GGT expression in order to determine which patients would benefit from treatment with the GGT-mediated prodrugs discussed below. It should be noted that many of the tumors with consistent GGT expression are poorly differentiated. The neoplastic cells do not form glandular structures. The lack of polarization in the tumor cells results in GGT being distributed over the entire cell surface. As a result, the GGT on these tumor cells would be in contact with the prodrugs coming into the cell from the blood. Cleavage of the prodrug would provide a high local concentration of the active parent compound desired. Poorly differentiated tumors often present at a high stage and generally do not respond well to standard doses, in particular side effect-limited doses, of chemotherapeutic drugs. These tumors are likely to be the ones to most benefit from GGT-mediated prodrugs discussed below.
GGT-MEDIATED PRODRUGS
To increase local dosage without inducing side effects, conventional agents will be modified by derivatizing these chemotherapeutic compounds with proven activity against solid tumors. This strategy is applicable to a wide range of structurally diverse compounds. Five compounds are representative: 9-aminocamptothecin, a topoisomerase I inhibitor; bleomycin, which produces DNA strand breaks; hydroxyurea, an inhibitor of ribonucleotide synthesis; amonafide, a topoisomerase II inhibitor; and doxorubicin, an anthracycline with antitumor activity. None of these compounds requires activation by the liver and none have significant kidney toxicity. Each can be derivatized to a gamma-glutamyl prodrug that may be inactive as a toxin. This invention should not be understood to be limited to these agents.
GGT is a cell surface enzyme. A general formula for the reaction catalyzed by GGT is shown in FIG. 1. It cleaves gamma-glutamyl amide bonds, and can transfer the gamma-glutamyl group to a primary amine on free amino acids or peptide acceptors. The enzyme can also use water as an acceptor resulting in the hydrolysis of the substrate. Glutathione and glutathione conjugated compounds are the most common physiologic substrates for the enzyme. However, as shown in FIG. 2, GGT can utilize a wide variety of gamma-glutamyl compounds as substrates. GGT can cleave gamma-glutamyl derivatives of a diverse group of drugs. The only specificity in the structure of the substrate is that it contain a free glutamic acid linked via the carboxy-terminus of the side chain to an amine group. GGT does not transport substrates or products across the cell membrane. Gamma-glutamyl prodrugs of this invention are designed to be inactive until GGT cleaves the gamma-glutamyl group thereby liberating the active parent compound.
Synthesis of Gamma-Glutamyl Amonafide
Amonafide is a topoisomerase II inhibitor that is currently in phase II clinical trials. Amonafide gamma-glutamyl prodrug has been synthesized. It serves as a prototype to demonstrate the principle that addition of a gamma-glutamyl group can stabilize a drug in an inactive form and the gamma-glutamyl derivative can be activated by GGT-positive cells.
The protocol for synthesis of the drug is as follows: N, N-Dimethylethylenediamine (8.22 mmol) was added dropwise to a suspension of 3-nitro-1,8-naphthalic anhydride (4.11 mmol) in ethanol (20 ml). The dark solution was refluxed for 4 hr. The solvent was evaporated off and the crude product, mitonafide, was purified by column chromatography eluting with methanol in chloroform (1:9). SnCl 2 .H 2 O (3.51 mmol) and H 2 O (0.125 μl) were added to a solution of mitonafide (0.702 mmol) in ethanol (5 ml). The solution was refluxed until the reaction was completed (1,5 h) as analyzed by analytical thin-layer chromatography (TLC). TLC was carried out on precoated aluminum backed silica gel 60F-254 plates (Merck) and were visualized with phosphomolybdic acid/ethanol solution. The solution was cooled to room temperature and poured onto ice. The pH was neutralized to pH 7-8 with NaHCO 3 powder, and the aqueous layer was extracted with ethyl acetate (3×10 ml). The organic layers were combined, dried over Na 2 SO 4 and filtered. The solvent was removed under reduced pressure yielding the product as a bright yellow solid (100%) and was used without further purification. 1 H NMR spectra of the amonafide were obtained with a General Electric QE300 spectrometer at 300 MHz. All chemical shifts are recorded in ppm. Elemental analyses were performed in The Department of Chemistry on a Perkin-Elmer PE 2400 C,H,N analyzer. 1H NMR (300 MHz, CDCl 3 ) δ 8.22 (d, J=7.5 Hz, 1H), 7.90 (s, 1H), 7.83 (d, J=8.4 Hz, 1H), 7.50 (t, J=8.1 Hz, 1H), 4.23 (t, J=6.6 Hz, 2H), 4.08 (bs, 2H), 2.60 (t, J=6.6 Hz, 2H), 2.30 (s, 6H).
A solution containing (0.265 mmol) of amonafide derivative 3 (FIG. 3) and (0.53 mmol) N-Carbobenzyloxy-D-glutamic acid-α-benzyl ester in CH 2 Cl 2 (2 ml) was cooled to 0° C. Dicyclohexylcarbodiimide (0.53 mmol) and a catalytic amount Dimethylaminopyridine (10 mol%) was added and the solution was stirred overnight. The urea was filtered off, the filtrate was concentrated under reduced pressure and purified by column chromatography eluting with methanol in chloroform (1:9) to yield N-Carbobenzyloxy-α-Benzyl ester-D-Glutamyl-γ-amonafide (74%). 1 H NMR (300 MHz), CDCl 3 ) δ 9.0 (bs, 1H), 8.74 (bs, 1H), 8.40 (d, J=7.2 Hz, 1H), 8.21 (s, 1H), 8.01 (d, J=8.4 Hz, 1H) 7.64 (t, J=7.2 Hz, 1H), 7.34 (bm, 10H), 5.83 (d, J=7.2 Hz, 1H), 5.19 (d, J=3 Hz, 2H), 5.15 (s, 2H), 4.55 (m, 1H), 4.33 (t, J=6 Hz, 2H), 2.75, (m, 2H), 2.52 (m, 2H), 2.41 (s, 6H), 2.38 (m, 2H).
The protected glutamyl-amonafide 3 (0.188 mmol) was dissolved in ethanol (5 ml) and a catalytic amount of 10% Pd/C was added. The solution was stirred under H 2 (1 atmosphere) for 48 h. The suspension was filtered through a Celite plug and the solvent was evaporated off under reduced pressure. The product, gamma-glutamyl-amonafide, was recrystallized in methanol/acetone and isolated as yellow brown crystals (90%). 1 H NMR (300 MHz, CD 3 OD) δ 8.62 (s, 1H), 8.55 (s, 1H), 8.37 (d, J=7.5 Hz, 1H), 8.17 (s, J=7.5 Hz, 1H), 7.67 (t, J=7.2 Hz, 1H), 4.40 (t, J=6 Hz, 2H), 3.78 (m, 1H), 3.41 (t, J=5.4 Hz, 2H), 3.15 (s, 6H), 2.63 (m, 2H), 2.14 (m, 2H).8
The synthetic approach for the other agents follows the methodology developed for gamma-glutamyl amonafide. The desired amine-containing drug is coupled with α-benzyl N-carbobenzoxy-glutamate to generate the bis-benzyl protected gamma-linked glutamyl prodrug through carbodiimide-mediated ester activation protocols. The protected prodrug may then be deprotected via hydrogenolysis to yield the free gamma-glutamyl prodrug. With the exception of hydroxyurea, each of the parent drugs is known to be stable to these chemical transformations.
Synthesis of Gamma-Glutamyl 9-Aminocamptothecin:
9-Aminocamptothecin is a DNA toposiomerase I inhibitor currently undergoing clinical evaluation. The drug exhibits low aqueous solubility and its activity can be profoundly attenuated by the binding to human serum albumin of the ring-opened hydroxy carboxylate, which is produced by hydrolysis of the lactone and appears to be in equilibrium with the parent. The basis for this observation appears to be that the selective binding (>200:1) of the carboxylate to albumin shifts the equilibrium toward the acid. Thus, development of a water soluble prodrug with low serum albumin binding affinity capable of localized release may have significant implications for the chemotherapy of GGT expressing tumors. In particular, epithelial ovarian carcinoma appears to be responsive to DNA topoisomerase I inhibitors. Gamma-glutamyl 9-aminocamptothecin may enable significant dose escalation in the treatment of this disease, since upon GGT-mediated release of the parent drug from the inactive prodrug, the parent drug should be locally absorbed or systemically inactivated by association with serum albumin.
The chemistry of camptothecin has been extensively investigated with a full range of synthetic manipulations undertaken. The chemistry for the development of gamma-glutamyl 9-aminocamptothecin is well precedented.
Synthesis of Gamma-Glutamyl Bleomycin:
The bleomycins are a family of glycopeptide antibiotics that exhibit potent cytotoxic activities. The activity of the bleomycins is thought to be a consequence of DNA damage mediated through oxygen free radical species produced by the iron-complexed antibiotic. Although complex, the molecule has been synthesized and extensive synthetic manipulation of the bleomycin framework has been conducted. The bleomycin structures vary primarily in the terminal, intercalation segment of the molecule, as illustrated by the A 2 and B 2 structures illustrated in FIG. 4. For the bleomycin systems that do not possess guanidine side chains (e.g., bleomycin A 2 ), acylation can occur at multiple sites with the primary amino groups of the β-aminoalanyl and the 4-aminopyrazone moieties exhibiting the greatest nucleophilicities. Regiochemically selective amino acylation can occur through modulation of the conditions and the presence of metal ions. Thus, either amino or both primary amine groups may undergo gamma-glutamylation with slight modification of the reaction conditions for the aminoacylation protocol.
Synthesis of Gamma-Glutamyl Doxorubicin
Doxorubicin is a DNA topoisomerase II-directed agent, that additionally exhibits redox activity. The drug has undergone extensive structure-activity studies in efforts to optimize the therapeutic index. These studies have included the development of a range of N-acyl derivatives which are currently under clinical evaluation. The N-acyl derivatives exhibit intrinisically lower DNA topoisomerase I inhibitory activity. Moreover, since anthracycline intercalation appears to be the initial step in the formation of the drug-DNA-enzyme complex, the incorporation of the amino acid side chain into the anthracycline framework would be anticipated to additionally depress intercalation and hence topoisomerase II-mediated activity. The synthetic entries into the N-acylated doxorubicin species are analogous to the methodology above; hydrogenolysis of benzyl-protecting groups appended to the anthracycline skeleton has been previously undertaken. Thus, precedent for the synthesis of gamma-glutamyl doxorubicin is available.
Synthetic Approach to Gamma-Glutamyl Hydroxyurea
Gamma-glutamyl hydroxyurea cannot be synthesized by the route outlined above, becasue the hydroxyl moiety of hydroxyurea is more reactive in acylation reactions and because the molecule is sensitive to reduction under the hydrogenolysis procedure. A number of N'-acyl hydroxyurea derivatives are known and one, caracemide (N-acetyl-N-(methylcarbamoyloxy)-N'-methylurea; NSC 253272), has undergone clinical evaluation as an antitumor agent. The target for this agent appears to be similar to that of hydroxyurea, although the mechanism of enzyme inactivation may be distinct and occur through transacylation processes. However, caracemide, a triacylamine derivative, exhibits lability in aqueous solutions hydrolyzing to the diacylamine derivative, which may be a substrate for subsequent deacylation. Thus, caracemide may be a prodrug, either hydrolyzing directly or enzymatically releasing the species acive in the inhibition of ribonucleotide reductase.
The synthetic route outlined for the preparation of gamma-glutamyl hydroxyurea is illustrated in FIG. 5. The synthesis proceeds by aminoacylation of tertiary-butyl N-BOC-glutaminate with carbonyl diimidazole, followed by treatment with hydroxylamine.
ANTITUMOR ACTIVITY
The prodrugs of this invention may be tested for activity against tumors assayed positively for GGT expression by both in vitro and in vivo testing. Actual testing, and testing protocols, are set forth below. These are not exclusive, and other testing protocols known to those of skill in the art may be employed.
Initially gamma-glutamyl prodrugs are tested in vitro for toxicity toward GGT-positive and GGT-negative tumors. Performing these experiments in a controlled manner requires cell lines that differ only in their expression of GGT. three human tumor cell lines will be used: PC3 cells, a human prostate tumor cell line, SK-OV-3 a human ovarian tumor cell line and MDA-MB-231, a human breast cancer cell line. These three cell lines which do not express GGT may be transfected with a plasmid containing cDNA for human GGT. The prodrug is tested for toxicity in both the GGT-positive and GGT-negative cells from each line. Data on the toxicity of gamma-glutamyl amonafide in GGT-positive and GGT-negative PC3 cells is presented below. These in vitro tests also provide information on the solublity and stability of the gamma-glutamyl prodrugs.
Gamma-glutamyl prodrugs may also be tested for activity against tumors formed in nude mice from the GGT-positive and GGT-negative cell lines. With the in vitro and in vivo testing gamma-glutamyl prodrugs that are as efective as the parent compound in killing GGT-positive tumors, but are not toxic to GGT-negative cells as determined by their inability to kill GGT-negative tumors may be identified.
GGT-Positive and GGT-Negative Human Tumor Cell Lines
Three human tumor cell lines have been chosen for these studies: the PC3 cell line, a human prostate cell line established from a bone metastasis of a prostatic adenocarcinoma, SK-OV-3 a human ovarian tumor cell line and MDA-MD-231 a human breast cancer cell line. We obtained the PC3 cell line (ATCC CRL 1434) from the American Type Culture Collection (Rockville, Md.). PC3 cells were tested for expression of GGT by both biochemical and histochemical assays and found to be GGT-negative. The SK-OV-3 cell line (ATCC HBT 77) and MDA-MD-231 cell line (ATCC HTB 26) may be obtained from ATCC as well. Both of these cell lines are reported to be GGT-negative.
GGT-positive PC3 cell lines and GGT-negative control cell lines were constructed with GGT/pLEN-PT, an expression vector containing a full length cDNA clone for GGT. This same transfection vector was used to transfect NIH/3T3 cells and Hepa 1-6 cells. We use the same vector and transfection strategy to obtain GGT-positive SK-OV-3 cells and MDA-MD-231 cells. Briefly, the transfection is done using the calcium phosphate transfection kit from Stratagene (LaJolla, Calif.). Five×10 5 cells are transfected with 10 μg of pLEN/GGT plus 2 μg of pWLneo, a transfection vector that contains a G418 resistance marker. Control cells are transfected with pWLneo alone. Stable transformants are selected by the addition of G418 to the culture medium. Independent colonies of G418 cells are picked and grown into cell lines. Cell lines are characterized histochemically and biochemically for GGT expression.
Toxicity Testing in vitro
The gamma-glutamyl prodrug and the parent drug are tested for toxicity toward GGT-positive and GGT-negative cells. The cells are plated in 96-well dishes, allowed to attach and grow for several days. Test compounds are dissolved in culture medium. The test protocols include experiments in which the cells are exposed to the drugs continuously for 3 days and experiments in which the cells are exposed to the drugs for 3 hours then the drugs removed and fresh medium added back to the cells. Three days after the beginning of the drug exposure the number of viable cells is determined by the MTT assay. Briefly, the MTT assay is a calorimetric assay in which the tetrazolium salt, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) is converted to the colored product formazan by dehydrogenase activity in living cells. The assay provides a quantitative measure of the number of viable cells per well and can be read on a multiwell scanning spectrophotometer. Each 96-well plate can be used to test 24 solutions, each in triplicate plus a blank well without cells to determine background absorbence. With the MTT assay multiple dilutions of the parent drug and gamma-glutamyl prodrug can be rapidly assayed for toxicity. The in vitro experiments include dose response curves and analysis of the time course of toxicity. Cultures containing mixtures of GGT-positive and GGT-negative cells are used to test the toxicity of the prodrugs and parent compounds. Since GGT is on the surface of the cell it cleaves the prodrug extracellularly. While applicants do not wish to be bound by this theory once the drug is activated it enters and kills adjacent GGT-negative tumor cells as well as the GGT-positive tumor cells. This is important, because many GGT-positive clinical tumors contain a mixture of GGT-positive and GGT-negative cells. In order to destroy the entire tumor the activated prodrugs would have to kill the GGT-negative cells surrounding the GGT-positive tumor cells.
GGT-Positive and GGT-Negative Tumors in Nude Mice
PC3 cells form tumors when injected into nude mice. There is an extensive literature on the development of PC3 tumors in nude mice because PC3 tumors have been used to test the therapeutic activity of experimental chemotherapy drugs. Both SK-OV-3 and MDA-MD-231 cells also form tumors in nude mice and can be used to test the therapeutic effect of chemotherapy drugs in vivo.
Athymic nu/nu mice may be obtained from Takonic Farm (New York, N.Y.). Athymic nu/nu mice are housed in isolation boxes supplied with Hepa-filtered, forced air and acidified water. Cages, bedding and food are autoclaved prior to use. All surgical procedures including injection of tumor cells are performed in a sterile laminar flow hood (BSL2 cabinet, Class II type A/BE).
For experiments with the PC3 cells, 10 6 GGT-positive PC3 cells or 10 6 GGT-negative PC3 cells are dispersed in a 1:1 dilution of matrigel (Collaborative Research Inc.) at 4° C. and injected subcutaneously into 6-week old athymic nu/nu mice. This protocol results in the formation of visible tumors at 100% of the injection sites in 2 to 3 weeks. Seventy-two animals are injected, 36 with GGT-positive PC3 cells and 36 with GGT-negative PC3 cells. After measurable tumors have arisen, 12 of the animals in each group may be treated with the parent compound, 12 with the gamma-glutamyl prodrug and 12 serve as untreated controls. The parent compound and the gamma-glutamyl prodrug are administered at equimolar doses. The doses are derived from previously published in vivo studies of the parent compound in mouse tumor model systems. The drugs should be injected interperitoneally . Intravenous injections in mice are technically difficult and generally inconsistent. None of the surfaces lining the peritoneum are GGT-positive so the gamma-glutamyl prodrugs should be absorbed into the blood stream intact. Tumor size is measured weekly with slide calipers. Tumor growth is monitored following treatment. Animals are weighed weekly. Throughout the experiment animals are observed daily. If animals become moribund, cachectic or unable to obtain food or water they are euthanized. The length of the experiment is dependent on the rate of growth of the tumors and the response of the tumors to treatment. Based on related studies with cisplatin the experiments may conclude 2 to 3 months after the beginning of treatment. At the conclusion of the experiment tumors are excised, weighed and processed for immunochemical and histologic analysis.
Histochemical and Histologic Analysis of Tumors from Nude Mice
At the time the animals are sacrificed the tumors are removed and fixed in Bouin's fixative. To ensure that the tumors retain their GGT-positive and GGT-negative phenotype one-third of the tumors in each group of animals is immunostained with the rabbit polyclonal antibody GGT129. (Note that the cells were transfected with the cDNA for human GGT). The fixed tissue is embedded in paraffin, sectioned at 4 μm. The tumors are immunostained. The immunostaining procedure will be the same one used to stain the clinical tumors.
In vitro Toxicity of Amonafide and Gamma-Glutamyl Amonafide toward GGT-Positive and GGT-Negative PC3 Cells
Amonafide and the prodrug derivative gamma-glutamyl amonafide were tested for toxicity towards GGT-positive and GGT-negative prostate tumor cells. The results demonstrate that the parent compound was equally toxic to both GGT-positive and GGT-negative cells. Addition of the gamma-glutamyl group inactivated the drug so that it was no longer toxic to GGT-negative cells. Gamma-glutamyl amonafide was activated by and was toxic to the GGT-positive cells.
GGT-Positive and GGT-Negative PC3 Cells
The PC3 cell line (ATCC CRL 1434) is a human prostate tumor cell line established from a bone metastasis of a prostatic adenocarcinoma. PC3 cells obtained from ATCC were tested for expression of GGT with biochemical and histochemical assays and fond to be GGT-negative. The GGT-positive PC3 cells and control PC3 cells transfected with the selectable antibiotic resistance marker were maintained in RPMI 1640 media (BRL/GIIBCO Laboratories, Grand Island, N.Y.), with 10% fetal bovine serum (HyClone Laboratories, Logan, Utah) and penicillin-streptomycin (BRL/GIBCO Laboratories, Grand Island, N.Y.).
Toxicity Assay
The toxicity of the amonafide and gamma-glutamyl amonafide towards GGT-positive and GGT-negative PC3 cells was assessed with the MTT assay. GGT-negative and GGT positive cells were plated in 96-well dishes. The cells attached and grew for several days. Test compounds were dissolved in RPMI-1640 medium. Cells were exposed to the drugs for 3 hours, after which the drugs were removed and replaced with RPMI 1640 medium containing 10% fetal bovine serum and penicillin-streptomycin. Three days after the drug exposure the number of viable cells was determined by the MTT assay.
Results of Toxicity Assays
The results of our experiments with amonafide and gamma-glutamyl amonafide show that a three hour exposure to the parent compound, amonafide, was equally toxic to both the GGT-positive and GGT-negative PC3 cells. However, the gamma-glutamyl derivative was 10-fold more toxic to the GGT-positive cells than the GGT-negative cells. These data clearly demonstrate that GGT-positive cells can activate the prodrug. FIG. 6. It is unclear why very high concentrations of the gamma-glutamyl prodrug was toxic to the GGT-negative cells. One possible explanation is that a low level of parent drug was present as a contaminant in the preparation of the gamma-glutamyl amonafide.
The above invention, including the GGT129 antibody, five specific prodrugs, methods of administration and the like have been described in terms of generic expressions, and by specific example and embodiment. Examples and embodiments set forth are not limiting, except where so indicated. In particular, other chemotherapeutic agents, selected according to the guidelines set forth above, will occur to those of ordinary skill in the art for inactivation by gamma-glutamyl attachment, and may be effectively used in this invention. Dosages will vary, from patient to patient, and prodrug to prodrug. The in vitro and in vivo testing programs set forth above will allow those of ordinary skill in the art to empirically establish acceptable dosage levels. As dosage levels for the parent compounds of the prodrugs disclosed and claimed herein have already been established in the art, these are a starting point from which higher levels that may be tolerated can be calculated. Further, the antibody described has been obtained through methods specifically set forth and disclosed. Other antibodies, having identical or similar binding affinity and specificity for GGT can be obtained through identical or similar methods. The preparation of these similar antibodies does not involve inventive skill, and such antibodies remain within the scope of the invention. In particular, derivatives of the peptide for which the antibody is specific, as well as other conjugation agents to generate an immunogenic response will occur to those of skill in the art, without the exercise of inventive faculty. The invention is not so limited, unless expressly restricted by the claims set forth below.
__________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 1(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 21 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:CysAspThrThrHisProIleSerTyrTyrLysProGluPheTyrThr151015ProAspAspGlyGly20__________________________________________________________________________ | An antibody is provided which binds to active GGT, and can identify tissues which express GGT on their surface. Many solid tumors express GGT on their surface. Individuals identified with such tumors may be treated with inactivated prodrugs of chemotherapeutic agents at local dosage levels substantially above the maximum dosage levels currently permitted due to side effect limitations. The prodrugs are comprised of chemotherapeutic agents rendered inactive by the attachment of a gamma-glutamyl group thereto. The gamma-glutamyl group is cleaved by GGT on the surface of solid tumor cells expressing GGT, and thus active only locally against the tumor. Side effects are suppressed. The antibody is used to identify solid tumors that are candidates for this treatment, as well as to identify tissues which express GGT and which must therefore be the basis of selection criteria of various available chemotherapeutic agents. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an magnetic brake and more particularly to an improved electromechanical braking device especially useful for motor vehicles.
2. Description of the Prior Art
One such magnetic brake is known from U.S. Pat. No. 5,185,542. The known magnetic brake has one rotatable part and one rotationally fixed part, which are in frictional or positive engagement with one another in a braking position of the magnetic brake, so that the rotatable part is held or at least braked by the rotationally fixed part, and which in a released position of the magnetic brake are free of one another, so that the rotatable part is freely rotatable. For actuation, the known magnetic brake has a spring element, which presses the rotationally fixed part or the rotatable part against the respectively other part, as well as an electromagnet, which by being supplied with current disconnects the rotatable part and the rotationally fixed part from one another counter to the force of a spring element; that is, the spring element puts the magnetic brake in its braking position and keeps it there, and the magnetic brake can be released by means of the electromagnet. It is equally possible to put a magnetic brake into the braking position by supplying current to the electromagnet, while conversely a spring element releases the magnetic brake.
The magnetic brake has the disadvantage that in the event of a defect, or in other words if its electromagnet or its power supply fails, it cannot be actuated.
ADVANTAGES OF THE INVENTION
The magnetic brake of the invention as defined by the characteristics of claim 1 has a second electromagnet, with which it is actuatable. The magnetic brake of this invention is advantageous because it has a magnetic brake that is actuatable selectively by its first or second electromagnet; the two electromagnets are redundant. This has the advantage of high operational reliability of the magnetic brake of the invention; failure is virtually precluded.
Preferably, the two electromagnets are each connected to their own, mutually independent power supplies, so that there is also redundance in terms of the power supply for actuating the magnetic brake, which further reduces the likelihood of failure of the magnetic brake (claim 2).
In a preferred feature of the electromechanical wheel braking device, the magnetic brake is embodied in bistable form (claim 3); that is, it remains both in the released position and in the braking position without current being supplied to its electromagnets. The electromagnets serve to switch the magnetic brake over from the released position to the braking position and conversely from the braking position into the released position. For the switchover between the two positions, only a brief supply of current selectively to the first or the second electromagnet is necessary. The bistable embodiment of the magnetic brake can be done for instance with the aid of a permanent magnet, which keeps the magnetic brake in one of its two positions counter to the force of a spring element, while conversely, after the switchover by means of one of its two electromagnets, the magnetic brake is kept in the other position counter to the force of the permanent magnet by the spring element; the force of the permanent magnet in this other position of the magnetic brake is weakened by an air gap, caused by the switchover, in its magnetic circuit.
In a feature of the invention in accordance with claim 4 , the magnetic brake is part of an electromechanical braking device for a motor vehicle; it serves to lock the electromechanical braking device in the actuated position, so that a braking force generated with the braking device is kept constant, without current being supplied to the electromechanical braking device. Supplying current to the electromechanical braking device is necessary solely to generate or boost the braking force and/or to reduce the braking force, which is understood also to mean a complete release of the electromechanical braking device. The electromechanical braking device can as a result be used as a parking brake, which once a braking force has been brought to bear maintains it without current being supplied. The electromechanical braking device can also be locked during a braking event with constant braking force using the magnetic brake, so that the braking force is maintained without current being supplied to the braking device. Only in order to vary the braking force is the magnetic brake switched into its released position and is current supplied to the braking device in such a way that its braking force varies in the desired way. In a preferred feature, the electromechanical braking device is embodied in non-self-locking fashion; that is, it releases itself when there is no current to the electric motor and the magnetic brake is released, because of a reaction force to the contact pressure force with which its friction brake linings are pressed against a brake body, such a brake disk or a brake drum, except for a negligible residual braking force. This feature of the invention has the advantage that the electromechanical braking device can be released in every case, because of the redundance of the magnetic brake, even if its electric motor or its power supply fails. It is therefore unnecessary to provide a second electric motor to release the electromechanical braking device in the event of a defect. The expense for enabling the release of the electromechanical braking device even in the event of a defect is minimal; it is limited to the provision of a second electromagnet for the magnetic brake.
DRAWING
FIG. 1, an axial section through a magnetic brake of the invention; and
FIG. 2, an axial section through an electromechanical braking device according to the invention.
The two drawing figures, for the sake of clarity, are schematic illustrations of exemplary embodiments of the invention and are to different scales.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The magnetic brake 10 of the invention, shown in FIG. 1, has a cup-shaped housing 12 of ferromagnetic material. An annular permanent magnet 16 with axial magnetization is mounted concentrically in the housing 12 , on a bottom 14 of the housing 12 . In a continuation of the permanent magnet 16 , a hollow-cylindrical magnet core 18 of ferromagnetic material is mounted concentrically with the housing 12 on the permanent magnet 16 . Two annular magnet coils 20 , 22 are slipped onto the magnet core 18 , axially adjacent one another. The magnet coils 20 , 22 are located in an annular interstice between the magnet core 18 and the housing 12 . Each magnet coil 20 , 22 , together with the magnet core 18 , forms one electromagnet 18 , 20 ; 18 , 22 . A helical compression spring 26 is inserted as a spring element into a cylindrical interior 24 inside the hollow-cylindrical magnet core 18 and inside the annular permanent magnet 16 ; this spring is braced against the bottom 14 of the housing 12 and presses against an armature disk 28 , which is disposed on a side, remote from the bottom 14 , of the permanent magnet 16 and of the two electromagnets 18 , 20 ; 18 , 22 in the housing 12 of the magnetic brake 10 . The armature disk 28 is joined to the housing 12 in an axially displaceable fashion but fixed against relative rotation by means of preferably a plurality of splines 30 , which are distributed over the circumference of the housing 12 and extend longitudinally of the housing and are integral with the housing 12 , and which protrude inward in the housing 12 and engage complimentary grooves 32 in the circumference edge of the armature disk 28 . Only one pair of splines 30 and grooves 32 can be seen in the drawing.
On an end face of the armature disk 28 remote from the permanent magnet 16 and the two electromagnets 18 , 20 ; 18 , 22 , a brake lining 34 in the form of an annular disk is fixedly mounted. A coupling disk 36 is disposed on the side of the brake lining 34 in the housing 12 , on its open face end remote from the bottom 14 . The coupling disk 36 is press-fitted for instance onto a shaft 38 , coaxial with the housing 12 , of an electric motor not shown in FIG. 1 and in this way is disposed rotatably in the housing 12 of the electromagnet 10 .
The function of the magnetic brake 10 of the invention is as follows: The magnetic brake 10 has two stable positions, namely the braking position, shown in FIG. 1, and a release position, not shown, in which the armature disk 28 rests on an end face, toward it, of the two electromagnets 18 , 20 ; 18 , 22 . In other words, the magnetic brake 10 is embodied in bistable form. In the braking position shown, the helical compression spring 26 presses the armature disk 28 , which is axially movable in the interstice between the coupling disk 36 and the two electromagnets 18 , 20 ; 18 , 22 , with its brake lining 34 against the coupling disk 36 . The armature and coupling disks 28 , 36 are joined together in a manner fixed against relative rotation by the contact pressure force of the helical compression spring 26 because of frictional engagement; that is, the armature disk 28 which is fixed against relative rotation in the housing 12 keeps the coupling disk 36 in a manner fixed against relative rotation in the housing 12 . Since in the braking position, there is an axial air gap, between the magnet core 18 and the armature disk 28 , that weakens a magnet field exerted by the permanent magnet 16 onto the armature disk 28 via the magnet core 18 , the force of the helical compression spring 26 is greater than the magnetic force exerted on the armature disk 28 by the permanent magnet 16 ; that is, the helical compression spring 26 presses the armature disk 28 against the coupling disk 36 , counter to the magnetic force of the permanent magnet 16 .
For switching the magnetic brake 10 over to the released position, one of the two magnet coils 20 , 22 is supplied with current in such a way that it increases the magnetic field of the permanent magnet 16 , specifically so markedly that the magnetic force is greater than the force of the helical compression spring 26 , so that the armature disk 28 is attracted to the magnet core 18 counter to the force of the helical compression spring 24 . As a result, the brake lining 34 is lifted from the coupling disk 36 , and the coupling disk 36 is freely rotatable. After the switchover to the released position, the current through the magnet coil 20 , 22 is turned off again. Since in the released position of the magnetic brake 10 the armature disk 28 rests directly on the face end of the magnet core 18 , so that there is no longer any air gap, the magnetic force exerted by the permanent magnet 16 via the magnet core 18 suffices to keep the armature disk 28 in contact with the magnet core 18 , counter to the force of the helical compression spring 26 . Accordingly, when it is without current, the magnetic brake 10 remains in its released position. The magnetic circuit is closed by the magnet core 18 via the armature disk 28 , contacting in the released position of the magnetic brake 10 , and via the housing 12 .
To switch the magnetic brake 10 back into the braking position, one of the two magnet coils 20 , 22 is supplied with current, now in the opposite direction, so that the magnet field generated by the magnet coil 20 , 22 that is supplied with current is in the opposite direction from the magnetic field of the permanent magnet 16 . In this way, the magnetic field is weakened, specifically so much that the helical compression spring 26 forces the armature disk 28 away from the permanent magnet 16 and the two electromagnets 18 , 20 ; 18 , 22 and presses it with its brake lining 34 against the coupling disk 36 , and as a result the magnetic brake 10 is again in the braking position. The magnetic brake 10 can accordingly be switched over from the braking position into the released position by a brief current pulse through one of its two magnet coils 20 , 22 , and can be switched back from the released position to the braking position by a current pulse of opposite polarity. When it is without current, the magnetic brake 10 stays either in the braking position or in the released position.
The two magnet coils 20 , 22 are connected to mutually independent power supplies, not shown in the drawing. If one of its two electromagnets 18 , 20 ; 18 , 22 or one of the two mutually independent power supplies for the electromagnets 18 , 20 ; 18 , 22 fails, the magnetic brake 10 can accordingly still always be switched over; as a consequence, it has high operational reliability.
The housing 12 , on its open face end, has a screw flange 40 , which is integral with the housing 12 and has screw holes 42 , and with which the magnetic brake 10 can be flanged, for instance to an electric motor, not shown in FIG. 1, or other device, with a shaft 38 that is meant to be locked intermittently.
FIG. 2 shows an electromechanical wheel braking device 44 according to the invention, which is embodied as a disk brake and which can be locked with the magnetic brake 10 shown in FIG. 1 and described above. The wheel braking device 44 has a floating caliper 46 , in which a pair of friction brake linings 48 are mounted on both sides of a brake disk 50 that can be set into rotation between them.
For pressing one of the two brake linings 48 against the brake disk 50 , the wheel braking device 44 of the invention has a spindle drive 52 , which is built into its floating caliper 46 . For the sake of low friction and high efficiency, the spindle drive 52 is embodied as a rolling-contact thread drive in the form of a roller thread drive. It has a threaded spindle 56 , resting coaxially in a spindle nut 54 , and eight profile rollers 58 , which are disposed in an interstice between the spindle nut 54 and the threaded spindle 56 . The profile rollers 58 have profiling extending around the circumference, which has a form that is complimentary to a profile of a nut thread 60 of the spindle nut 54 and to a threaded profile 62 of the threaded spindle 56 that matches the threaded profile of the nut thread 60 . The profiling around the circumference of the profile rollers 58 has no pitch. In a departure from the exemplary embodiment shown, however, it is also possible (not shown) to embody the profile rollers 58 with profiling with a pitch, or in other words with a thread. With their profiling, the profile rollers 58 engage both the nut thread 60 and the spindle thread 62 . Driving the spindle nut 54 to rotate drives the profile rollers 58 to execute an orbiting motion about the threaded spindle 56 , like planet wheels of a planetary gear. During their orbiting motion, the profile rollers 58 roll along the spindle thread 62 ; during the orbiting motion about the threaded spindle 56 , they execute a rotational motion about their own axis. By way of the orbiting profile rollers 58 , a rotational drive of the spindle nut 54 brings about a translational motion of the threaded spindle 56 in the axial direction.
The spindle drive 52 is embodied in non-self-locking fashion; that is, a thread pitch of the spindle thread 62 and of the nut thread 60 is selected to be so great that a force, acting in the axial direction on the threaded spindle 56 , sets the spindle nut 54 to rotation and displaces the threaded spindle 56 axially.
The spindle nut 54 is supported rotatably in the floating caliper 46 by a pair of axial angular roller bearings 70 and is braced axially on the floating caliper 46 via the angular roller bearings 70 .
For rotationally driving the spindle nut 54 , the wheel braking device 44 of the invention has an electric motor 64 , which is flanged to the floating caliper 46 at a right angle to the spindle drive 52 . The electric motor 64 drives the spindle nut 64 via a bevel gear system 66 , 68 , which has a plate gear wheel 66 , press-fitted onto the spindle nut 54 in a manner fixed against relative rotation, meshing with which is a bevel gear wheel 68 that is press-fitted onto a shaft 38 of the electric motor 64 in a manner fixed against relative rotation. The electric motor 64 is embodied as an electronically commutatable motor.
The threaded spindle 56 is integral with a brake lining plate 72 , which is embodied on a face end of the threaded spindle 56 toward the brake disk 50 . The brake lining plate 72 has a groove, not visible in the drawing, which is engaged by a spline 74 that is integral with the floating caliper 46 . In this way, the threaded spindle 56 is held in the floating caliper 46 in a manner secure against relative rotation. One of the two friction brake linings 48 is mounted fixedly on the brake lining plate 72 of the threaded spindle 56 . The other friction lining 48 rests in the floating caliper 46 in a manner known per se.
The magnetic brake 10 is mounted on the electric motor 64 on a face end remote from the spindle drive 52 . It is screwed to the electric motor 64 by means of screws 76 that are inserted through its screw flange 40 . The shaft 38 of the electric motor 64 protrudes from the electric motor 64 on both sides. On a side of the electric motor 64 remote from the floating caliper 46 , the coupling disk 36 of the magnetic brake 10 is press-fitted onto the shaft 38 of the electric motor 64 in a manner fixed against relative rotation.
The function of the wheel braking device 44 of the invention is as follows: For actuation, the spindle nut 54 is driven by the electric motor 64 to rotate in an actuating direction of rotation, so that the threaded spindle 56 is displaced translationally, axially in the direction of the brake disk 50 . The spline 74 of the floating caliper 46 prevents any rotation of the threaded spindle 56 . The threaded spindle 56 presses the friction brake lining 48 , mounted on its brake lining plate 72 , against one side of the brake disk 50 . Via a reaction force, the second wheel brake lining 48 is pressed against the other side of the brake disk 50 in a manner known per se via the floating caliper 46 . The brake disk 50 is braked, and a braking force or braking moment is proportional to the driving moment brought to bear by the electric motor 64 .
To release the wheel braking device 44 or to reduce the braking force, the spindle nut 54 is driven in the opposite, restoring direction of rotation, and as a result the threaded spindle 56 is moved translationally away from the brake disk 50 . The friction wheel lining mounted on its brake lining plate 72 is lifted from the brake disk 50 . The threaded spindle 56 is restored far enough that a gap between the friction wheel linings 48 and the brake disk 50 , which gap remains regardless of any wear of the friction brake linings 48 , exists when the wheel braking device 44 is not actuated; the so-called “air play” of the wheel braking device 44 of the invention remains constant.
During the actuation and release of the wheel braking device 44 , the magnetic brake 10 is in its released position, so that the shaft 38 of the electric motor 64 is freely rotatable. When the wheel braking device 44 is used as a parking brake, the wheel braking device 44 is actuated, so that the brake disk 50 is held in a manner fixed against relative rotation between the friction brake linings 48 . Next, by supplying current to one of its two electromagnets 18 , 20 ; 18 , 22 , the magnetic brake 10 is switched over into its braking position, and in this way the shaft 38 of the electric motor 64 is blocked, and as a result the wheel braking device 44 is locked, and the braking force once brought to bear is maintained while the electric motor 64 and the magnetic brake 10 are without current. Also, when the wheel braking device 44 is used as a service brake, if a braking force exerted on the brake disk 50 is temporarily kept constant, this can be done by providing that after the braking force is brought to bear, the magnetic brake 10 is switched over to its braking position with the electric motor 64 ; all that is required is a brief current pulse to one of its two electromagnets 18 , 20 ; 18 , 22 . The braking force is as a result kept constant without supplying current to the electric motor 64 and without supplying current to the magnetic brake 10 . For varying the braking force, the magnetic brake 10 is switched over to its released position. In this way, the electric motor 64 is supplied with current only in order to vary the braking force and in particular in order to increase the braking force. On the one hand, this saves energy and relieves an on-board electrical system of a vehicle that can be braked with the wheel braking device 44 . On the other, hand heating of the electric motor 64 is reduced, since the electric motor is supplied with current only for varying the braking force but when the braking force is being kept constant is currentless. Hence there is less of a load on the electric motor 64 , and accordingly a less powerful and thus smaller, lighter electric motor 64 can be used.
In the case of a defect, that is, if an electronic control system of the electric motor 64 , its power supply, or the electric motor 64 itself fails, the magnetic brake 10 is switched to its released position, so that the shaft 38 of the electric motor 64 is freely rotatable. As a result, the threaded nut 54 is also freely rotatable. The threaded spindle 56 is forced axially away from the brake disk 50 by the friction brake lining 48 pressed against the brake disk 50 , and since the spindle drive 52 is non-self-locking, the threaded spindle sets the spindle nut 54 into rotation. The wheel braking device 44 is released, until the contact pressure force of the friction brake linings 48 against the brake disk is so slight that the threaded spindle 56 does not move any further, because of internal friction of the spindle drive 52 , the bevel gear system 66 , 68 , and the electric motor 64 . The friction brake linings 48 rest on the brake disk 50 with a negligible residual force that is so slight that the brake disk 50 is virtually freely rotatable, and a motor vehicle equipped with the wheel braking device 10 can be driven without causing overheating of the wheel braking device 44 . It is understood that the magnetic brake 10 can be disposed at some other point in the wheel braking device 44 instead, and can for instance lock the spindle nut 54 in a directly releasable way (not shown).
The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims. | The invention relates to a preferably bistable magnetic brake, which is intended in particular for locking an actuating device of an electromechanical wheel braking device in its braking position at a given time. To enable releasing the magnetic brake even in the event of a defect, the invention proposes embodying the magnetic brake with two redundant electromagnets for its actuation. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to an enlarged pattern generator for enlarging original dot matrix patterns of characters and symbols.
Together with the recent development in document processing technologies, characters of not only one size but of many sizes are frequently required now. It is extremely uneconomical, however, to store all these required character patterns individually because this will have the consequence of requiring an unnecessarily large storage space. In order to eliminate this problem, there has been developed a method according to which only a certain standard dot pattern is retained as the original and patterns of desired sizes are obtained by making enlargements of this standard pattern. By this method, however, characters which were simply enlarged proportionally from the original usually do not look natural because the intervals between lines or dots which form the pattern are also magnified. This is illustrated by FIGS. 6(a) and 6(b) which show an original pattern and an enlarged pattern, respectively.
In order to overcome this problem, use has been made of a method of adding extra dots (in the case of a pattern formed by dots) so as to fill such intervals. By this method, however, enlarged characters still frequently fail to look natural because some of the dots are added into areas where corrections are not needed.
It is therefore an object of this invention to provide an enlarged pattern generator which, when generating an enlarged pattern from a standard dot matrix pattern, makes pattern corrections not by adding dots but by deleting them.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1(a) and 1(b) show by an example the principle the dot pattern processing according to the present invention.
FIGS. 2(a), 2(a'), 2(b), 2(b'), 2(c), 2(c'), 2(d) and 2(d') show how corrections are made according to the present invention.
FIG. 3 is a block diagram of a circuit for the operation of the present invention.
FIGS. 4(a), 4(b), 4(c) and 4(d) explain the logical operations of the gate circuit shown in FIG. 3.
FIGS. 5(a) and 5(b) show the effects of pattern enlargement by the method of the present invention.
FIGS. 6(a) and 6(b) show an example of pattern enlargement by a conventional method.
DESCRIPTION OF THE INVENTION
The principle of the method of the present invention will be explained by an example wherein dots are arranged in rectangular arrays in the mode of a square matrix. Let us suppose that some of the dots are "not illuminated" (dark) while the others are "illuminated" (bright) to describe a pattern. FIG. 1(a) shows an example of such a rectangular array (or matrix) of 30 dots, each represented by a dot number N (N being an integer between 1 and 30). Of these 30 dots, those with numbers enclosed in a square are intended to represent bright dots.
FIG. 1(b) is an enlarged matrix of dots corresponding to that of FIG. 1(a). A double-width, double-height enlargement is considered so that each dot N in the original matrix of FIG. 1(a) is now represented by 4 dots N-1, N-2, N-3 and N-4 in the enlarged matrix of FIG. 1(b). According to the conventional method described above, all 4 dots in the enlarged matrix corresponding to a bright dot in the original matrix (such as N=1 of FIG. 1(a)) would be "illuminated" and hence bright. According to the method of the present invention, however, not all of the 4 dots in the enlarged matrix corresponding to a bright dot in the original pattern are necessarily bright. Depending on the pattern, one or more of such 4 dots are made dark. In what follows, such dots on the enlarged matrix which would be bright according to the conventional method because they correspond to a bright dot in the original matrix but are made dark according to the method of the present invention, will be referred to as "corrected" dots, and the operation of keeping such dots dark in the enlarged matrix may be called "correction". Such corrected dots are identified on FIG. 1(b) by numbers surrounded by dotted lines. In both FIGS. 1(a) and (b), numbers not surrounded by lines represent dark dots.
FIG. 2 shows 3×3 matrices by means of which dots to be "corrected" are identified. The center element of each 3×3 matrix represent the status (dark or bright) of a dot in the original matrix of FIG. 1(a). The remaining eight elements show whether its eight neighboring dots (left-above, left, left-below, above, below, right-above, right and right-below) are bright or dark and this information determines whether the 4 dots corresponding to the bright dot of the original dot pattern represented by the center element should be allowed to remain bright (uncorrected) or be made dark (corrected).
If the bits representing the status of the 3 neighboring dots at the "left", "left-above" and "above" of one of the bright dots on the original pattern are all "0" (dark) as shown in FIG. 2(a), for example, the dot N-1 at "left-above" is made dark ("0") on the enlarged pattern as shown in FIG. 2(a'). Similarly, if the 3 neighboring dots "above", "right-above" and "right" are as shown in FIG. 2(b) the dot N-2 at "right-above" is made dark ("0") as shown in FIG. 2(b'). Situations of FIG. 2(c) and FIG. 2(d) respectively result in FIG. 2(c') and FIG. 2(d') on the enlarged pattern.
FIG. 3 shows a block diagram of a circuit which works out the correction logic of FIG. 2. The circuit comprises, as shown in FIG. 3, a clock and timing generator circuit, a character pattern memory 31, a shift register 32 adapted to store 3 lines of the character pattern, a three-bit shift register 33 of "serial-input and parallel-output" type for forming a correction matrix, a gate circuit 34 for determining a corrected pattern from the output of said three-bit shift register 33 and an output register 35 for the enlarged dot pattern with corrections according to the present invention.
FIG. 4 shows the logical circuits in the gate circuit 34 of FIG. 3 which, given the bit information a 0 , a 1 , a 2 , . . . a 8 , output the negative logical products (NOT-AND) as follows: a 1 .a 8 .a 7 as shown by FIG. 4(a), a 5 .a 6 .a 7 as shown by FIG. 4 (b), a 1 .a 2 .a 3 as shown by FIG. 4(c) and a 3 .a 4 .a 5 as shown by FIG. 4(d).
The original dot pattern shown by FIG. 1(a) is stored in the character pattern memory 31 and is transmitted by the timing generating circuit 30 to the shift register 32 in the order of dots 1, 2, 3, . . . , 29, 30. It will be assumed here that one-bit information "1" and "0" corresponds to each bright and dark dot, respectively. The shift register 32 is of sufficient length for storing three lines of the dot pattern and the output of the shift register 32 corresponding to each line is connected to the shift register 33 for forming a correction matrix. The information on dots 1, 2, . . . , 30 of the original pattern transmitted to the shift register 32 is successively shifted. After ten shifts corresponding to one line, the information on dot 1 reaches a 2 of the register 33. After twenty-two additional shifts, information on dots 1, 2, 10, 11 and 12 are stored in a 0 , a 1 , a 2 , a 3 and a 4 , respectively.
In this situation, a 5 , a 6 and a 7 are all "0" so that a 5 .a 6 .a 7 =1. This corresponds to FIG. 2(b) and hence the dot at right-above will not be illuminated (dark) as shown by FIG. 2(b'). Similarly, a 3 .a 4 .a 5 =1 corresponding to FIG. 2(d) and hence the dot at right-below remains dark as shown by FIG. 2(d').
By contrast, information "1" on dot 2 is in a 1 and information "1" on dot 12 is in a 2 of the register 33 so that a 1 .a 8 .a 7 =a 1 .a 2 .a 3 =0. Thus the four dots 1-1, 1-2, 1-3 and 1-4 on the enlarged pattern corresponding to dot 1 of the original pattern have "0", "1", "0" and "1", respectively and they are inputted into the output register 35. An output pattern device (not shown) is connected to the output register 35 and the pattern dots with bit information "1" are caused to remain dark, thus effecting the desired "corrections" according to the present invention. Similarly, dots 1-1, 1-3, 3-2, 8-1, 8-2, 12-3, 17-1, etc. surrounded by broken lines on the enlarged pattern of FIG. 1(b) are prevented from becoming "bright."
FIG. 5 illustrates the effects of these corrections by showing an original dot pattern (FIG. 5(a)) and its enlarged pattern (FIG. 5(b)). A comparison between FIG. 5(b) and FIG. 6(b) makes it clear that the character looks much more natural with the corrections according to the present invention.
This invention is applicable to double-width-and-height printing by a word processor and also to other types of character pattern printers such as laser printers. As described, an enlarged character generator of this invention can operate swiftly by means of a simple circuit structure and make visual recognition of characters and symbols easier by making characters appear smoother and hence more natural. | An enlarged pattern generator generates an enlarged dot matrix pattern from an original dot matrix pattern by providing up to four mutually adjacent dots. Presence and absence of neighboring dots are examined regarding each dot in the original dot matrix pattern in order to determine whether less than four dots should be provided in the enlarged pattern corresponding thereto. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a game and more particularly to a game played on a board with movable pieces whose progress in the game is determined partly by chance and partly by skill.
This game is an adult level game. Up to six players, more if in teams, may conveniently play the game, deriving entertainment and knowledge therefrom. According to the game, a player progresses from start to finish on paths delineated on the surface of the game board, initially about the board's periphery and ending at the center of the board.
The prior art included various patents relating to identifying characters in a game. More particularly, U.S. Pat. No. 4,315,627 to Schleget, et al, discloses a game board apparatus having a board with playing pieces, and a series of cards each relating to a public figure in various categories of activity. In the Schleget game, one player assumes the identity of a character which in turn is determined by a character card. The other players then question the first player attempting to determine his identity. Successful and unsuccessful guesses determine each player's general progression about the game board.
The present invention is similar in that a game board and playing pieces are used. However, character identification is by clues and clues are obtained as a function of various chance and tactical/strategic devices and methods. No one player portrays a character. The present invention uses multiple paths where the Schleget game uses only one. The present invention also contains multiple levels of clues and guesses, where the Schleget game uses only one, although different categories of characters may be used. The present invention eliminates much of the subjectivity inherent in the Schleget game and also introduces a greater element of chance.
SUMMARY OF THE INVENTION
By the present invention, a game board with start and finish blocks, and intermediate play blocks, is provided along with resumes and cards containing biographical clues to as well as the identity of different real and fictional characters. The resumes are stored in a clue box which contains clue windows for presenting the various clues contained on individual resumes. As the players move about the game board using a chance device to determine the number of spaces, clue windows are opened during each turn, revealing additional information about a particular character. During a later stage of the game, the cards are used, each one containing several clues about a particular character. During the game, the players compete to progress from the starting block to an end game block on the game board by identifying characters. Playing tokens are used to identify a player's location on the board in the course of playing the game. Chips are issued to individual players at various points in the game. The chips allow a player to obtain additional information about a particular character. Scoring pins are used to track the number of characters correctly identified by a player.
The differences between the Schleget game and the present invention become even more apparent. The present invention, to a greater degree than the Schleget game, is a learning, as well as an entertainment game. In Schleget, the questions and answers are limited by the shared knowledge of the players. It is conceivable that the person answering or questioning does not know anything about the character. With the present invention, the clues may provide the players with information they did not previously have, and/or with helpful information they would not have thought to ask for. The game is so structured that it almost guarantees that someone can finally identify the character. An important distinction between the two games lies in the availability of information about a character. In Schleget, it appears that all players automatically learn of all information developed. In the present invention, some players may use chips to obtain more information than others. This adds an important tactical/strategic element to the present invention not present in Schleget, i.e., the chips. Present invention players must decide when to use this source of information. Another important distinction lies in the fact that the present invention can be played by one person, i.e., playing against the clue box, while Schleget cannot.
For a better understanding of the invention, its advantages, and objectives obtained by its use, reference should be had to the drawings, which form a further part hereof, and to the accompanying descriptive matter, in which there is illustrated and described a preferred embodiment of the invention.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a game board according to the present invention;
FIG. 2 contains top plan views of the faces of resumes, showing the format of the entries contained thereon, and typical examples of real and fictional character resumes;
FIG. 3 is a perspective view of a clue box;
FIG. 4 contains top plan views of both sides of cards which are typical of those employed in the game;
FIG. 5 is a perspective view of a standard die;
FIG. 6 is a perspective view of typical tokens utilized by the various players in the game;
FIG. 7 is a perspective view of scoring pins alone and inserted in the token described in FIG. 6; and
FIG. 8 is a perspective view of a chip which is typical of those employed in the game.
DETAILED DESCRIPTION OF THE INVENTION
Referring more particularly to the drawings in detail, wherein like numerals indicate like elements, reference numeral 1 refers generally to a four-sided game board comprising the board apparatus of the invention. FIG. 1 shows in top plan view a game board 1 having a substantially square configuration. The game board 1 includes a plurality of marked blocks and spaces forming various paths from the Starting block 3, extending about the periphery of the game board 1, and branching off and finishing at the End Game block 4 in the center of the game board 1.
In this embodiment of the game, there are twenty-eight blocks forming a main track about the periphery of the board 1. At selected points about this main track, there are, in addition to the Starting block 3, Access to End Game blocks 10, a Free Roll block 5, a Lose A Turn block 6, and a Free Eyes Only Chip block 7. The Starting block 3 is at one corner of the board 1. Moving clock-wise about the main track, the next corner contains the Free Roll block 5; the next corner after that contains the Lose A Turn block 6; and the corner after that contains the Free Eyes Only Chip block 7. The third and fourth blocks in either direction of a corner block are Access To End Game blocks 10. The remaining blocks 2 are undesignated play blocks, not otherwise marked, and may contain any convenient markings, drawings, pictures, or other graphics.
Between the End Game block 4 in the center of the board 1 and each pair of Access To End Game blocks 10 are five, generally rectangular Step blocks forming separate paths between the End Game block 4 and each pair of Access To End Game blocks 10. The Step block nearest each pair of Access To End Game blocks 10 are termed Step One blocks 11. The Step blocks next to the Step One blocks 11 toward the End Game block 4 are termed Step Two blocks 12. The Step blocks next to the Step Two blocks 12 toward the End Game block 4 are termed Step Three blocks 13. The Step blocks next to the Step Three blocks 13 toward the End Game block 4 are termed Step Four blocks 14. The Step blocks next to the Step Four blocks 14 adjacent to the End Game block 4 are termed Step Five blocks 15.
FIG. 2 contains top plan views of the character resumes 20 used in this embodiment of the invention. The resume 20 format is shown in FIG. 2a. Each resume 20 has twenty entries on a side pertaining to a specific character. The first sixteen entries are Common Knowledge clues 21; the next three are Eyes Only clues 22; and the last entry is the Answer 23 identifying the character. The entries are arranged in two vertical rows 28 and 29 of ten entries each. The Common Knowledge clues 21 and the Eyes Only clues 22 are arranged so that ten of the Common Knowledge clues 21 fill the first vertical row 28. The six remaining Common Knowledge clues 21 are positioned in the first six entries of the second vertical row 29. The remaining four entries in the second vertical row 29 are filled first with the Eyes Only clues 22, and then the Answer 23. The Common Knowledge clues 21 and the Eyes Only clues 22 progress from the obscure (first Common Knowledge clue 24 and first Eyes Only clue 25) to the more obvious sixteenth Common Knowledge clue 26 and third Eyes Only clue 27). In this embodiment of the invention, each resume 20 is printed on a letter-size sheet of stiff paper. There are approximately four hundred resumes 20. FIG. 2b contains a sample resume 20 of a real character, and FIG. 2c shows a sample resume 20 of a fictional character.
The resumes 20 are stored in a container, termed a clue box 30. FIG. 3 contains a perspective view of a clue box 30. The clue box 30 has a generally rectangular shape with a depth sufficient to hold four hundred resumes 20. The longitudinal axis of the clue box 30 is positioned vertically. The clue box 30 is open at the top 34 so that the resumes 20, either singularly or as a whole, may be removed or inserted. The face 31 of the clue box 30 contains two vertical rows 38 and 39 of ten windows 32 each. The windows 32 have a generally rectangular shape, with the longitudinal axis positioned horizontally. The wondows 32 correspond to the entries 21, 22, and 23 on the resumes 20. In this embodiment of the invention, the windows 32 are opened and shut by hinged panels 33, one for each window 32. Other methods which could be used in place of hinged panels 33 include sliding panels, top-hinged panels, and bottom-hinged panels. The resumes 20 inside the clue box 30 and the windows 32 on the face 31 of the clue box 30 are so arranged that, when a window 32 is opened, a Common Knowledge Clue 21, Eyes Only Clue 22, or Answer 23 is revealed on the resume 20 immediately inside and against the face 31 of the clue box 30. Each window 32 is labeled, either on its panel 33 or to one side of the window 32, with a category, i.e., Common Knowledge Clue, Eyes Only Clue, or Answer.
FIG. 4 describes the cards, termed End Game cards 40, used in this embodiment of the game. One side 41 of the End Game card 40 (see FIG. 4a) contains three clues (obscure to less obscure) about a particular character as well as the name of the character. The reverse side 42 (see FIG. 4b) contains an identifier that the cards 40 are End Game cards. There are approximately two hundred cards 40 used in this embodiment of the game. Each card 40 has a generally rectangular shape with approximate dimensions of three and one-half inches by two and one-half inches.
FIG. 5 discloses the standard die 45 normally used to determine which player will commence play and the number of blocks a player may advance around the board 1. In lieu of the die 45, a spinner dial and card or any other convenient means for making the foregoing selections can be used whereby one player may receive a higher number than the other players.
Each player has a token 50 to identify his position on the board 1. The token may be any shape or size but must have the ability to hold three scoring pins 55 described below. FIG. 6 discloses a typical token 50 with holes 51 in the top 52 to hold scoring pins 55. Conveniently, the tokens 50 may be of different colors to distinguish one from another. Numbers, modified shapes, symbols, or other means may also be used, alone or in combination, to distinguish the various tokens 50.
FIG. 7 is a perspective view of the scoring pins 55 used in this embodiment of the game. The scoring pins 55, which may be made of any material, consist generally of a member 56 thick enough to grasp by a players fingers. This member 56 is either tapered or is attached to a thin, rod-like piece 57 by means of which the pin 55 may be attached to the token 50. The scoring pins 55 are disclosed alone and also inserted in the token 50 described in FIG. 6. This embodiment of the game uses approximately twenty-five scoring pins 55.
This invention also uses up to seventy-five chips 60 (see FIG. 8). The chips 60 are generally flat and disk shaped. They may be made of plastic or some other convenient material. Each chip 60 is approximately the size of a dime and is printed with an Eyes Only graphic, which should be similar to that used on the game board 1 and the clue box 30.
OPERATION
The object of the game is for one of a plurality of players, each represented by a token 50 and beginning at the Start block 3, to reach the End Game block 4 at the center of the game board 1, by correctly identifying the real or fictional characters whose biographical information appears on resumes 20 and End Game cards 40. The clues to each character's identity fall into two categories, i.e., Common Knowledge clues 21 and Eyes Only clues 22. The clues are contained on resumes 20 and End Game cards 40 and begin with obscure data and progress to more obvious information.
At the beginning of the game, all of the resumes 20 are placed in the clue box 30. The clue box windows 32 are all closed. Each player is given a token 50 and three Eyes Only chips 60. The chips 60 are used by a player to buy Eyes Only clues 22 when it is his turn. Additional chips 60 may be obtained by landing on the game board's Free Eyes Only Chip block 7 or by correctly identifying a character on a resume 20. The players' tokens 50 are all placed on the Start block 3. The die 45 is thrown by each player and the one receiving the highest number goes first. The remaining order of players may be in accordance with their numbers thrown on the die 45 or clock-wise from the first player.
The first player moves from the Start block 3 clock-wise around the board 1 a number of blocks equal to the number thrown on the die 45. At this point in the game, all players are confined to the main track blocks about the periphery of the board 1. Landing on any block except the Lose A Turn block 6 entitles that player to open a clue box window 32. The window 32 opened must be a Common Knowledge window and must be opened in sequence starting with Common Knowledge #1 37. None can be skipped. All players may look at the information revealed on the resume 20 entry appearing in the opened window 32. Once a Common Knowledge window is opened, it stays open until the resume Answer 23 is correctly guessed. Players may guess only when it is their turn.
The player whose turn it is now has three options: guess the character's identity; use one or more of his Eyes Only chips 60 to buy Eyes Only clues 22, one clue per chip; or pass the die 45 to the player whose turn is next without guessing. If the player chooses to guess, he must either announce his guess to the other players or write it down where the other players cannot see it. He alone then looks at the Answer 23 under the last window 32 and announces whether he is right or wrong. The player may choose to write his guess if he feels that the other players would be helped by a known wrong guess. A written guess must be revealed to the other players only if the guesser claims to have answered correctly. If the player admits he guessed wrong, he need not reveal his written guess. If the player's guess is wrong, he does not receive another turn until this particular character's identity is correctly guessed or a new character resume 20 is put into play. His token 50 is left on the block on which he was when he made the incorrect guess. If the guess is correct, the player is given a scoring pin 55, which he inserts or attaches to his token 50, and an Eyes Only chip 60. The player retains control of the die 45, the windows 32 of the clue box 30 are closed, and the old resume 20 is removed and positioned at the back of the resume pack. A new resume 20 is now positioned against the inside of the clue box face 31.
If the player had elected to buy one or more Eyes Only clues 22, he would be required to start with the first Eyes Only Window (#1), revealing the first Eyes Only clue 25, and proceed in sequence to the third 27. The Eyes Only clues 22 may only be seen by the player or players buying them. The Eyes Only windows 32 are closed after the player entitled to do so has looked at them. The player may then guess the identity of the character with the same consequences as described above, or he could pass the die 45 to the next player.
If a player lands on the Free Roll block 5, he obtains a free turn. By landing on the Lose A Turn block 6, he loses a turn and must immediately pass the die 45. As stated above, landing on the Free Eyes Only Chip block 7 entitles the player to an additional chip 60. At this point in the game, the Access To End Game blocks 10 have no special meaning and merely comprise play blocks in the main track.
Play continues until the character's identity is established or until all players give up on the character. If one player is left in a given character round, he may look at all the Common Knowledge clues 21 free, but may look at the Eyes Only clues 22 only if he buys them. Once a character is correctly identified, or all of the players give up, the clue box windows 32 are all closed. The used resume 20 is moved to the back 36 of the clue box 30. A new resume 20 will then be positioned behind the clue box widows 32.
When a player has obtained three scoring pins 55 by correctly identifying three characters over the course of the game, he proceeds to End Game. After identifying the third character, the player has one roll of the die 45 to reach the nearest Step One block 11 (always moving in a clock-wise direction). A Step One block 11 must be approached from an Access To End Game block 10 and not diagonally from another block 2. If the roll of the die 45 is insufficient to take the player to a Step One block 11, the player must pass the die 45 and wait until his next turn before rolling the die 45 again. If the roll exceeds the number needed, he must still stop on the Step One block 11. Another player draws an End Game card 40 and reads to him the first clue on the End Game card 40. The End Game player may guess the character's identity after the first clue, or ask for the second clue and then guess, or even ask for the third clue and then guess. If the End Game player guesses wrong at any point, he must wait until his next turn to continue play. If he guesses correctly after the first clue, he advances three steps. If he guesses correctly after the second clue, he advances two steps. If he guesses correctly after the third clue, he advances one step. The End Game player retains his turn until he either guesses wrong or cannot identify an End Game character after the third clue on the End Game card 40. He must then wait for his next turn. The first player to reach End Game block 4 wins the game.
It is understood that the above-described embodiment is merely illustrative of the application. The basic teachings of the present invention have been described above. Many extensions and variations will be obvious to one having ordinary skill in the art. Many, if not all of the physical aspects of the game are flexible, i.e., number of blocks, dimensions, colors, etc. The number of resumes 20 and End Game cards 40 may be increased and even sub-divided into topical categories. Other embodiments may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof. | A competitive character identification game comprising a game board with start and finish blocks, and intermediate play blocks, along with resumes and cards containing biographical clues to as well as the identity of different real and fictional characters. The resumes are stored in a clue box which contains clue windows for presenting the various clues contained on individual resumes. As the players move about the game board using a chance device to determine the number of spaces, clue windows are opened during each turn, revealing additional information about a particular character. During a later stage of the game, the cards are used, each one containing several clues about a particular character. During the game, the players compete to progress from the starting block to an end game block on the game board by identifying characters. Playing tokens are used to identify a player's location on the board in the course of playing the game. Chips are issued to individual players at various points in the game. The chips allow a player to obtain additional information about a particular character. Scoring pins are used to track the number of characters correctly identified by a player. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of co-pending application Ser. No. 09/501,467, filed Feb. 9, 2000, which is a continuation-in-part of Ser. No. 09/350,620, filed on Jul. 7, 1999, which is a continuation-in-part of Ser. No. 09/335,257, filed on Jun. 17, 1999; this application is also a continuation-in-part of co-pending application Ser. No. 09/406,264, filed on Sep. 24, 1999. These parent, grand-parent, and great-grandparent applications are herein entirely incorporated by reference.
FIELD OF THE INVENTION
[0002] All U.S. Patents cited herein are entirely incorporated by reference.
[0003] This invention relates generally to coated inflatable fabrics and more particularly concerns airbag cushions to which very low add-on amounts of coating have been applied and which exhibit extremely low air permeability. The inventive inflatable fabrics are primarily for use in automotive restraint cushions that require low permeability characteristics (such as side curtain airbags). Traditionally, heavy, and thus expensive, coatings of compounds such as neoprene, silicones and the like, have been utilized to provide such required low permeability. The inventive fabric utilizes an inexpensive, very thin coating to provide such necessarily low permeability levels. Thus, the inventive coated inflatable airbag possesses a coating comprising an elastomeric material (or materials) in contact with the target fabric wherein the elastomeric material possesses a tensile strength of at least 2,000 psi and an elongation at break of at least 180%. The coating is then applied to the airbag surface in an amount of at most 3.0 ounces per square yard (and preferably forms a film). The inventive airbag exhibits a characteristic leak-down time (defined as the ratio of inflated bag volume to bag volumetric leakage rate at 10 psi) of at least 5 seconds after inflation. The resultant airbag cushions, particularly low permeability cushions exhibiting very low rolled packing volumes, are intended to reside within the scope of this invention.
BACKGROUND OF THE PRIOR ART
[0004] Airbags for motor vehicles are known and have been used for a substantial period of time. A typical construction material for airbags has been a polyester or nylon fabric, coated with an elastomer such as neoprene, or silicone. The fabric used in such bags is typically a woven fabric formed from synthetic yarn by weaving practices that are well known in the art.
[0005] The coated material has found acceptance because it acts as an impermeable barrier to the inflation medium. This inflation medium is generally a nitrogen or helium gas generated from a gas generator or inflator. Such gas is conveyed into the cushion at a relatively warm temperature. The coating obstructs the permeation of the fabric by such gas, thereby permitting the cushion to rapidly inflate without undue decompression during a collision event.
[0006] Airbags may also be formed from uncoated fabric which has been woven in a manner that creates a product possessing low permeability or from fabric that has undergone treatment such as calendaring to reduce permeability. Fabrics which reduce air permeability by calendaring or other mechanical treatments after weaving are disclosed in U.S. Pat. Nos. 4,921,735; 4,977,016; and 5,073,418 (all incorporated herein by reference).
[0007] Silicone coatings typically utilize either solvent based or complex two component reaction systems. Dry coating weights for silicone have been in the range of about 3 to 4 ounces per square yard or greater for both the front and back panels of side curtain airbags. As will be appreciated by one of ordinary skill in this art, high add on weights substantially increase the cost of the base fabric for the airbag and make packing within small airbag modules very difficult. Furthermore, silicone exhibits very low tensile strength characteristics that do not withstand high pressure inflation easily without the utilization of very thick coatings.
[0008] The use of a particular type of polyurethane as a coating as disclosed in U.S. Pat. No. 5,110,666 to Menzel et al. (herein incorporated by reference) permits low add on weights reported to be in the range of 0.1 to 1 ounces per square yard but the material itself is relatively expensive and is believed to require relatively complex compounding and application procedures due to the nature of the coating materials. Patentees, however, fails to disclose any pertinent elasticity and/or tensile strength characteristics of their particular polyurethane coating materials. Furthermore, there is no discussion pertaining to the importance of the coating ability (and thus correlated low air permeability) at low add-on weights of such polyurethane materials on side curtain airbags either only for fabrics which are utilized within driver or passenger side cushions. All airbags must be inflatable extremely quickly; upon sensing a collision, in fact, airbags usually reach peak pressures within 10 to 20 milliseconds. Regular driver side and passenger side air bags are designed to withstand this enormous inflation pressure; however, they also deflate very quickly in order to effectively absorb the energy from the vehicle occupant hitting the bag. Such driver and passenger side cushions (airbags) are thus made from low permeability fabric, but they also deflate quickly at connecting seams (which are not coated to prevent air leakage) or through vent holes. Furthermore, the low add-on coatings taught within Menzel, and within U.S. Pat. No. 5,945,186 to Li et al., would not provide long-term gas retention; they would actually not withstand the prolonged and continuous pressures supplied by activated inflators for more than about 2 seconds, at the most. The low permeability of these airbag fabrics thus aid in providing a small degree of sustained gas retention within driver and passenger airbag cushions to provide the deflating cushioning effects necessary for sufficient collision protection. Such airbag fabrics would not function well with side curtain airbags, since, at the very least, the connecting seams which create the pillowed, cushioned structures within such airbags, as discussed in greater detail below, would exhibit too high a leakage rate upon inflation at requisite high gas pressures. As these areas provide the greatest degree of leakage during and after inflation, the aforementioned patented low coating low permeability airbag fabrics would not be properly utilized within side curtain airbags, in particular side curtain airbags intended to provide extended rollover protection.
[0009] As alluded to above, there are three primary types of different airbags, each for different end uses. For example, driver-side airbags are generally mounted within steering columns and exhibit relatively high air permeabilities in order to act more as a cushion for the driver upon impact. Passenger-side airbags also comprise relatively high air permeability fabrics which permit release of gas either therethrough or through vents integrated therein. Both of these types of airbags are designed to protect persons in sudden collisions and generally burst out of packing modules from either a steering column or dashboard (and thus have multiple “sides”). Side curtain airbags, however, have been designed primarily to protect passengers during side crashes provide rollover protection by retaining their inflation state for a long duration, and generally unroll from packing containers stored within the roofline along the side windows of an automobile (and thus have a back and front side only). Side curtain airbags therefore not only provide cushioning effects but also provide protection from broken glass and other debris. As such, it is imperative that side curtain airbags, as noted above, retain large amounts of gas, as well as high gas pressures, to remain inflated throughout the longer time periods of the entire potential rollover situation. To accomplish this, these side curtains are generally coated with very large amounts of sealing materials on both the front and back sides. Since most side curtain airbag fabrics comprise woven blanks that are either sewn, sealed, or integrally woven together, discrete areas of potentially high leakage of gas are prevalent, particularly at and around the seams. It has been accepted as a requirement that heavy coatings were necessary to provide the low permeability (and thus high leak-down time) necessary for side curtain airbags. Without such heavy coatings, such airbags would most likely deflate too quickly and thus would not function properly during a rollover collision. As will be well understood by one of ordinary skill in this art, such heavy coatings add great cost to the overall manufacture of the target side curtain airbags. There is thus a great need to manufacture low permeability side curtain airbags with less expensive (preferably lower coating add-on weight) coatings without losing the aging, stability, and permeability characteristics necessary for proper functioning upon deployment. To date, there has been little accomplished, if anything at all, alleviating the need for such thick and heavy airbag coatings from side curtain airbags.
[0010] Furthermore, there is a current drive to store such low permeability side curtain airbags within very thin, preferably, though not necessarily, cylindrically shaped modules. Since these airbags are generally stored within the rooflines of automobiles, and the area available is quite limited, there is always a great need to restrict the packing volume of such restraint cushions to their absolute minimum. However, the previously practiced low permeability side curtain airbags have proven to be very cumbersome to store in such cylindrically shaped containers at the target automobile's roofline. The actual time and energy required to roll such heavily coated low permeability articles as well as the packing volume itself, has been very difficult to reduce. Furthermore, with such heavy coatings utilized, the problems of blocking (i.e., adhering together of the different coated portions of the cushion) are amplified when such articles are so closely packed together. The chances of delayed unrolling during inflation are raised when the potential for blocking is present. Thus, a very closely packed, low packing volume, low blocking side curtain low permeability airbag is highly desirable. Unfortunately, the prior art has again not accorded such an advancement to the airbag industry.
OBJECTS AND BRIEF DESCRIPTION OF THE INVENTION
[0011] In light of the background above, it can be readily seen that there exists a need for a low permeability, side curtain airbag that utilizes lower, and thus less expensive, amounts of coating, and therefore exhibits a substantially reduced packing volume over the standard low permeability type side curtain airbags. Such a coated low permeability airbag must provide a necessarily long leak-down time upon inflation and after long-term storage. Such a novel airbag and a novel coating formulation provides marked improvements over the more expensive, much higher add-on airbag coatings (and resultant airbag articles) utilized in the past.
[0012] It is therefore an object of this invention to provide a coated airbag, wherein the coating is present in a very low add-on weight, possessing extremely high leak-down time characteristics after inflation and thus complementary low permeability characteristics. Another object of the invention is to provide an inexpensive side curtain airbag cushion. A further object of this invention is to provide an highly effective airbag coating formulation which may be applied in very low add-on amounts to obtain extremely low permeability airbag structures after inflation. An additional object of this invention is to provide an airbag coating formulation which not only provides beneficial and long-term low permeability, but also exhibits excellent long-term storage stability (through heat aging and humidity aging testing). Yet another object of the invention is to provide a low permeability side curtain airbag possessing a very low rolled packing volume and non-blocking characteristics for effective long-term storage within the roofline of an automobile.
[0013] Accordingly, this invention is directed to an airbag cushion comprising a coated fabric, wherein said fabric is coated with an elastomeric composition in an amount of at most 3.0 ounces per square yard of the fabric; and wherein said airbag cushion, after long-term storage, exhibits a characteristic leak-down time of at least 5 seconds. Also, this invention concerns an airbag cushion comprising a coated fabric, wherein said fabric is coated with an elastomeric composition; wherein said elastomeric composition comprises at least one elastomer possessing a tensile strength of at least 2,000 psi and an elongation of at least 180%; and wherein said airbag cushion, after long-term storage, exhibits a characteristics leak-down time of at least 5 seconds. Additionally, this invention encompasses a coated airbag cushion which exhibits a packing volume factor (measured as the rolled diameter of the airbag cushion divided by the measured depth of coverage measured from the attachment point of the target automobile's roofline to lowest point of coverage below the roofline after inflation) of at most 0.05.
[0014] The term “characteristic leak-down time” is intended to encompass the measurement of time required for the entire amount of inflation gas introduced within an already-inflated (to a peak initial pressure which “opens” up the areas of weak sealing) and deflated airbag cushion upon subsequent re-inflation at a constant pressure at 10 psi. It is well known and well understood within the airbag art, and particularly concerning side curtain (low permeability) airbag cushions, that retention of inflation gas for long periods of time is of utmost importance during a collision that results in rollover and other subsequent problems. Side curtain airbags are designed to inflate as quickly as driver- and passenger-side bags, but they must deflate very slowly to protect the occupants during roll over and side impact. Thus, it is imperative that the bag exhibit a very low leakage rate after the bag experiences peak pressure during the instantaneous, quick inflation. Hence, the coating on the bag must be strong enough to withstand the shock and stresses when the bag is inflated so quickly. Thus, a high characteristic leak-down time measurement is paramount in order to retain the maximum amount of beneficial cushioning gas within the inflated airbag. Airbag leakage after inflation (and after peak pressure is reached) is therefore closely related to actual pressure retention characteristics. The pressure retention characteristics (hereinafter referred to as “leak-down time”) of already-inflated and deflated side curtain airbags can be described by a characteristic leak-down time t, wherein:
t ( second ) = Bag volume ( ft 3 ) Volumetric leakage rate ( SCFH *) at 10 Psi × 3600
[0015] *SCFH: standard cubic feet per hour. It is understood that the 10 psi constant is not a limitation to the invention; but merely the constant pressure at which the leak-down time measurements are made. Thus, even if the pressure is above or below this amount during actual inflation or after initial pressurizing of the airbag, the only limitation is that if one of ordinary skill in the art were to measure the bag volume and divide that by the volumetric leakage rate (at 10 psi), the resultant measurement in time would be at least 5 seconds. Preferably, this time is greater than about 9 seconds; more preferably, greater than about 15 seconds; and most preferably, greater than about 20 seconds.
[0016] Likewise, the term, “after long-term storage” encompasses either the actual storage of an inventive airbag cushion within an inflator assembly (module) within an automobile, and/or in a storage facility awaiting installation. Furthermore, this term also encompasses any storage which is intended to simulate such long-term storage (through oven-aging, as one example) as well. Such a measurement is generally accepted, and is well understood and appreciated by the ordinarily skilled artisan, to be made through comparable analysis after representative heat and humidity aging tests. These tests generally involve 107° C. oven aging for 400 hours, followed by 83° C. and 95% relative humidity aging for a subsequent 400 hours and are universally accepted as proper estimations of the conditions of long-term storage for airbag cushions. Thus, this term encompasses such measurement tests. The inventive airbag fabrics must exhibit proper characteristic leak-down times after undergoing such rigorous pseudo-storage testing.
[0017] The inventive elastomeric coating composition must comprise at least one elastomer that possesses a tensile strength of at least 2,000 psi and an elongation to break of greater than about 180%. Preferably, the tensile strength is at least 3,000 psi, more preferably, 4,000, and most preferably at least about 6,000 (the high end is basically the highest one can produce which can still adhere to a fabric surface). The preferred elongation to break is more than about 200%, more preferably more than about 300%, and most preferably more than about 600%. These characteristics of the elastomer translate to a coating that is both very strong (and thus will withstand enormous pressures both at inflation and during the time after inflation and will not easily break) and can stretch to compensate for such large inflation, etc., pressures. Thus, when applied at the seams of a side curtain airbag, as well as over the rest of the airbag structure, the coating will most preferably (though not necessarily) form a continuous film. This coating acts to both fill the individual holes between the woven yarns and/or stitches, etc., as well as to “cement” the individual yarns in place. During inflation, then, the coating prevents leakage through the interstitial spaces between the yarns and aids in preventing yarn shifting (which may create larger spaces for possible gas escape).
[0018] The utilization of such high tensile strength and high elongation at break components permits the consequent utilization, surprisingly, of extremely low add-on weight amounts of such coating formulations. Normally, the required coatings on side curtain airbags are very high, at least 3.0 ounces per square yard (with the standard actually much higher than that, at about 4.0). The inventive airbag cushions require at most 3.0 (preferably less, such as 2.0, more preferably 1.8, still more preferably, about 1.5, and most preferably, as low as 0.8) ounces per square yard of this inventive coating to effectuate the desired high leak-down (low permeability). Furthermore, the past coatings were required to exhibit excellent heat and humidity aging stability. Unexpectedly, even at such low add-on amounts, and particularly with historically questionable coating materials (polyurethanes, for example), the inventive coatings, and consequently, the inventive coated airbag cushions, exhibit excellent heat aging and humidity aging characteristics. Thus, the coating compositions and coated airbags are clearly improvements within this specific airbag art.
[0019] Of particular interest as the elastomer components within the inventive elastomeric compositions are, specifically, polyamides, polyurethanes, acrylic elastomers, hydrogenated nitrile rubbers (i.e., hydrogenated NBR), fluoroelastomers (i.e., fluoropolymers and copolymers containing fluoro-monomers), ethylene-vinylacetate copolymers, and ethylene acrylate copolymers. Also, such elastomers may or may not be cross-linked on the airbag surface. Preferably, the elastomer is a polyurethane and most preferably is a polycarbonate polyurethane elastomer. Such a compound is available from Bayer Corporaiton under the tradename Impranil®, including Impranil® 85 UD, ELH, and EHC-01. Other acceptable polyurethanes include Bayhydrol® 123, also from Bayer; Ru 41-710, EX 51-550, and Ru 40-350, both from Stahl USA. Any polyurethane, or elastomer, for that matter, which exhibits the same tensile strength and elongation at break characteristics as noted above, however, are potentially available within the inventive coating formulation and thus on the inventive coated airbag cushion. In order to provide the desired leak-down times at long-term storage, however, the add-on weights of other available elastomers may be greater than others. However, the upper limit of 3.0 ounces per square yard should not be exceeded to meet this invention. The desired elastomers may be added in multiple layers if desired as long the required thickness for the overall coating is not exceeded. Alternatively, the multiple layer coating system may also be utilized as long as at least one elastomer possessing the desired tensile strength and elongation at break is utilized. In particular, such a coating system may include, as one example, a polyurethane-based bottom layer (for good tensile strength for low air permeability)(with an optional adhesion promoter present between the layer and the fabric) and a second layer of silicone (to provide excellent aging resistance, for example). Other types of such multiple coating systems are disclosed within grand-parent application Ser. No. 09/350,620, above fully incorporated by reference.
[0020] Other possible components present within the elastomer coating composition are thickeners, antioxidants, flame retardants, coalescent agents, adhesion promoters, and colorants. In accordance with the potentially preferred practices of the present invention, a dispersion (either solvent- or water-borne, depending on the selected elastomer) of finely divided elastomeric resin is compounded, or present in a resin solution, with a thickener and a flame retardant to yield a compounded mix having a viscosity of about 8000 centipoise or greater. A polyurethane is potentially preferred, with a polycarbonate polyurethane, such as those noted above from Bayer and Stahl, most preferred. Other potential elastomeric resins include other polyurethanes, such as Witcobond™ 253 (35% solids), from Witco, and Sancure, from BFGoodrich, Cleveland, Ohio; hydrogenated NBR, such as Chemisat™ LCH-7335X (40% solids), from Goodyear Chemical, Akron, Ohio; EPDM, such as EP-603A rubber latex, from Lord Corporation, Erie, Pa.; butyl rubber, such as Butyl rubber latex BL-100, from Lord Corporation; and acrylic rubber (elastomers), such as HyCar™, from BFGoodrich. This list should not be understood as being all-inclusive, only exemplary of potential elastomers. Furthermore, the preferred elastomer will not include any silicone, due to the extremely low tensile strength (typically below about 1,500 psi) characteristics exhibited by such materials. However, in order to provide effective aging and non-blocking benefits, such components may be applied to the elastomeric composition as a topcoat as long as the add-on weight of the entire elastomer and topcoat does not exceed 3.0 ounces per square yard and the amount of silicone within the entire elastomer composition does not exceed 20% by weight. Additionally, certain elastomers comprising polyester or polyether segments or other similar components, may not be undesirable, particularly at very low add-on weights (i.e., 0.8-1.2 oz/yd 2 ) due to stability problems in heat and humidity aging (polyesters easily hydrolyze in humidity and polyethers easily oxidize in heat); however, such elastomers may be utilized in higher add-on amounts as long, again, as the 3.0 ounces per square yard is not exceeded.
[0021] Among the other additives particularly preferred within this elastomer composition are heat stabilizers, flame retardants, primer adhesives, and materials for protective topcoats. A potentially preferred thickener is marketed under the trade designation NATROSOL™ 250 HHXR by the Aqualon division of Hercules Corporation which is believed to have a place of business at Wilmington, Del. In order to meet Federal Motor Vehicle Safety Standard 302 flame retardant requirements for the automotive industry, a flame retardant is also preferably added to the compounded mix. One potentially preferred flame retardant is AMSPERSE F/R 51 marketed by Amspec Chemical Corporation which is believed to have a place of business at Gloucester City N.J. Primer adhesives may be utilized to facilitate adhesion between the surface of the target fabric and the elastomer itself. Thus, although it is preferable for the elastomer to be the sole component of the entire elastomer composition in contact with the fabric surface, it is possible to utilize adhesion promoters, such as isocyanates, epoxies, functional silanes, and other such resins with adhesive properties, without deleteriously effecting the ability of the elastomer to provide the desired low permeability for the target airbag cushion. A topcoat component, as with potential silicones, as noted above, may also be utilized to effectuate proper non-blocking characteristics to the target airbag cushion. Such a topcoat may perform various functions, including, but not limited to, improving aging of the elastomer (such as with silicone) or providing blocking resistance due to the adhesive nature of the coating materials (most noticeably with the preferred polyurethane polycarbonates).
[0022] Airbag fabrics must pass certain tests in order to be utilized within restraint systems. One such test is called a blocking test which indicates the force required to separate two portions of coated fabric from one another after prolonged storage in contact with each other (such as an airbag is stored). Laboratory analysis for blocking entails pressing together coated sides of two 2 inch by 2 inch swatches of airbag fabric at 5 psi at 100° C. for 7 days. If the force required to pull the two swatches apart after this time is greater than 50 grams, or the time required to separate the fabrics utilizing a 50 gram weight suspended from the bottom fabric layer is greater than 10 seconds, the coating fails the blocking test. Clearly, the lower the required separating shear force, the more favorable the coating. For improved blocking resistance (and thus the reduced chance of improper adhesion between the packed fabric portions), topcoat components may be utilized, such as talc, silica, silicate clays, and starch powders, as long as the add-on weight of the entire elastomer composition (including the topcoat) does not exceed 3.0 ounces per square yard (and preferably exists at a much lower level, about 1.5, for instance).
[0023] Two other tests which the specific coated airbag cushion must pass are the oven (heat) aging and humidity aging tests. Such tests also simulate the storage of an airbag fabric over a long period of time upon exposure at high temperatures and at relatively high humidities. These tests are actually used to analyze alterations of various different fabric properties after such a prolonged storage in a hot ventilated oven (>100°C.) (with or without humid conditions) for 2 or more weeks. For the purposes of this invention, this test was used basically to analyze the air permeability of the coated side curtain airbag by measuring the characteristic leak-down time (as discussed above, in detail). The initially produced and stored inventive airbag cushion should exhibit a characteristic leak-down time of greater than about 5 seconds (upon re-inflation at 10 psi gas pressure after the bag had previously been inflated to a peak pressure above about 15 psi and allowed to fully deflate) under such harsh storage conditions. Since polyurethanes, the preferred elastomers in this invention, may be deleteriously affected by high heat and humidity (though not as deleteriously as certain polyester and polyether-containing elastomers), it may be prudent to add certain components within a topcoat layer and/or within the elastomer itself. Antioxidants, antidegradants, and metal deactivators may be utilized for this purpose. Examples include, and are not intended to be limited to, Irganox® 1010 and Irganox® 565, both available from CIBA Specialty Chemicals. This topcoat may also provide additional protection against aging and thus may include topcoat aging improvement materials, such as, and not limited to, polyamides, NBR rubbers, EPDM rubbers, and the like, as long as the elastomer composition (including the topcoat) does not exceed the 3.0 ounces per square yard (preferably much less than that, about 1.5 at the most) of the add-on weight to the target fabric.
[0024] Other additives may be present within the elastomer composition, including, and not limited to, colorants, UV stabilizers, fillers, pigments, and crosslinking/curing agents, as are well known within this art.
[0025] The substrate to which the inventive elastomeric coatings are applied to form the airbag base fabric in accordance with the present invention is preferably a woven fabric formed from yarns comprising synthetic fibers, such as polyamides or polyesters. Such yarn preferably has a linear density of about 105 denier to about 840 denier, more preferably from about 210 to about 630 denier. Such yarns are preferably formed from multiple filaments wherein the filaments have linear densities of about 6 denier per filaments or less and most preferably about 4 denier per filament or less. In the more preferred embodiment such substrate fabric will be formed from fibers of nylon, and most preferred is nylon 6,6. It has been found that such polyamide materials exhibit particularly good adhesion and maintenance of resistance to hydrolysis when used in combination with the coating according to the present invention. Such substrate fabrics are preferably woven using fluid jet weaving machines as disclosed in U.S. Pat. Nos. 5,503,197 and 5,421,378 to Bower et al. (incorporated herein by reference). Such woven fabric will be hereinafter referred to as an airbag base fabric. As noted above, the inventive airbag must exhibit extremely low permeability and thus must be what is termed a “side curtain” airbag. As noted previously and extensively, such side curtain airbags (a.k.a., cushions) must retain a large amount of inflation gas during a collision in order to accord proper long-duration cushioning protection to passengers during rollover accidents. Any standard side curtain airbag may be utilized in combination with the low add-on coating to provide a product which exhibits the desired leak-down times as noted above. Most side curtain airbags are produced through labor-intensive sewing or stitching (or other manner) together two separate woven fabric blanks to form an inflatable structure. Furthermore, as is well understood by the ordinarily skilled artisan, such sewing, etc., is performed in strategic locations to form seams (connection points between fabric layers) which in turn produce discrete open areas into which inflation gasses may flow during inflation. Such open areas thus produce pillowed structures within the final inflated airbag cushion to provide more surface area during a collision, as well as provide strength to the bag itself in order to withstand the very high initial inflation pressures (and thus not explode during such an inflation event). Other side curtain airbag cushions exist which are of the one-piece woven variety. Basically, some inflatable airbags are produced through the simultaneous weaving of two separate layers of fabric which are joined together at certain strategic locations (again, to form the desired pillowed structures). Such cushions thus present seams of connection between the two layers. It is the presence of so many seams (in both multiple-piece and one-piece woven bags) which create the aforementioned problems of gas loss during and after inflation. The possibility of yarn shifting, particularly where the yarns shift in and at many different ways and amounts, thus creates the quick deflation of the bag through quick escaping of inflation gasses. Thus, the base airbag fabrics do not provide much help in reducing permeability (and correlated leak-down times, particularly at relatively high pressures). It is this seam problem which has primarily created the need for the utilization of very thick, and thus expensive, coatings to provide necessarily low permeability in the past.
[0026] Recently, a move has been made away from both the multiple-piece side curtain airbags (which require great amounts of labor-intensive sewing to attached woven fabric blanks) and the traditionally produced one-piece woven cushions, to more specific one-piece woven fabrics which exhibit substantially reduced floats between woven yarns to substantially reduce the unbalanced shifting of yarns upon inflation, such as in Ser. Nos. 09/406,264 and 09/668,857, both to Sollars, Jr., the specifications of which are completely incorporated herein and described in greater depth hereafter:
[0027] The term “inflatable fabric” hereinafter is intended to encompass any fabric which is constructed of at least two layers of fabric which can be attached and/or sealed to form a bag article. The inventive inflatable fabric thus must include double layers of fabric to permit such inflation, as well as single layers of fabric either to act as a seal at the ends of such fabric panels, or to provide “pillowed” chambers within the target fabric upon inflation. The term “all-woven” as it pertains to the inventive fabric thus requires that the inflatable fabric having double and single layers of fabric be produced solely upon a loom. Any type of loom may be utilized for this purpose, such as water-jet, air-jet, rapier, and the like. Patterning may be performed utilizing Jacquard weaving and/or dobby weaving, particularly on fluid-jet and/or high speed rapier loom types.
[0028] The constructed fabric may exhibit balanced or unbalanced pick/end counts; the main requirement in the woven construction is that the single layer areas of the inflatable fabric exhibit solely basket-weave patterns. These patterns are made through the arrangement of at least one warp yarn (or weft yarn) configured around the same side of two adjacent weft yarns (or warp yarns ) within the weave pattern. The resultant pattern appears as a “basket” upon the arrangement of the same warp (or weft) yarn to the opposite side of the next adjacent weft (or warp) yarn. Such basket weave patterns may include the arrangement of a warp (or weft) yarn around the same side of any even number of weft (or warp) yarns, preferably up to about six at any one time, most preferably up to about 4.
[0029] The sole utilization of such basket weave patterns in the single layer zones provides a number of heretofore unexplored benefits within inflatable fabric structures. For example, such basket weave patterns permit a constant “seam” width and weave construction over an entire single layer area, even where the area is curved. As noted above, the standard Oxford weaves currently utilized cannot remain as the same weave pattern around curved seams; they become plain weave patterns. Also, such basket weave seam patterns permit the construction of an inflatable fabric having only plain woven double layer fabric areas and single layer “seams” with no “floats” of greater than three picks within the entire fabric structure. Such a fabric would thus not possess discrete locations where the air permeability is substantially greater than the remaining portions of the fabric. Additionally, such a weave structure permits the utilization of as low as two different weave densities (patterns, etc.) in the area of the produced seam. Thus, the seam itself is of one weave pattern and the weave pattern in the area directly adjacent to the seam is another weave pattern. No other patterns are utilized in that specific seam area. By directly adjacent, it is intended that such a described area is within at most 14 yarn-widths, preferably as low as 2 yarn-widths, and most preferably between about 4 and 8 yarn-widths, from the actual seam itself. Such a limitation on different weave densities has never been accomplished in all-woven airbags in the past.
[0030] Generally, the prior art (such as Thornton et al., supra) provides seam attachments exhibited at least three different weave densities within the directly adjacent area of the seams themselves. Furthermore, the prior art weaving procedures produce floats of sometimes as much as six or seven picks at a time. Although available software to the weaving industry permits “filling in” of such floats within weave diagrams, such a procedure takes time and still does not continuously provide a fabric exhibiting substantially balanced air permeability characteristics over the entire structure. The basket-weave formations within the single fabric layers thus must be positioned in the fabric so as to prevent irregularities (large numbers of floats, for example) in the weave construction at the interface between the single and double fabric layers (as described in FIG. 2, below). Another benefit such basket weave patterns accord the user is the ability to produce more than one area of single layer fabric (i.e., another “seam” within the fabric) adjacent to the first “seam.” Such a second seam provides a manner of dissipating the pressure from or transferring the load upon each individual yarn within both seams. Such a benefit thus reduces the chances of deleterious yarn shifting during an inflation event through the utilization of strictly a woven fabric construction (i.e., not necessarily relying upon the utilization of a coating as well). The previously disclosed or utilized inflatable fabrics having both double and single fabric layer areas have not explored such a possibility in utilizing two basket-weave pattern seams. Furthermore, such a two-seam construction eliminates the need for weaving a large single fabric layer area within the target inflatable fabric. The prior art fabrics which produce “pillowed” chambers for airbag cushions (such as side curtains), have been formed through the weaving of entire areas of single fabric layers (which are not actually seams themselves). Such a procedure is time-consuming and rather difficult to perform. The inventive inflatable fabric merely requires, within this alternative embodiment, at least two very narrow single fabric layer areas (seams) woven into the fabric structure (another preferred embodiment utilizes merely one seam of single layer fabric); the remainder of the fabric located within these two areas may be double layer if desired. Thus, the inventive fabric permits an improved, cost-effective, method of making a “pillowed” inflatable fabric.
[0031] The inflatable fabric itself, as noted above, is preferably produced from all-synthetic fibers, such as polyesters and polyamides, although natural fibers may also be utilized in certain circumstances. Preferably, the fabric is constructed of nylon-6,6, however, polyesters are also highly preferred. Mixtures of such fibers are also possible. The individual yarns utilized within the fabric substrate must generally possess deniers within the range of from about 40 to about 840; preferably from about 100 to about 630. Most preferably, such deniers average over the entire airbag fabric structure at most 525; more preferably average at most 420; and also preferably average 315 and even as low as 210, if desired. In such instances of such low average deniers (420 and below), the thickness of the fabric structure itself is quite low and thus, with the inventive coating applied at low add-on levels, exhibits excellent low packing volumes.
[0032] As noted above, coatings should be applied to the surface as a necessary supplement to reduce the air permeability of the inventive fabric. Since one preferred ultimate use of this inventive fabric is as a side curtain airbag which must maintain a very low degree of air permeability throughout a collision event (such as a rollover where the curtain must protect passengers for an appreciable amount of time), a decrease in permitted air permeability is highly desirable. With such a specific weaving pattern within the inventive inflatable fabric, lower amounts of coatings are permissible (as compared to other standard additions of such materials) to provide desired low inflation gas permeability. Any standard coating or laminate film, such as a silicone, polyurethane, polyamide, polyester, rubber (such as neoprene, for example), and the like, as discussed above, may be utilized for this purpose and may be applied in any standard method and in any standard amount on the fabric surface. However, the necessary amount of such a coating (or layers of coatings or laminate film or layer of laminate films) required to provide the desired low permeability is extremely low and is discussed in greater depth above. Again, the particular weave structures of the inventive inflatable fabric permits the utilization of such low coating amounts to provide the desired low permeability characterstics.
[0033] Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice for the invention. It is to be understood that both the foregoing general description and the following detailed description of preferred embodiments are exemplary and explanatory only, and are not to be viewed as in any way restricting the scope of the invention as set forth in the claims.
[0034] With such an improvement in one-piece side curtain airbags (and inflatable fabrics), the possibility of high leakage at seams is substantially reduced. These airbags provide balanced weave constructions at and around attachment points between two layers of fabrics such that the ability of the yarns to become displaced upon inflation at high pressures is reduced as compared with the standard one-piece woven airbags. Unfortunately, such inventive one-piece woven bags are still problematic in that the weave intersections may be displaced upon high pressure inflation such that leakage will still most likely occur at too high a rate for proper functioning. As a result, there is still a need to coat such one-piece woven structures with materials which reduce and/or eliminate such an effect. However, such one-piece woven structures permit extremely low add-on amounts of elastomeric coatings for low permeability effects. In fact, these inventive airbags function extremely well with low add-on coatings below 1.5 and as low as about 0.8 ounces per square yard.
[0035] Furthermore, although it is not preferred in this invention, it has been found that the inventive coating composition provides similar low permeability benefits to standard one-piece woven airbags, particularly with the inventive low add-on amounts of high tensile strength, high elongation, non-silicone coatings; however, the amount of coating required to permit high leak-down times is much higher than for the aforementioned Sollars, Jr. inventive one-piece woven structure. Thus, add-on amounts of as much as 1.5 and even up to about 2.2 ounces per square yard may be necessary to effectuate the proper low level of air permeability for these other one-piece woven airbags. Even with such higher add-on coatings, the inventive coatings themselves clearly provide a marked improvement over the standard, commercial, prior art silicone, etc., coatings (which must be present in amounts of at least 3.0 ounces per square yard).
[0036] Additionally, it has also been found that the inventive coating compositions, at the inventive add-on amounts, etc., provide the same types of benefits with the aforementioned sewn, stitched, etc., side curtain airbags. Although such structures are highly undesirable due to the high potential for leakage at these attachment seams, it has been found that the inventive coating provides a substantial reduction in permeability (to acceptable leak-down time levels, in fact) with correlative lower add-on amounts than with standard siliconeand neoprene rubber coating formulations. Such add-on amounts will approach the 3.0 ounces per square yard, but lower amounts have proven effective (1.5 ounces per square yard, for example) depending on the utilization of a sufficiently high tensile strength and sufficiently stretchable elastomeric component within the coating composition directly in contact with the target fabric surface. Again, with the ability to reduce the amount of coating materials (which are generally always quite expensive), while simultaneously providing a substantial reduction in permeability to the target airbag structure, as well as high resistance to humidity and extremely effective aging stability, the inventive coating composition, and the inventive coated airbag itself is clearly a vast improvement over the prior airbag coating art.
[0037] Of particular importance within this invention, is the ability to pack the coated airbag cushions within storage containers at the roof line of a target automobile in as small a volume as possible, such as within cylindrically or polygonally shaped modules. In a rolled, accordion-style, Z-folded (or any other) configuration (in order to best fit within the storage module itself, and thus in order to best inflate upon a collision event downward to accord the passengers sufficient protection), the inventive airbag may be constricted to a stored shape of as low volume as possible. It has been found that the best, though not the only, test of determining the effective low volume exhibited by a non-inflated side curtain airbag is to roll any bag lengthwise until it is substantially cylindrical in shape. In such a shape, it is preferable that the target side curtain airbag have a diameter of at most 23 millimeters. The term “diameter” is intended to encompass any cross-section of the inflatable fabric in its rolled storage configuration such that the length of the stored fabric is the same as the length of the inflated fabric, and measuring the greatest distance between opposite points on such a cross-sectional area. It should and would be well understood by one of ordinary skill in this particular art that the actual side curtain measured does not have to be stored in such a specific rolled manner in practice, only that, in order to assess the rolled packing volume in terms of diameter compared with depth, the target side curtain should be first laid flat and then rolled into a substantially cylindrical shape with the subsequent measurement of diameter then taken.
[0038] Thus, in one non-limiting example, a 2 meter long cylindrical roofline storage container, the necessary volume of such a container would equal about 830 cm 3 .(with the volume calculated as 2[Pi]radius 2 ) Standard rolled packing diameters are at least 25 millimeters for commercially available side curtain airbag cushions (due to the thickness of the required coating to provide low permeability characteristics). Thus, the required cylindrical container volume would be at least 980 cm 3 . Preferably, the rolled diameter of the inventive airbag cushion during storage is at most 20 millimeters (giving a packed volume of about 628 cm 3 ) (and up to 23 millimeters and as low as possible, for example, about 16 millimeters) which is clearly well below the standard packing volume. Of course, the ability to provide very low packing volumes in directly related to the thickness of coating applied to the airbag itself, as well as, possibly, the denier fibers utilized to produce the bag itself. The lower the denier, the thinner the bag construction, and thus, the potential for lower packing volumes. In relation, then, to the depth of the airbag cushion upon inflation (i.e., the length the airbag extends from the roofline down to its lowest point along the side of the target automobile, such as at the windows), a packing volume equal to the quotient of the particular bag's packed diameter (again in its rolled state although any other packing configuration, such as “accordion-style,” “Z-fold”, and the like, may be utilized as well as rolling in actual practice) divided by inventive airbag cushion's depth (which is often, though not required to be measured, at approximately 17 inches or 431.8 millimeters) should be at most 0.05. Preferably this factor should be at most 0.486 (21 millimeter diameter), more preferably at most about 0.0463 (20 millimeters) or 0.044 (19 mm), or 0.0417 (18 mm), or 0.0394 (17 millimeters). Most preferably, the denier fibers utilized are about 420 on average and thus with a coating add-on amount of about 0.8 ounces/square yard provides a packing diameter of about 18 millimeters (and thus a packing volume factor of about 0.0417).
[0039] The prior art, having extremely thick coatings with relatively high denier fibers (420 and higher) provides, at best, a packing diameter of about 24 millimeters which thus provides (with a coating in excess of 4.0 ounces per square yard, generally) a packing volume factor of about 0.0556, well above the 0.05 limit taught above. As discussed above, with lower average denier fibers utilized within the subject side curtain airbag, the packing volume may be reduced. Such as within the scope of this invention as the primary, though not only, aim of reducing such packing volume is to provide an highly effective (i.e., very low permeability), low add-on coating to the target side curtain airbag. Of course, the aforementioned range of factors does not require the airbag depth to be at a standard of 17 inches, and is primarily a function of coating thickness, and thus add-on weight, as well as yarn denier. As should be evident, however, longer (deeper) bags would require greater diameters in packing within a cylindrical storage capsule.
[0040] Surprisingly, it has been discovered that any elastomer with a tensile strength of at least 2,000 psi and an elongation at break of at least 180% coated onto and over both sides of a side curtain airbag fabric surface at a weight of at most 3.0 ounces per square yard, and preferably between 0.8 and 2.0, more preferably from 0.8 to about 1.5, still more preferably from 0.8 to about 1.2, and most preferably about 0.8 ounces per square yard, provides a coated airbag cushion which passes both the long-term blocking test and long-term oven aging test with very low, and extended permeability upon and after inflation. This unexpectedly beneficial type and amount of coating thus provides an airbag cushion which will easily inflate after prolonged storage and will remain inflated for a sufficient amount of time to ensure an optimum level of safety within a restraint system. Furthermore, it goes without saying that the less coating composition required, the less expensive the final product. Additionally, the less coating composition required will translate into a decrease in the packaging volume of the airbag fabric within an airbag device. This benefit thus improves the packability for the airbag fabric.
[0041] While the invention will be described and disclosed in connection with certain preferred embodiments and practices, it is in no way intended to limit the invention to those specific embodiments, rather it is intended to cover equivalent structures structural equivalents and all alternative embodiments and modifications as may be defined by the scope of the appended claims and equivalence thereto.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0042] Two potentially preferred elastomer compositions of this invention was preferably produced in accordance with the following Tables:
TABLE 1 Standard Water-Borne Elastomer Composition Component Parts (per entire composition) Resin (30-40% solids content in water) 100 Natrosol ® 250 HHXR (thickener) 10 Irganox ® 1010 (stabilizer) 0.5 DE-83 R (flame retardant) 10
[0043] [0043] TABLE 2 Standard Solvent-Borne Elastomer Composition Component Parts (per entire composition) Resin (30-40% solids content in solvent) 100 Irganox ® 1010 (stabilizer) 0.5 DE-83 R (flame retardant) 10
[0044] [0044] TABLE 3 Standard Solvent-Borne Elastomer Composition Component Parts (per entire composition) Resin (25-40% solids content in solvent) 100 Irganox ® 1010 (stabilizer) 0.5 DE-83 R (flame retardant) 10 Desmodur CB-75 (adhesion promoter) 2
[0045] (The particular resins are listed below in Table 4 and thus are merely added within this standard composition in the amount listed to form preferred embodiments of the inventive coating formulation).
[0046] The compounded compositions exhibited viscosities measured to be about 15,000 centipoise by a Brookfield viscometer. Once compounding was complete, the individual formulations were applied to separate articles being both sides of one-piece Jacquard woven airbags (having 420 denier nylon 6,6 yarns therein) as discussed within the Sollars, Jr. application noted above. Such applications were performed through a fixed gap coating procedure. The bag was then dried at an elevated temperature (about 300° F. for about 3 minutes) and thus form to form the necessarily thin coatings. As noted above, scrape coating may also be followed to provide the desired film coating; however, fixed gap coating provides the desired film thickness uniformity on the bag surface and thus is preferred. Scrape coating, in this sense, includes, and is not limited to, knife coating, in particular knife-over-gap table, floating knife, and knife-over-foam pad methods. The final dry weight of the coating is preferably from about 0.6-3.0 ounces per square yard or less and most preferably 0.8-1.5 ounces per square yard or less. The resultant airbag cushion is substantially impermeable to air when measured according to ASTM Test D737, “Air Permeability of Textile Fabrics,” standards.
[0047] In order to further describe the present invention the following non-limiting examples are set forth. These examples are provided for the sole purpose of illustrating some preferred embodiments of the invention and are not to be construed as limiting the scope of the invention in any manner. These examples involve the incorporation of the below-noted preferred elastomers within the coating formulations of TABLES 1-3, above.
[0048] Each coated bag was first subjected to quick inflation to a peak pressure of 30 Psi. Air leakage (SCFH) of the inflated bag was then measured at 10 Psi pressure. The characteristic leak-down time t(sec) was calculated based on the leakage rate and bag volume.
TABLE 4 Tensile Elonga- T (sec). T (sec.) Coating add- Example Number/ Strength tion at Before Post- on weight Elastomer (Psi) break (%) aging aging* (oz/yd2) 1. Impranil ® 85 6000 400 18.1 16.3 0.8 UD 2. Ex 51-550 3100 320 110.2 105 0.8 3. Impranil ® 7200 300 120.2 125 0.9 ELH 4. Ru ® 41-710 7000 600 27.3 26.4 0.8 5. Ru ® 40-350 7000 500 34.4 36.2 0.8 6. Bayhydrol ® 6000 300 8.6 5.7 0.8 123 7. Dow Corning 700 90 <2 <2 2.1 3625** 8. Silastic 94- 1400 580 <2 <2 1.8 595-HC** 9. Ru ® 40-415 5000 180 <2 <2 0.8 10. Sancure ® 3000 580 25.2 <2 0.8 861 11. Witcobond ® 6000 600 28.4 <2 0.8 290H
[0049] As noted above, Examples 1-6 work extremely well and are thus within the scope of this invention. Examples 10 and 11 show some limitations, polyester based elastomers (Witcobond® 290H) exhibit excellent heat aging (oxidation) stability but tend to hydrolyze easily at high humidity; polyether based elastomers (Sancure® 861) have excellent hydrolysis resistance, but poor oxidation performance. However, these elastomers have proven to be acceptable permeability reducers at higher add-on weights below the maximum of 3.0 ounces per square yard. Furthermore, although silicones show excellent resistance to heat aging and hydrolysis (humidity aging), they, however, possess limited tensile strength and tear resistance resistance. Natural rubber, SBR, chloroprene rubbers and others containing unsaturated carbon double bonds have excellent hydrolysis resistance. But the unsaturated carbon double bond that gives their elasticity oxidizes readily and the properties of the rubber change after heat aging. Elastomers that have good physical properties and excellent resistance to hydrolysis and oxidation are preferred for this application. Polyurethanes based on polycarbonate soft segments are the preferred materials for this application.
[0050] The airbag of Example 3 exhibited a sliding coefficient of friction constant of roughly 0.6. A comparative thick silicone-coated side curtain airbag which included a non-woven layer, exhibited a constant of about 0.8.
BRIEF DESCRIPTION OF THE DRAWINGS
[0051] [0051]FIG. 1 is a cross-sectional view of an inventive all-woven inflatable fabric showing the preferred double and single layer areas including two separate single layer areas.
[0052] [0052]FIG. 2 is a weave diagram illustrating a potentially preferred repeating pick pattern formed using repeating plain weave and basket weave four-pick arrangements.
[0053] [0053]FIG. 3 depicts the side, inside view of a vehicle prior to deployment of the inventive side curtain airbag.
[0054] [0054]FIG. 4 depicts the side, inside view of a vehicle after deployment of the inventive side curtain airbag.
[0055] [0055]FIG. 5 depicts a side view of a side curtain airbag.
[0056] [0056]FIG. 6 provides a side view of a side curtain airbag container.
[0057] [0057]FIG. 7 provides a cross-sectional perspective of the stored airbag within the container of FIG. 6.
DETAILED DESCRIPTION OF THE DRAWINGS
[0058] Turning now to the drawings, in FIG. 1 there is shown a cross-section of a preferred structure for the double fabric layers 12 , 14 , 18 , 20 , 24 , 26 and single fabric layers 16 , 22 of the inventive inflatable fabric 10 . Weft yarns 28 (exhibiting preferably deniers of about 420 each) are present in each of these fabric layer areas 12 , 14 , 16 , 18 , 20 , 22 , 24 , 26 over and under which individual warp yarns 38 , 40 , 42 , 44 (also exhibiting deniers preferably of about 420) have been woven. The double fabric layers 12 , 14 , 18 , 20 , 24 , 26 are woven in plain weave patterns. The single fabric layers 16 , 22 are woven in basket weave patterns. Four weft yarns each are configured through each repeating basket weave pattern within this preferred structure; however, anywhere from two to twelve weft yarns may be utilized within these single fabric layer areas (seams) 16 , 22 . The intermediate double fabric layer areas 18 , 20 comprise each only four weft yarns 28 within plain weave patterns. The number of such intermediate weft yarns 28 between the single fabric layer areas 16 , 22 must be in multiples of two to provide the maximum pressure bearing benefits within the two seams 16 , 22 and thus the lowest possibility of yarn shifting during inflation at the interfaces of the seams 16 , 22 with the double fabric layer areas 12 , 14 , 24 , 26 .
[0059] [0059]FIG. 2 shows the weave diagram 30 for an inventive fabric which comprises two irregularly shapes concentric circles as the seams. Such a diagram also provides a general explanation as to the necessary selection criteria of placement of basket-weave patterns within the fabric itself. Three different types of patterns are noted on the diagram by different shades. The first 32 indicates the repeated plain weave pattern throughout the double fabric layers ( 12 , 14 , 18 , 20 , 24 , 26 of FIG. 1, for example) which must always initiate at a location in the warp direction of 4X +1, with X representing the number of pick arrangement within the diagram, and at a location in the fill direction of 4X+1 (thus, the pick arrangement including the specific two-layer plain-weave-signifying-block 32 begins at the block four spaces below it in both directions). The second 34 indicates an “up-down” basket weave pattern wherein an empty block must exist and always initiate the basket-weave pattern at a location in the warp direction of 4X+1, with X representing the number of repeating pick arrangements within the diagram, and at a location in the fill direction of 4X+1, when a seam (such as 16 and 22 in FIG. 1) is desired (thus, the pattern including the pertinent signifying “up-down” block 34 includes an empty block within the basket-weave pick arrangement in both the warp and fill directions four spaces below it). The remaining pattern, which is basically a “down-up” basket weave pattern to a single fabric layer (such as 16 and 22 in FIG. 1) is indicated by a specifically shaded block 36 . Such a pattern must always initiate at a location in the warp direction of 4X+1 and fill of 4X+3, or warp of 4X+3 and fill of 4X+1, when a seam is desired. Such a specific arrangement of differing “up-down” basket weave 34 and “down-up” basket weave 36 pattern is necessary to effectuate the continuous and repeated weave construction wherein no more than three floats (i.e., empty blocks) are present simultaneously within the target fabric structure. Furthermore, again, it is believed that there has been no such disclosure or exploration of such a concept within the inflatable fabric art.
[0060] As depicted in FIG. 3, an interior of a vehicle 110 prior to inflation of a side curtain airbag (not illustrated) is shown. The vehicle 110 includes a front seat 112 and a back seat 114 , a front side window 116 and a back-side window 118 , a roofline 120 , within which is stored a cylindrically shaped container 122 comprising the inventive side curtain airbag (not illustrated). Also present within the roofline 120 is an inflator assembly 124 which ignites and forces gas into the side curtain airbag ( 126 of FIG. 4) upon a collision event.
[0061] [0061]FIG. 4 shows the inflated side curtain airbag 126 . As noted above, the airbag 126 is coated with at most 2.5 ounces per square of a coating formulation (not illustrated), preferably polyurethane polycarbonate. The inventive airbag 126 will remain sufficiently inflated for at least 5 seconds, and preferably more, as high as at least 20 seconds, most preferably.
[0062] [0062]FIG. 5 shows the side curtain airbag 126 prior to storage in its uninflated state within the roofline cylindrically shaped container 122 . The thickness of the airbag 126 , measured as the packing diameter (as in FIG. 7, below) as compared with the depth of the airbag measured from the roofline cylindrically shaped container 122 to the bottom most point 128 of the airbag 126 either in its uninflated or inflated state at most 0.05. Larger factors are possible with higher add-on coating weights and larger yarns. Smaller yarns may be utilized with lower or larger add-on coating weights as well which meet this limitation as well.
[0063] [0063]FIGS. 6 and 7 aid in understanding this concept through the viewing of the rolled airbag 126 as stored within the container 122 along line 2 . The diameter measurement of the airbag 126 of Example 3, above, is roughly 20 millimeters. The standard depth of side curtain airbags is roughly 17 inches, or about 431.8 millimeters. Thus, the preferred packing volume factor is about 0.046 (20 mm/431.8 mm). A comparative silicone-based thick coating add-on weight of about 4.0 ounces per square yard provided a diameter of about 25 millimeters for a factor of about 0.0579 (25 mm/431.8 mm).
[0064] There are, of course, many alternative embodiments and modifications of the present invention which are intended to be included within the spirit and scope of the following claims. In particular, it is to be understood that any side curtain airbag of any production method and structure which exhibits low permeability measurements with very low coating add-on amounts, and specifically meets the packing volume (be it as a rolled fabric, or packed accordion-style, or other packed configuration) limitations noted above is within the scope of this invention. | Coated inflatable fabrics, more particularly airbags to which very low add-on amounts of coating have been applied, are provided which exhibit extremely low air permeabilities. The inventive fabrics are primarily for use in automotive restraint cushions which require low permeability characteristics (such as side curtain airbags). Traditionally, heavy, and thus expensive, coatings of compounds such as neoprene, silicones and the like, have been utilized to provide such required low permeability. The inventive fabric utilizes an inexpensive, very thin coating to provide such necessary low permeability levels. Thus, the inventive coated airbag possesses a coating of at most 3.0 ounces per square yard, most preferably about 0.8 ounces per square yard, and exhibits a leak-down time (a measurement of the time required for the entire amount of gas introduced within the airbag at peak pressure during inflation to escape the airbag at 10 psi) of at least 5 seconds as well as very low packing volumes (for more efficient use of storage space within a vehicle). All coatings, in particular elastomeric, preferably, though not necessarily, non-silicon coatings, and coated airbags meeting these criteria are intended to reside within the scope of this invention. | 3 |
FIELD OF THE INVENTION
The invention relates to a method for separating woody material from plant fibers and, more particularly, to a method for decorticating shive from flax straw to yield flax fibers by subjecting the flax straw to processing sections, each having sets of fluted rollers which are rotated at different rotation rates from adjacent sets of rollers to bend and pull the shive and thereby strip shive from the flax fibers.
BACKGROUND OF THE INVENTION
Various methods of decorticating flax straw, that is, separating the woody shive material from the flax plant fibers, have been proposed. Apart from retting and chemical treatment processes, most systems for mechanically working flax straw rely on some sort of scutching or a beating or flailing action as the primary mechanism to break up the woody material and dislodge the same from associated fibers. Examples of machines utilizing scutching or beating action in removing shive are disclosed in U.S. Pat. Nos. 2,418,694 and 2,741,894.
The problem with beating flax straw to break loose the shive material is that the beating action can also damage or break the fibers and thereby shorten the fibers separated from the shive. In many applications for these fibers, long fibers can be necessary for strength purposes such as in papermaking, preparation of fiberboard-types of materials, production of textiles, and reinforcing other fibers, plastic or composite material, and thus the shorter fibers produced by prior methods of decortication are undesirable. In addition to longer fibers, it is also economically desirable to be able to process high rates of flax straw through decorticating machines with relatively low power requirements.
SUMMARY OF THE INVENTION
According to the invention, a method for separating woody material from plant fibers is disclosed which includes the provision of a plurality of woody material bending regions with the plant material being fed to a first and then a second one of the bending regions as bending and pulling surfaces are moved through the bending regions. The bending and pulling surfaces move through the regions at different operating speeds so that the bending and pulling surfaces in adjacent bending regions will pull on the plant material to separate the fibers from the woody material. As the bending and pulling surfaces primarily impart a pulling or stripping force on the fiber along its length where the fiber has its most strength, the woody material can be dislodged and stripped away lengthwise with minimal damage or breakage of the fiber. In addition, if the friction of being pulled over the bending and pulling surfaces becomes too large at the removal point of the woody material, the woody material will overcome the pulling force and the plant material will not be pulled and will cease its relative motion and move between the bending and pulling surfaces in a region until it is once again to a point where it can be pulled and removal of woody material can be accomplished. In this manner, damage such as by breaking of the plant fiber is limited.
The step of providing bending regions may include the step of providing first and second sets of fluted rollers having bending and pulling radially extending flute surfaces. The plant material is fed to the first bending region between the first set of fluted rollers and then the second bending region between the second set of fluted rollers. The method utilizing fluted rollers allows very high flow rates of plant material to be processed with relatively low power requirements compared to processes which primarily rely on mechanically working and beating or flailing of the plant material to break loose the woody material.
The step of separating fibers from woody material may include the step of causing the plant to undergo back and forth bending and pulling as the bending and pulling flute surfaces engage the plant material as they move through their respective bending regions to crimp and break woody material and to strip the woody material from the plant fibers. By back and forth bending of the woody material, areas of weakness are created which when subjected to pulling forces will allow the woody material to be stripped from the plant fibers.
The method may further include the steps of feeding plant material to a third one of the bending regions after it is moved through the second bending region and causing the third region bending and pulling surfaces to move through the third region at an operating speed different than the operating speed of the first and second region bending and pulling surfaces. Preferably, the bending and pulling surfaces are caused to move through the first, second and third bending regions at progressively increasing operating speeds. In this manner, the plant material will be pulled between the bending regions such as by the second region bending and pulling surfaces from the first region and by the third region bending and pulling surfaces from the second region to strip the woody material from the plant fibers.
Preferably, the first, second and third bending regions are provided together as a first plant material processing section with additional processing sections being provided for feeding plant material successively to each of the processing sections. The plant material can be fed to five processing sections at a rate of at least 10,000 pounds per hour and yielding as fiber output from the final processing section in the range of 55-60% of fiber purity. Thus, the method of the present invention has increased processing rates while still yielding relatively high percentages of fiber as output over prior decorticating methods.
Another aspect of the invention is a method for decorticating shive from flax straw to yield flax fibers, including the steps of providing sets of upper and lower fluted rollers, with the upper and lower rollers arranged in a set to provide an area therebetween where the flutes of the upper rollers overlap with the flutes of the lower rollers as the rollers are rotated, rotating sets of fluted rollers at different predetermined rotation rates, feeding flax straw to the flute overlap areas between the upper and lower rollers, bending the shive of the flax in the fluted overlap areas by engagement with the roller flutes while limiting damage to the flax fibers, and pulling bent shive from one set of rollers to the next as a result of the different rotation rates of the roller sets to strip the shive from the flax and produce flax fibers.
Preferably, the step of providing sets of fluted rollers includes providing a first set of feed rollers, a second set of intermediate feed rollers and a third set of high speed rollers with the flax being fed successively from the first set to the second set to the third set of rollers. The rotating step may include rotating the feed rollers at a rate of approximately 60-110 revolutions per minute (rpm), the intermediate speed rollers at a rate of approximately 1000-1750 rpm, and the high speed rollers at a rate of approximately 2000-3500 rpm.
The method may include the step of providing a set of upper and lower crush rollers, feeding the flax to the crush rollers, producing a thin mat of compressed flax, and feeding the thin flax mat to the first set of rollers.
The method may include the steps of providing removable flutes on the fluted rollers and removing worn flutes on the rollers and replacing the removed flutes with new flutes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a machine which can be used to carry out the method of the present invention and shows a machine frame for supporting sets of fluted roller assemblies through which plant material travels;
FIG. 2 is a side elevational view of the machine of FIG. 1 including an optional scutching unit provided at the outlet end of the machine;
FIG. 3 is an enlarged fragmentary view of optional crush feed rollers and the first processing section of FIG. 2;
FIG. 4 is a block diagram of the method according to the present invention where the plant material is first fed to a crushing area and then to a plurality of processing sections each having varying speed sets of rollers and then to the scutching area;
FIG. 5A is a front elevational view of one of the roller assemblies and a removable flute before it is mounted to the roller;
FIG. 5B is a view similar to FIG. 5A with the flute attached to the roller;
FIG. 6 is a front elevational view of the drive system for one of the sets of feed rollers; and
FIG. 7 is a front elevational view of the drive system for one of the sets of intermediate or high speed rollers.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A machine 10 is depicted in FIG. 1 which can carry out the method of separating woody material from plant fibers in accordance with the present invention. The machine 10 includes a framework 12 for supporting sets of roller assemblies 14 and their associated drives 16.
Referring to FIGS. 2-4, the method in accordance with the invention includes arranging the roller assemblies 14 in sets so that they define the woody material bending regions 18 between upper and lower rollers 14a and 14b in a set. The plant material 20 is then fed through these bending regions 18, as best seen in FIG. 3. The method herein utilizing the machine 10 is ideally suited for decorticating flax straw to yield flax fibers, although it will be recognized that other plant material from which it is desired to separate woody material from the plant fibers can also be processed by way of the method of the present invention.
To separate the woody material from the plant fibers, the roller assemblies 14 are provided with bending or pulling surfaces or flutes 22 thereon. The rollers 14 in a set are arranged so that the bending and pulling surfaces 22 move through the bending regions 18 in an overlapping manner, thereby bending the plant material 20 in the bending region 18. The bending and pulling surfaces 22 are caused to move through their respective bending regions 18 at different predetermined operating speeds so that the plant material 20 is pulled from the slower moving sets of roller assemblies 14 to the faster moving roller sets. In this fashion, the woody material on the exterior of the plant material 20 is bent creating areas of weakness with the woody material then being gripped by the surfaces 22 and pulled from one set of rollers 14 to the next to strip the woody material off of the fibers leaving a relatively long length of unbroken fibers as the final product. This is a significant improvement over prior methods which mechanically work the straw, such as by beating and flailing the straw to break loose the shive material as in those processes the fiber length was typically much shorter than that produced by way of the present method. In addition, the present method does not require any pretreatment of the flax straw such as by field retting and has been found to work well with straw in a wide variety of conditions.
More particularly, the sets of roller assemblies 14 include a set of low speed, smaller diameter feed rollers 24, intermediate speed, larger diameter rollers 26 and high speed large diameter rollers 28 which make up a single processing section of the machine 10. Preferably, the intermediate speed rollers 26 and the high speed rollers 28 are of substantially equal diameters. As can be seen in FIG. 2, five such processing sections are provided in the machine 10.
As the flax straw material 20 is fed from one processing section to the next, shive is progressively removed from the fiber by the bending and stripping action, as previously described. The woody shive falls out of the machine 10 between the processing sections and is conveyed away with the fiber being carried forward to the end of the machine 10 and out from the last processing section. With the decorticating method herein, the percentage of fiber obtained from flax straw has been found to be in the range of 55 to 60 percent fiber purity. To obtain even higher percentages of fiber, the fiber material from the machine 10 can then be fed to a scutching unit 30 which gently mechanically works the fibers to dislodge remaining portions of shive left on the fibers without damage to the fibers. Utilizing the scutching unit can increase fiber purity up to around 80 percent. Field retting of the straw and exercising control over the straw moisture content can also assist in increasing fiber purity. Adjustment of the roller spacing and speed of the machine 10 can also help in obtaining higher purity percentages.
For determining fiber purity, a twenty (20) gram sample can be taken from the processed fiber. The sample can then be ground in 2 mm lengths in a Willey Grinding Mill. The ground sample is weighed and placed in a mini-cyclone separator. A vacuum cleaner is used to provide air flow for separating shive and fiber and as the sample is mixed, fiber is separated by way of air classification. As the shive particles are heavier, they remain in the mixer with the fiber being carried by the air flow and removed from the flow by a mini-cyclone and routed to a different sample container. After removal of fiber from the shive, the remaining shive is weighed and a purity percentage of fiber is calculated using the weight of the measured weight of the shive and the sample weight.
As previously mentioned, it is preferred that the feed rollers 24 are operated at a predetermined operating speed that is lower than the predetermined operating speed for the intermediate speed rollers 26 which, in turn, is lower than the predetermined operating speed for the high speed rollers 28. In this manner, flax 20 is pulled from between the bending region 18a between the feed rollers 24a and 24b to the bending region 18b between the intermediate speed rollers 26a and 26b. Similarly, the flax 20 is pulled from the bending region 18b between the intermediate speed rollers 26a and 26b to the bending region 18c between the high speed rollers 28a and 28b. Preferably, the feed rollers are rotated at a rate of approximately 60-110 rpm, the intermediate speed rollers 26 at a rate of approximately 1000-1750 rpm, and the high speed rollers at a rate of approximately 2000-3500 rpm to achieve the pulling and stripping action between sets of roller assemblies 14.
Thus, it is apparent that flax material 20 introduced to the roller assemblies 14 will be bent in a back and forth fashion in the bending regions 18 over and between the surfaces of the flutes 22 of roller assemblies 14 which will produce areas of weakness in the exterior woody shive material of the flax 20. Then, as the flax 20 is caused to be pulled between sets of rollers 14, the woody shive material will tend to dislodge from the fiber at the areas of weakness thus stripping the shive from the flax fibers. In addition, as the flax 20 will tend to be reoriented as it is fed between the roller assemblies 14 through the bending regions 18 to travel in a transverse direction across the flutes 22, in other words, so that the flax straw 20 is arranged lengthwise in a direction normal to the axes of the roller assemblies 14, the pulling force between sets of roller assemblies 14 will act on the fibers along their length where the fiber has its most strength, thus limiting any damage or breaking of the fibers tending to shorten the fiber length. Moreover, the fibers are sufficiently flexible so as to bend around the flutes 22 without tearing such as can occur when they are subjected to a beating or flailing action or impacted with a sharp edge as in many prior decorticating methods.
As described earlier, the flax straw 20 will tend to orient itself so that it travels along its length in a direction substantially normal to the axis of the roller assemblies 14. In some applications, it may be desirable to provide a set of crush rollers 32 before the processing sections to form a flax straw mat and to provide protection against foreign objects. The crush rollers 32 are driven by a crush roller drive 33 and can be spring loaded together to define a mat forming nip area 34 therebetween so that when flax straw 20 is introduced to the nip area 34, a thin straw mat will be produced and the shive material will be compressed to make it more brittle and prone to breakage as it is fed through the bending regions 18. The machine 10 utilizing elongate roller assemblies 14 can handle increased processing rates of flax straw 20, e.g., 10,000 lbs./hr., versus other methods used by prior decorticating machines. After the flax material 20 has been fed through the processing sections and scutching unit 30, the fiber is collected and can be shaken to remove any loose shive whereupon it is then ready for baling.
Turning to FIGS. 5A and 5B, the preferred construction of the roller assemblies 14 will now be described. While the preferred assembly of the flutes 22 is described herein, it will be manifest that many other means for forming the roller assemblies 14, including their flutes 22 could be utilized. The roller assemblies 14 can each have a shaft 36 having an enlarged diameter cylindrical mounting portion 38 with smaller diameter stub shaft portions 40 and 42 extending from either end 38a and 38b thereof. On the cylindrical mounting portion 38, a number of short cylindrical spacer members 44 are mounted as by welding. The spacer members 44 are each provided with notches or slots 46 formed in one end face at their outer periphery. In addition, a pair of annular discs 48 and 50 are mounted between the innermost spacer members 44a and 44b on the cylindrical mounting portion 38 approximately mid-way between either end 38a and 38b thereof. The annular disc 48 includes locating slots 51 which extend from the outermost periphery radially inwardly towards the center. The disc 50 includes capturing apertures (not shown) which are spaced around the annular body of the disc 50 and in alignment with the slots 51 of disc 48.
The flutes 22 each include an elongate portion 52 which extends substantially along the entire length of the large diameter mounting portion 38. Depending from the bottom edge of the elongate portion 52 are a plurality of flange hooks 54 which fit into the peripheral slots 46 of the spacer members 44. To fix the circumferential position of the flutes 22, the central flange hook 54a is provided with a lowered tab 56 which can be slid into one of the apertures in annular disk 50, as seen in FIG. 5B. Similarly, the end flanges 54b and 54c can be provided with respective tabs 58 and 60 for mounting in apertures (not shown) of end locking caps 62 and 64, respectively. In one form, the end caps 62 and 64 are welded to the ends 38a and 38b of the cylindrical mounting portion 38. In another form, the end caps 62 and 64 are press fit or threaded on the ends 38a and 38b. In this manner, the flutes 22 can be removably secured onto the spacer members 44 providing roller assemblies 14 with a plurality of circumferentially spaced flutes 22 which can be removed once worn and replaced with new flutes 22.
As previously mentioned, the roller assemblies 14 include respective drives 16. As shown in FIG. 1, the drives 16 are mounted on drive mounting platforms 66 and 68 of the framework 12 on either side of the roller assemblies 14. More specifically and referring to FIG. 6, a feed roller assembly drive system 70 is shown including a motor 72 mounted atop a speed or gear reducer housing 74. A drive shaft 76 extends from the housing 74 into gearing housing 78 in which gearing (not shown) is provided for transmitting the rotary power from the drive shaft 76 to opposite or counter rotary motion of a counter shaft 80 to be imparted to upper feed roller 24a.
The framework 12 includes upper and lower mounting beams 82 and 84 extending lengthwise on either side of the sets of roller assemblies 14. The ends 38a of the cylindrical mounting portions 38 of the shafts 36 are mounted in bearing housings with upper bearing housing 86 attached to the upper beam 82 and lower bearing housing 88 attached to the lower beam 84.
To drive the upper and lower feed rollers 24a and 24b with opposite rotary motion and at the same speed so as to move their respective flutes 22 through the bending region 18 defined in the overlap area of the flutes 22 and thereby bend and pull on the flax straw 20 fed therethrough, the drive shaft 76 and counter shaft 80 are coupled to respective intermediate shafts 90 and 92 which, in turn, are coupled to the stub shafts 40 of the lower feed roller 24b and the upper feed roller 24a, respectively. Due to the relatively small diameters of the feed rollers 24 and the larger displacement between the drive shaft 76 and counter shaft 78, the counter shaft 80 is offset from the axis of the upper roller 24a which it drives. In other words, the counter shaft 80 is displaced vertically higher from the axis of the upper roller 24a, and therefore, the intermediate shaft 92 is inclined downwardly from the counter shaft 80 to the stub shaft 40 of the upper roller 24a. Since it is important that the rollers 24a and 24b rotate with equal speeds in opposite directions, the intermediate shaft 92 is coupled at respective ends 92a and 92b thereof to the counter shaft 80 and the stub shaft 40 of the upper roller 24a by way of flexible couplings that are CV or constant velocity joints 94 and 96, respectively, as are known. On the other hand, the drive shaft 76 is aligned and coaxial with the shaft of the lower feed roller 24b so that more rigid couplings 98 and 100 can be used between the drive shaft 76 and one end 90a of the intermediate shaft 90 and the other end 90b of the intermediate shaft 90 and the stub shaft 40 of the lower roller 24b.
The drive system 102 for the intermediate and high speed rollers 26 and 28 are mounted on the frame platform 68 on the opposite side of the roller assemblies 14. Motors 104 for the intermediate and high speed rollers 26 and 28 are substantially the same and the motors 104 for the intermediate speed rollers 26 are arranged in staggered relation from the motors 104 for the high speed rollers 28 on the frame platform 68. Otherwise, the remainder of the drive system 102 is substantially identical for either the intermediate speed rollers 26 or high speed rollers 28 so that only the drive system for the intermediate speed rollers 26 will be described herein.
Referring to FIG. 7, the motor 104 is arranged horizontally on the platform 68 with its drive shaft 106 coupled to secondary shaft 108 by way of shaft coupling 110. The secondary drive shaft 108 drives gears (not shown) in gear housing 112 to transmit the rotary power from the drive shaft 106 to counter rotary motion of counter shaft 114 which is imparted to upper intermediate rollers 26a.
Similar to the ends 38a of the mounting portion 38 of the shafts 36 on the side of the feed roller drive system 70 which are supported in bearing housings 86 and 88, the other ends 38b of the mounting portion 38 of the shaft 36 on the side of the intermediate and high speed drive systems 102 are supported in upper and lower bearing housings 116 and 118, respectively.
The following is a description of the drive system 102 and shafting for the intermediate speed rollers 26 (which is substantially the same as that of the high speed rollers 28), with the differences from the feed roller drive system 70 and shafting being due to the difference in diameters between the feed rollers 24 and the intermediate and high speed rollers 26 and 28 and the speeds at which they are driven. To drive the upper and lower intermediate speed rollers 26a and 26b with opposite rotary motion and at the same speed so as to move their respective flutes 22 through the bending regions 18b defined in the overlap areas of the flutes 22 and thereby bend and pull on the flax straw 20 fed therethrough, the secondary drive shaft 108 and counter shaft 114 are coupled to respective intermediate shafts 120 and 122 which, in turn, are coupled to the stub shafts 40 of the lower intermediate speed rollers 26b and the upper intermediate speed rollers 26a, respectively. Due to the larger diameters of the intermediate speed rollers 26 and the smaller displacement between the secondary shaft 108 and counter shaft 114, the counter shaft 114 is offset from the axis of the upper rollers 26a which it drives. In other words, the counter shaft 114 is displaced vertically lower from the axis of the upper roller 26a, and therefore, the intermediate shaft 122 is inclined upwardly from the counter shaft 114 to the stub shaft 40 of the upper roller 26a. Since it is important that the rollers 26a and 26b rotate with equal speed in opposite directions, the intermediate shaft 122 is coupled at respective ends 122a and 122b thereof to the counter shaft 114 and the stub shaft 40 of the upper rollers 26a by way of flexible couplings that are CV or constant velocity joints 124 and 126, as are known. On the other hand, the secondary shaft 108 is aligned and coaxial with the shaft of the lower intermediate speed roller 26b and high speed roller 28b so that more rigid couplings 128 and 130 can be used between the secondary shaft 108 and one end 120a of the intermediate shaft 120 and the other end 120b of the intermediate shaft 120 and the stub shaft 40 of the lower rollers 26b and 28b.
While there have been illustrated and described particular embodiments of the present invention, it will be appreciated that numerous changes and modifications will occur to those skilled in the art, and it is intended in the appended claims to cover all those changes and modifications which fall within the true spirit and scope of the present invention. | A method for separating woody material from plant fibers is disclosed which includes the provision of a plurality of woody material bending regions with the plant material being fed to a first and then a second one of the bending regions as bending and pulling surfaces are moved through the bending regions. The bending and pulling surfaces move through the regions at different operating speeds so that the bending and pulling surfaces in adjacent bending regions will pull on the plant material to separate the fibers from the woody material. As the bending and pulling surfaces primarily impart a pulling or stripping force on the fiber along its length where the fiber has its most strength, the woody material can be dislodged and stripped away lengthwise with minimal damage or breakage of the fiber. The step of providing bending regions can include the step of providing first and second sets of fluted rollers having bending and pulling radially extending flute surfaces. The plant material is fed to the first bending region between the first set of fluted rollers and then the second bending region between the second set of fluted rollers. Preferably, a third bending region is also provided and the bending and pulling flutes are caused to move through the first, second and third regions at progressively increasing operating speeds. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of co-pending U.S. Ser. No. 12/182,377, filed Jul. 30, 2008, entitled “System and Program Product of Doing Pack Unicode ZSeries Instructions,” by Rajendran et al., which is a continuation of U.S. Pat. No. 7,408,484, issued Aug. 5, 2008, entitled “Method of Doing Pack Unicode ZSeries Instructions,” by Rajendran et al., the entirety of each of which is hereby incorporated herein by reference.
BACKGROUND
The present invention relates in general to systems, program products and methods for emulating the computer instructions found in a source computer architecture in which sequences of instructions on a target machine architecture are generated so as to produce the same results on both computer architectures. More particularly, the present invention is related to methods and systems for emulating PACK instructions for Unicode character strings. Even more particularly, the present invention is directed to emulation methods in which computer instructions found on zSeries machines are emulated on other computer architectures, notably the Intel x86 series of microprocessors and the PowerPC series of microprocessors. The present description also includes methods and systems for emulating the PACK ASCII instruction.
As is well known, the Unicode standard for character representation is a two byte (“double byte” in some terminology) system in which each character is represented by 16 bits or two bytes of information. This standard provides a vastly expanded range of representable characters including those from languages in which ideographs are employed to represent words and ideas as opposed to the use of individual letters. This is in distinction to ASCII or EBCDIC character representations which provide a maximum of 255 characters or signal indicators.
It is also known that each byte (eight bits) in a data processing system can represent two decimal numbers. However, it is often the case that decimal numbers are provided in a format in which each byte contains a representation of but one decimal number. It is therefore convenient to be able to PACK decimal numbers (or other data) into a packed format, that is, from a one-decimal-digit-per-byte format to a two-decimal-digit-per-byte format. This is typically accomplished with some form of PACK instruction which is structured as a basic member of the set of a computer's instruction set. These instructions usually come in PACK/UNPACK pairs.
Also relevant to the present discussion are the notions of big-endian and small-endian. These concepts relate to the position in the memory architecture where the high order byte portion of an integer (or other data) is stored. In the big-endian scheme, the most significant byte of the integer is stored in the memory location with the lowest address. In the small-endian scheme, the most significant byte of the integer is stored in the memory location with the highest memory address. The Intel x86 processors and chips which seek to duplicate their functionality, such as those produced by Advanced Micro Devices, Inc., use the small-endian (also called little-endian) format. The zSeries of machines and most of the PowerPC devices employ the big-endian format.
PKU is an instruction present in the very well known zSeries computer architecture as found in products manufactured and sold by the assignee of the present invention. Descriptions of this and other instructions are found in any of the Principles of Operation (PoP) manuals published as accompanying documentation for the aforementioned data processing machine products. This particular instruction converts a Unicode string to a packed format. The format of the PKU instruction is “PKU TARGET, SOURCE (L2)” where L2 is the Length of the second operand (0≦L2≦63). The length of the target is always 16 bytes. A sample program included herein as Appendix I provides a description of an approach to providing emulation code for the PKU (Pack Unicode) instruction. Appendix I thus illustrates a block level algorithm that is used herein.
The format of the second operand is changed from Unicode to packed, and the result is placed at the first-operand location. The packed format is described in Chapter 8, “Decimal Instructions.”
The two-byte second-operand characters are treated as Unicode Basic Latin characters containing decimal digits, having the binary encoding 0000-1001 for 0-9, in their rightmost four bit positions. The leftmost 12 bit positions of a character are ignored. The second operand is considered to be positive.
The implied positive sign (1100 binary) and the source digits are placed at the first-operand location. The source digits are moved unchanged and are not checked for valid codes. The sign is placed in the rightmost four bit positions of the rightmost byte of the result field, and the digits are placed adjacent to the sign and to each other in the remainder of the result field.
The result is obtained as if the operands were processed right to left. When necessary, the second operand is considered to be extended on the left with zeros.
The length of the first operand is 16 bytes.
The byte length of the second operand is designated by the contents of the L2 field. The second-operand length must not exceed 32 characters or 64 bytes, and the byte length must be even (L2 must be less than or equal to 63 and must be odd); otherwise, a specification exception is recognized.
When the length of the second operand is 32 characters (64 bytes), the leftmost character is ignored.
PKU is described in the published description of the Pack Unicode instruction z/Architecture Principles of Operation having a document number of SA22-7832-03 with a “Build Date” of May 4, 2004 12:13:20 and a “Build Version” of 1.3.1 of “BUILD/VM Version: UG03935” and a Drop Date of Thursday Aug. 8, 2003.
PKA is a zSeries instruction that converts an ASCII string to packed format. The format of the PKA instruction is “PKA TARGET SOURCE (L2)” where L2 is the Length of the second operand (0≦L2≦31). The length of the target is always 16 bytes.
The format of the second operand is changed from ASCII to packed, and the result is placed at the first-operand location. The packed format is described in Chapter 8, “Decimal Instructions.”
The second-operand bytes are treated as containing decimal digits, having the binary encoding 0000-1001 for 0-9, in their rightmost four bit positions. The leftmost four bit positions of a byte are ignored. The second operand is considered to be positive.
The implied positive sign (1100 binary) and the source digits are placed at the first-operand location. The source digits are moved unchanged and are not checked for valid codes. The sign is placed in the rightmost four bit positions of the rightmost byte of the result field, and the digits are placed adjacent to the sign and to each other in the remainder of the result field.
The result is obtained as if the operands were processed right to left. When necessary, the second operand is considered to be extended on the left with zeros.
The length of the first operand is 16 bytes.
The length of the second operand is designated by the contents of the L2 field. The second-operand length must not exceed 32 bytes (L2 must be less than or equal to 31); otherwise, a specification exception is recognized.
When the length of the second operand is 32 bytes, the leftmost byte is ignored.
PKA is described in the published description of the Pack Unicode instruction found in the same published Principles of Operation manual cited above.
BRIEF SUMMARY
The algorithm discussed in detail below in the description section is a block by block algorithm useful for converting UNICODE strings to a packed format. The algorithm works on both big-endian and small-endian machines. When timed for performance, block by block algorithms are much faster when compared to byte-by-byte methods. The algorithm that was initially considered was a byte-by-byte approach which was later improved to the block-by-block method using 8 byte blocks at a time.
The algorithm discussed in detail below in the description section is a block by block algorithm to convert an ASCII string to a packed format. The algorithm works on both big-endian and small-endian machines. When timed for performance, block by block algorithms are much faster when compared to byte by byte methods. The algorithm that was initially considered was a byte-by-byte approach which was later improved to the block by block method using 8 byte blocks at a time.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention.
In accordance with one embodiment of the present invention as it relates to the PACK UNICODE instruction, there is provided a method for packing data from a Unicode field to a field which is approximately half as wide. First input data to be packed is retrieved from memory and stored in an offset position in memory locations which represent a local array of bytes. A source pointer is then set to point to the data at address “local array +2.” Additionally, a target pointer is set to point to a position in memory which represents a local pack array which holds operation results. The pack operation is carried out in blocks instead of in a byte-by-byte operation. In the block operation a first byte of the present block is determined in accordance with the following C language script as: (((BLOCK & 0x000F000F000F000F)<<12)|((BLOCK & 0x000F000F000F000F)<<24)) & 0xFF0000000000000), where “BLOCK” represents the current block of input data being processed. The three remaining bytes of the present block are then generated by shifting and then ORing the byte to the 4-byte output block. The pointers are incremented and the steps are repeated four times, once for each block. Lastly, the last nibble is set to 0xC and the pack array is stored in memory. A nibble is a four bit data portion typically represented by a single hexadecimal digit.
The recitation herein of a list of desirable objects which are met by various embodiments of the present invention is not meant to imply or suggest that any or all of these objects are present as essential features, either individually or collectively, in the most general embodiment of the present invention or in any of its more specific embodiments.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, both as to organization and method of practice, together with the further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which:
FIG. 1 is a block diagram illustrating the environment in which the present invention operates and is employed;
FIG. 2 is a block diagram illustrating the structure of a 64 byte chunk of Unicode structured data;
FIG. 3 is a block diagram more particularly illustrating the structure of a single byte of the rightmost portion of a Unicode character, that is, the rightmost of its two bytes and particularly showing its structure as two nibbles;
FIG. 4 is a block diagram illustrating the structure of Unicode originated data after its packed into a digits-only format together with a sign nibble;
FIG. 5 is a top view of a typical computer readable medium containing program code which implements the methods of the present invention, as for example, as shown a Compact Disc (CD);
FIG. 6 is a block diagram illustrating the method employed for emulating the PKU instruction;
FIG. 7 is a block diagram illustrating the method employed for emulating the PKA instruction; and
FIG. 8 is a block diagram illustrating an example of the environment in which the present invention is employed.
DETAILED DESCRIPTION
The typical emulation environment in which the present invention is employed is illustrated in FIG. 1 . Emulators such as 320 accept as input instruction streams 305 , representing machine or assembly language instructions which are designed to operate on source machine 300 . Emulator 320 employs memory 315 in target machine 310 to produce a stream of instructions which are capable of executing on target machine 310 . While FIG. 1 particularly shows operation within an emulation environment, it is also noted that the present invention contemplates a situation in which emulator 320 operates essentially as an interpreter in which the instructions are not only translated to the new architecture but in which they are also executed at essentially the same time.
Also, since the present invention is particularly concerned with packing instructions, FIG. 2 is provided so as to illustrate the structure of data which is typically supplied to a pack type of instruction. In particular, FIG. 2 illustrates the structure of 64 bytes of data representing 32 Unicode characters. In the present invention, data of this type would be processed in blocks of 16 bytes each. The “x” that is shown in the rightmost portion of each Unicode character (32 of them in all) represents that portion of a Unicode character which includes the encoding for a decimal digit (and more too which is ultimately discarded). The structure of such a rightmost Unicode character is more particularly illustrated in FIG. 3 in which it is seen that each of byte “x” is divided into two nibbles, an upper portion “u” and a lower or digit portion “d.” These figures are presented this way due to size limitations as to the detail needed. In the PACK Unicode, instruction considered herein, the packaging process results in a structure such as that shown in FIG. 4 in which each of the digit nibbles are packed two-to-a-byte in a 16 byte block with the rightmost nibble of this block including the sign nibble.
As pointed out above, the method of the present invention is embodied in its preferred form in the programming code set forth in the appendices one and two herein. Such programming is typically provided on a computer readable medium such as disk 600 shown in FIG. 5 . However, it is also contemplated that such programming may also be distributed over any convenient data processing network.
The description of the emulation method for the PKU and the PKA instructions are discussed below. In this description, it is noted that reference to zMemory refers to memory locations in the target system which are employed for the purposes of the emulation process especially when the target machine has the zSeries architecture. However, it is noted that, in the methods provided below, zMemory is really just an exemplar and that any suitable memory in the target machine may be employed for this purpose.
As a further preliminary matter, in the description below: the symbol “&” represents a logical bitwise AND operation; the symbol “|” represents a logical bitwise OR operation; the symbol “<<” represents a logical bit wise LEFT SHIFT operation with the number to the right of “<<” indicating the number of bit positions to be shifted; and “0 x” represents any single hexadecimal (four bit) digit (0000 through 1111); and “0F” represents the four bit hexadecimal digit which is all ones (that is, 1111) with “00” thus representing the hexadecimal digit which is all zeroes (that is, 0000).
The PKU instruction is discussed first.
PKU Instruction
The method described below is described in the C programming language and it works on both PowerPC-AIX (big endian) and Intel-L1NUX (small endian) architectures. The method described below is also shown in flow chart form in FIG. 6 wherein the step numbers are labeled as they are below. The block-by-block processing (as opposed to byte-by-byte processing) is carried out as follows:
(Step 105 ) Fetch input from zMemory to local array of size 66 bytes using proper offset; that is, copy L2 bytes from zMemory into local array+(64−L2).
(Step 110 ) Set source pointer to point to (local array+2). The source pointer type is unsigned long long (for 8 byte processing).
(Step 115 ) Set target pointer to point to pack array. The target pointer type is int (for 4 byte processing).
Do the Steps 130 and 135 below four times, each time in the loop operating on the 16-byte input block to get 4 bytes of output (Block 125 in FIG. 6 ). Block 120 in FIG. 6 represents the return point for this loop which passes through “counter” 150.
(Step 130 ) The first byte of output is computed as follows:
(((BLOCK & 0x000F000F000F000F)<<12)|((BLOCK & 0x000F000F000F000F)<<24)) & 0xFF00000000000000); <<=this will be the first byte of output;
(Step 135 ) Get the three remaining bytes of output by shifting appropriately and then OR the byte to the 4-byte output block.
(Step 140 ) Set the last nibble to 0xC for a positive sign.
(Step 145 ) Store the pack array into zMemory.
The present method uses byte reversal functions whenever required to support both big-endian and little-endian architectures. The architecture for the most relevant source architecture, the zSeries of machines, is big-endian. Sample C code is given below in Appendix I where the input is assumed to be 64 bytes in length. Modifications to this code to accommodate other lengths is easily discerned.
PKA Instruction
The method described below is described in the C programming language and it works on both PowerPC-AIX (big endian) and Intel-LINUX (small endian) architectures. The referenced method is also shown in flow chart form in FIG. 7 wherein the step numbers are labeled as they are below. The block-by-block processing (as opposed to byte-by-byte processing) is carried out as follows:
(Step 205 ) Copy input from zMemory to local array of size 33 bytes using proper offset; that is, copy L2 bytes from zMemory into local array+(32-L2).
(Step 210 ) Set source pointer to point to local array+1 and is of type unsigned long long (for 8 byte processing)
(Step 215 ) Set target pointer to point to pack array and is of type int (for 4 byte processing).
Do the Steps 230 and 235 below four times, each time in the loop operating on the 8-byte input block to get 4 bytes of output (Block 225 in FIG. 7 ). Block 220 in FIG. 7 represents the return point for this loop which passes through “counter” 250 .
(Step 225 ) Each time in the loop operate on the 8-byte input block to get 4 bytes of output;
(Step 230 ) The first byte of output is calculated as follows:
(((BLOCK & 0x0F0F0F0F0F0F0F0F)<<4)|((BLOCK & 0x0F0F0F0F0F0F0F0F)<<4)) & 0xFF00000000000000);
(Step 235 ) Get the 3 remaining bytes of output by shifting appropriately and OR the byte to the 4-byte output block.
(Step 240 ) Set the last nibble to 0xC for positive sign.
(Step 245 ) Store pack array into zMemory
As above, to accommodate different architectures, when fetching and storing, byte reversal functions are used for big-endian and small-endian formats.
In any event the environment in which the present invention operates is shown in FIG. 8 . The present invention operates in a data processing environment which effectively includes one or more of the computer elements shown in FIG. 8 . In particular, computer 500 includes central processing unit (CPU) 520 which accesses programs and data stored within random access memory 510 . Memory 510 is typically volatile in nature and accordingly such systems are provided with nonvolatile memory typically in the form of rotatable magnetic memory 540 . While memory 540 is preferably a nonvolatile magnetic device, other media may be employed. CPU 530 communicates with users at consoles such as terminal 550 through Input/Output unit 530 . Terminal 550 is typically one of many, if not thousands, of consoles in communication with computer 500 through one or more I/O unit 530 . In particular, console unit 550 is shown as having included therein a device for reading medium of one or more types such as CD-ROM 600 shown in FIG. 5 . Media 600 may also comprise any convenient device including, but not limited to, magnetic media, optical storage devices and chips such as flash memory devices or so-called thumb drives. Disk 600 also represents a more generic distribution medium in the form of electrical signals used to transmit data bits which represent codes for the instructions discussed herein. While such transmitted signals may be ephemeral in nature they still, nonetheless constitute a physical medium carrying the coded instruction bits and are intended for permanent capture at the signal's destination or destinations.
APPENDIX I
#include <stdio.h>
#include <time.h>
#include <byteswap.h>
#define ntohll(x) bswap_64(x)
#define htonll(x) bswap_64(x)
main( )
{
char input[66]= {0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,
0x38,0x39,0x3A,0x3B,0x3C,0x3D,0x3E,0x3F,
0x3F,0x3E,0x3D,0x3C,0x3B,0x3A,0x39,0x38,
0x37,0x36,0x35,0x34,0x33,0x32,0x31,0x39,
0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,
0x38,0x39,0x3A,0x3B,0x3C,0x3D,0x3E,0x3F,
0x3F,0x3E,0x3D,0x3C,0x3B,0x3A,0x39,0x38,
0x37,0x36,0x35,0x34,0x33,0x32,0x31,0x39,
0x00,0x00};
char pack_array[16]= { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
short int i;
unsigned int *optr=(unsigned int *)pack_array;
unsigned long long *iptr=(unsigned long long *)(input+2;
for (i=0;i<4;i++,optr++,iptr=iptr+2)
{
*optr = htonl((((((ntohll(*iptr) & 0x000F000F000F000FULL) << 12) |
((ntohll(*iptr) & 0x000F000F000F000FULL) << 24))) &
0xFF00000000000000ULL) |
((((((ntohll(*iptr) & 0x000F000F000F000FULL) << 12) |
((ntohll(*iptr) & 0x000F000F000F000FULL) << 24))) &
0x00000000FF000000ULL) << 24) |
((((((ntohll(*(iptr+1)) & 0x000F000F000F000FULL) << 12) |
((ntohll(*(iptr+1)) & 0x000F000F000F000FULL) << 24))) &
0xFF00000000000000ULL) >> 16) |
(((((((ntohll(*(iptr+1)) & 0x000F000F000F000FULL) << 12) |
((ntohll(*(iptr+1)) & 0x000F000F000F000FULL) << 24))) &
0x00000000FF000000ULL)) << 8)) >> 32;
}
optr--;
*optr = htonl((ntohl(*optr) & 0xFFFFFFF0) | 0xC);
}
APPENDIX II
#include <stdio.h>
#include <time.h>
#include <byteswap.h>
#define ntohll(x) bswap_64(x)
#define htonll(x) bswap_64(x)
main( )
{
char input[33] = {
0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,
0x38,0x39,0x3A,0x3B,0x3C,0x3D,0x3E,0x3F,
0x3F,0x3E,0x3D,0x3C,0x3B,0x3A,0x39,0x38,
0x37,0x36,0x35,0x34,0x33,0x32,0x31,0x39,
0x00};
char pack_array[16] = {
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
short int i;
unsigned long long *iptr = (unsigned long long *)(input+1);
unsigned int *optr = (unsigned int *)pack_array;
for (i=0;i<4;i++,optr++,iptr++)
{
*optr = htonl((((((ntohll(*iptr) & 0x0F0F0F0F0F0F0F0FULL) |
((ntohll(*iptr) & 0x0F0F0F0F0F0F0F0FULL) << 4)) << 4) &
0xFF00000000000000ULL) |
(((((ntohll(*iptr) & 0x0F0F0F0F0F0F0F0FULL) |
((ntohll(*iptr) & 0x0F0F0F0F0F0F0F0FULL) << 4)) << 4) &
0x0000FF0000000000ULL) << 8) |
(((((ntohll(*iptr) & 0x0F0F0F0F0F0F0F0FULL) |
((ntohll(*iptr) & 0x0F0F0F0F0F0F0F0FULL) << 4)) << 4) &
(((((ntohll(*iptr) & 0x0F0F0F0F0F0F0F0FULL) |
((ntohll(*iptr) & 0x0F0F0F0F0F0F0F0FULL) << 4)) << 4) &
0x00000000FF000000ULL) << 16) |
(((((ntohll(*iptr) & 0x0F0F0F0F0F0F0F0FULL) |
((ntohll(*iptr) & 0x0F0F0F0F0F0F0F0FULL) << 4)) << 4) &
0x000000000000FF00ULL) << 24)) >> 32);
}
optr--;
*optr = htonl((ntohl(*optr) & 0xFFFFFFF0) | 0xC);
}
While the invention has been described in detail herein in accordance with certain preferred embodiments thereof, many modifications and changes therein may be effected by those skilled in the art. Accordingly, it is intended by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention. | Emulation methods are provided for two PACK instructions, one for Unicode data and the other for ASCII coded data in which processing is carried out in a block-by-block fashion as opposed to a byte-by-byte fashion as a way to provide superior performance in the face of the usual challenges facing the execution of emulated data processing machine instructions as opposed to native instructions. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improvement in the structural arrangement of an electromagnetically operated shutter for a camera.
2. Description of the Prior Art
Generally, an electromagnetically operated shutter uses an electromagnetic force for driving shutter blades. The electromagnetic force F is expressed as F=BIL and is proportional to magnetic flux density (B), a current (I) and coil length (L) respectively. In order that every electromagnetically operated shutter to be manufactured have a uniform driving force, therefore, the magnetic flux density, the current and the coil length must be kept in an unvaried condition. As for the coil length, it is possible to wind or pattern a coil to an undeviating uniform length so that coils of uniform length can be always obtained. It is also possible to obtain an undeviating value of current through an electric circuit. However, it has been impossible to obtain a uniform degree of magnetic flux density for every shutter manufactured because of a problem relative to positioning a permanent magnet. In other words, in the conventional electromagnetically operated shutter, a permanent magnet is arranged without placing it in a fixed position on a magnetic base plate used for forming a magnetic circuit. Therefore, the permanent magnet and the coil of one shutter have differed in position from those of another shutter. Besides, a spacer or the like inserted in a space between the permanent magnet and a yoke to form "a gap of a magnetic circuit" has made it difficult to attain dimensional precision. This difficulty has furthered the unevenness of shutters in respect to magnetic flux density and also has complicated assembling work.
Further, to better the dynamic characteristic of a shutter, it is advantageous to have a greater driving force. In view of this, a uniform high magnetic flux density has been obtained in practice by using a stronger permanent magnet. The use of a strong permanent magnet, however, presents a problem in that the magnetic flux might leak to some parts outside of the magnetic circuit. Such a magnetic flux leakage tends to magnetically affect other parts of the camera such as a shutter control circuit, and thus tends to cause troubles in shutter control, etc.
The degree of overlapping of shutter blades hardly can be made uniform among shutters due to manufacturing errors, etc. Then, the uneven overlapping of shutter blades makes the dynamic characteristic, in the initial stage of movement, of one shutter different from that of another. This results in an exposure error. It is, therefore, necessary to have the overlapping of the shutter blades adjusted to a uniform degree by means of an adjusting member. Then, with such an adjusting member used for an electromagnetically operated shutter of the above stated type, it is necessary to have the adjusting member disposed on the base plate which forms a magnetic circuit. The adjusting member is to be adjusted with some tool such as a screw driver upon completion of shutter assembly. If the adjusting tool is made of a magnetic material, there would take place an attraction between the tool and the base plate which forms the magnetic circuit. The attraction would hinder the adjusting work. Then, if the work must be done with a tool made of a non-magnetic material, it necessitates selection of such a tool solely for the adjusting work on this part while other parts of a camera are assembled and adjusted with tools made of a magnetic material. This complicates the work. Further, even if a tool made of any material is used as desired, magnetic dust sticking to the tool would still be attracted to the base plate around the adjusting member during the adjusting work thereon, and then might remain there after adjustment to hinder the rotation of the rotor or the movement of the shutter blades.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an electromagnetically operated shutter device which eliminates the above stated shortcomings of the conventional shutters, including a magnetic body, permanent magnets for providing a magnetic circuit within the magnetic body, and a positioning member which is arranged to position the permanent magnets within the magnetic body. A frame is formed to surround the positioning member, and a shutter driving rotor is disposed in a gap formed between the frame of the positioning member and a part of the magnetic body. Accordingly, positioning of the permanent magnets, and forming a gap in the magnetic circuit are accomplished simultaneously.
It is another object of the invention to provide an electromagnetically operated shutter device including a magnetic piece on the magnetic body to form a magnetic path, and an adjusting member for adjustment of the extent to which shutter members or blades overlap, wherein the adjusting member is magnetically shielded by the magnetic path formed with the magnetic piece.
These and further objects, features and advantages of the invention will become apparent from the following detailed description of an embodiment thereof taken in connection with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view showing an electromagnetically operated shutter as an embodiment of the present invention.
FIG. 2 is a detail view of a rotor and shutter blades shown in FIG. 1.
FIG. 3 is a sectional view showing the assembly of the shutter shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the embodiment of the present electromagnetically operated shutter device shown in FIG. 1, which is an exploded view showing the essential components of the embodiment, a first base plate 11 is attached to a camera body (not shown). A second base plate 12 is made of a magnetic material. The first and second base plates 11 and 12 are mounted with screws 13. Between the first and second base plates 11 and 12, there are provided a shutter opening restricting member 14; three shutter blades 15, 16 and 17 which are made of a synthetic resin; a guide plate 18 which is made of a magnetic material; a rotor 19; permanent magnets 20a, 20b, 20c and 20d; and a positioning member 21 which is made of a non-magnetic material such as a plastics material. Each of the first base plate 11, the restricting member 14, the guide plate 18, the rotor 19, the positioning member 21 and the second base plate 12 is provided with an opening for allowing light to pass therethrough. Meanwhile, there is provided a shutter blade assembly which consists of the three shutter blades 15, 16 and 17 and is arranged to block the passage of the light. These shutter blades 15, 16 and 17 are disposed between the first base plate 11 and the guide plate 18 together with the restricting member 14. The guide plate 18 is provided with spacers 18a and 18b which define a movable space for these blades. Around the opening of the guide plate 18, there extend pins 18c, 18d and 18e which serve as rotation shafts for the shutter blades. These pins 18c, 18d and 18e are arranged to pierce through the shutter blades and the restricting member 14 and are inserted into holes provided in the first base plate 11. In the guide plate 18, there are provided guide slots 18f, 18g and 18h which are arranged to have pins 19a, 19b and 19c extending from the rotor 19 inserted therein. The pins 19a, 19b and 19c extending from the rotor 19 are arranged to serve as driving shafts for driving the shutter blades 15, 16 and 17. The rotor 19 is provided with a coil 19d. The positioning member 21 is provided with holes 21a, 21b, 21c and 21d for inserting therein the permanent magnets 20a, 20b, 20c and 20d which are magnetized in the direction of thickness of the plate; a spring retainer 21f for a spring 21e which is arranged to urge the rotor to rotate clockwise; a support 21g for supporting the rotor 19; and a surrounding frame 21h which is formed into one unified body with the positioning member 21. The spring retainer 21f is arranged to serve also as a positioning pin and to protrude not only on the forward surface of the positioning member 21 but also protrude from the reverse side thereof. The spring retainer 21f is thus inserted into a hole 18i of the guide plate 18 and also into a hole 12c provided in the second base plate 12. As shown in FIG. 3, the frame 21h has a total thickness t and forms a gap of width g between the positioning member 21 and the guide plate 18. With this gap provided by the frame 21h between the guide plate 18 and the positioning member 21, dust is effectively prevented from entering into the shutter. Further, on the reverse sides of the positioning member 21 and the spacers 18a and 18b, there are provided protrusions 21i, 21j, 18a1 and 18b1 which permit the rotor 19 to rotate without coming into contact directly with the magnets 20a, 20b, 20c and 20d and the guide plate 18. The support 21g is arranged into two steps for insertion into the openings provided in the rotor 19 and the guide plate 18, while the support 21g is also arranged to be inserted into the second base plate on the reverse side of the positioning member 21.
On the second base plate 12, there is provided an eccentric pin 12a which is arranged to serve as an adjusting member for adjustment of the extent to which the shutter blades 15, 16 and 17 overlap each other. This eccentric pin 12a is positioned in the cutaway part 21k of the positioning member 21 and an adjusting hole 18l of the guide plate 18 communicating with the guide slot 18g while the pin 12a is in contact with the rotor 19 as shown in FIG. 2. In FIG. 2, the illustration omits an auxiliary stop 15a (FIG. 1). The eccentric pin 12a is arranged to be adjusted by inserting a tool such as a screw driver through an adjusting hole provided in the first base plate 11. A bent piece 18j is taken out from a part of the guide plate 18 around the adjusting hole 18l provided therein. This bent piece 18j is arranged to abut on the second base plate 12 through the cutaway part 21k as shown in FIG. 3. This bent piece 18j is provided for the purpose of eliminating any magnetic effect on the eccentric pin 12a. With the bent piece 18j arranged in this manner, a magnetic path is formed between the guide plate 18 and the second base plate 12 to magnetically shield the eccentric pin 12a. There is provided a printed circuit board 22 which has a light sensitive element 23 disposed thereon. The light sensitive element 23 is arranged to have light guided thereto through the cutaway part 11b of the first base plate 11, the auxiliary stop 15a, the cutaway part 18k of the guide plate 18, the window 21l provided in the positioning member 21 and the cutaway part 12b of the second base plate 12. The auxiliary stop 15a is provided in one end part of the shutter blade 15 and is arranged to control the quantity of the light arriving at the light sensitive element in accordance with the action of the adjoining shutter blade 17. On the reverse side of the printed circuit board 22, there is provided a shutter control circuit element 24 as shown in FIG. 3. This circuit element 24 is located on the reverse side of the second base plate 12 to avoid a magnetic effect on the circuit element. In FIG. 3, there is shown only one shutter blade, while other shutter blades are omitted from the illustration.
In manufacturing the shutter, the permanent magnets 20a, 20b, 20c and 20d are inserted in the holes 21a, 21b, 21c and 21d of the positioning member 21. The spring 21e is engaged with the spring retainer 21f. The opening of the rotor 19 is fitted onto the first step of the support 21g. Then, the spring 21e is applied to the rotor 19 to bring it into a state of being turned clockwise. The spring retainer 21f is then inserted into the hole 18i of the guide plate 18 to effect positioning. Then, the opening of the guide plate 18 is fitted onto the second step of the support 21g in such a way as to have the pins 19a, 19b and 19c inserted into the guide slots 18f, 18g and 18h of the guide plate 18. The second base plate 12 is fitted onto the protrusion of the spring retainer 21f protruding on the reverse side of the positioning member 21 for positioning. Following this, the shutter blades 15, 16 and 17 are placed on the pins 18c, 18d, 18e, 19a, 19b and 19c and then the restricting member 14 is fitted onto the pins 18c, 18d and 18e. Last, the pins 18c, 18d, 18e, 19a, 19b and 19c are inserted into the corresponding holes of the first base plate 11. Then the first and second base plates 11 and 12 are fixed to each other by screws. The shutter assembled in this manner is shown in FIG. 3.
During the manufacture of the shutter, positioning of the permanent magnets is effected by inserting the permanent magnets 20a, 20b, 20c and 20d into the holes 21a, 21b, 21c and 21d of the positioning member 21, so that the permanent magnets can be set in a predetermined position without deviation. The rotor 19 is positioned with its opening fitted onto the first step part of the support 21g and is kept in this position with the guide plate 18 mounted. Therefore, the coil 19d of the rotor 19 and the permanent magnets 20a, 20b, 20c and 20d are kept in a stable positional relation to each other. Further, the gap between the guide plate 18 and the permanent magnets 20a, 20b, 20c and 20d is kept unvaried by the frame 21h, so that the magnetic flux density of the shutter can be uniformly arranged with the gap of the magnetic circuit always maintained constant. Further, since the space between the positioning member 21 and the guide plate 18 is arranged to be encased, dust is effectively prevented from entering there. The holes for positioning the permanent magnets, the support for the rotor 19 and the frame for forming the gap g are arranged into one unified body to form the positioning member to ensure dimensional precision in the manufacture of the shutter.
The electromagnetically operated shutter which is represented by the exploded view in FIG. 1 is assembled as shown in FIG. 3. Then, since the bent piece 18j of the guide plate 18 is abutting the second base plate 12, there is formed a magnetic path between the guide plate 18 and the second base plate 12 to magnetically shield the eccentric pin 12a. This arrangement eliminates the magnetic effects of the guide plate 18 and the base plate 12 in the vicinity of the eccentric pin 12a, so that magnetic dust sticking to a tool can be prevented from being attracted by the guide plate 18 and the second base plate 12 in the vicinity of the eccentric pin 12a. Even if a tool made of a magnetic material is used, the tool will never be attracted so that adjusting work can be easily accomplished. The extent to which the shutter blades are arranged to overlap each other is adjusted by turning the eccentric pin 12a to adjust the starting position of the rotor 19. Since the shutter control circuit element 24 is disposed on the reverse side of the second base plate 12 which forms a magnetic circuit, the circuit element 24 is free from any magnetic influence.
With the shutter in a closed state, when a current is allowed to flow to the coil 19d in the direction of the arrows shown in FIG. 1, there is generated an electromagnetic force in accordance with Fleming's left-hand rule. Then, the rotor 19 rotates counterclockwise against the pressure of the spring 21e to open the shutter blades 15, 16 and 17. Then, since the outer circumference of the shutter blades 15, 16 and 17 is larger than the diameter of aperture 14d for the light flux, the shutter blades 15, 16 and 17 open without colliding against the aperture 14d. Further, at this time, the rotor 19 begins to rotate from a position at which it has been adjusted by the eccentric pin 12a. Therefore, the dynamic characteristic at the start of the movement of the shutter blades is unvarying. With the shutter blades 15, 16 and 17 opened in this manner, there is effected an exposure. Then, the power supply to the coil 19d of the rotor 19 is cut off after a length of time determined by the shutter control circuit element 24 in accordance with the output of the light sensitive element 23. The electromagnetic force generated at the coil 19d then decays. The rotor 19 is rotated clockwise by the spring 21 to close the shutter blades.
In accordance with the invention, since the positioning member is formed into one unified body as mentioned in the foregoing, the dimensional precision of shutters can be made uniform. Magnetic flux density can be stabilized and shutter assembly can be facilitated. The rotor is encased with the positioning member and the guide plate, so that dust can be effectively prevented from entering there. The rotor which is disposed for movement within a working space has few parts that might come into contact with other parts. Therefore, it has little friction to enhance the kinetic characteristic of the shutter.
Between the first and second magnetic plates which form a magnetic circuit with permanent magnets for rotating the shutter driving rotor, there is provided a magnetic piece to form a magnetic path. This magnetic path is used to magnetically shield the adjusting member which is provided for adjustment of the extent to which the shutter blades are allowed to overlap each other. Therefore, when the adjusting member is adjusted by a tool, magnetic dust sticking to the tool is never attracted to the first and second magnetic plates in the vicinity of the adjusting member. Even if the tool is made of a magnetic material, the tool would not be attracted, so that the shutter assembling operation can be accomplished without difficulty. Further, since the shutter control circuit is disposed behind the magnetic plate, the circuit is magnetically shielded to allow it to perform shutter control with a high degree of accuracy. | An electromagnetically operated shutter device includes a magnetic body and permanent magnets which form a magnetic circuit in the magnetic body. A positioning member for seating the magnets within the body is made of a non-metallic material, and is formed of a support structure and a frame. A gap is formed by the frame between the positioning member and the magnetic body, and a shutter drive motor is disposed in the gap and is rotatably held by the support structure. According to one embodiment, an adjusting member is arranged on the body for adjusting the extent to which shutter blades driven by the rotor overlap one another. The adjusting member is magnetically shielded by a magnetic path which is formed by a part of the magnetic body. | 6 |
This application claims priority to International Application No. PCT/EP20089/002334 filed on Mar. 31, 2009, under Section 371 and/or as a continuation under Section 120, which in turn claims priority to U.S. Provisional Patent Application No. 61/040,751 and to German Patent Application No. 10 2008 016 462.3, both filed on Mar. 31, 2008.
TECHNICAL FIELD
The invention relates to a climate tube, in particular for aircraft, having an inner layer and an outer layer of fiber composite plastic material.
BACKGROUND
Climate tubes of this type are well-known for example in aircraft construction and form a part of the air-conditioning system of an aircraft. Climate tubes are used for example to carry heated air from a processing unit, a so-called air-conditioning pack, into the cabin of an aircraft. It has hitherto been customary to manufacture climate tubes from a plurality of thin plies of a fiber composite plastic material, so-called prepregs. The number of material plies used was geared to the stability requirements to be demanded of a given climate tube.
Climate tubes for supplying fresh air have to be insulated to prevent undesirable condensation on the pipe surfaces in the aircraft. For this reason, flexible foam of a suitable thickness is conventionally fitted onto the outside of climate tubes of prior art.
In order to fasten conventional climate tubes for example in an aircraft, the pipes are fixed by means of pipe clamps to supports that are connected to the aircraft structure. If the climate tube is externally insulated with foam, the pipe fastening has to comprise a spacer profile to minimize heat conduction between the aircraft structure and the pipe body, i.e. to guarantee a thermally isolated fastening of the pipe to the aircraft structure.
The underlying object of the invention is to provide an improved climate tube that is suitable in particular for use in aircraft.
SUMMARY OF THE INVENTION
This object is achieved according to the invention by a climate tube having the features described below. In the case of the climate tube according to the invention, disposed between the inner and the outer layer of fiber composite plastic material is an at least almost completely circumferential honeycomb core, which is connected to the inner and the outer layer and the radial extent of which is large compared to the radial extent of the inner and outer layer. By this it is meant that the radial extent of the honeycomb core is several times as great as the thickness of the inner or outer layer. Preferably the radial dimension of the honeycomb core is at least five times as great as the thickness of the inner layer or the outer layer, however the radial dimension of the honeycomb core may easily be even eight times, ten times or fifteen times greater than the thickness of one of the two covering layers. The thickness (radial dimension) of the honeycomb core of a climate tube according to the invention results, on the one hand, from stability requirements and, on the other hand, from the required insulation of the climate tube. If the thickness of the honeycomb core is selected so as to correspond at least approximately to the thickness of the foam material layer previously required for insulation purposes, then an equivalent insulating effect results. Applying a foam material layer onto the climate tube is therefore no longer necessary.
The inner layer and the outer layer, which may also be referred to as covering layers, may be glass fiber- and/or carbon fiber-reinforced composite laminates impregnated with synthetic resin. Such a composite laminate is frequently referred to as a prepreg. The honeycomb core may comprise for example paper honeycombs impregnated with synthetic resin.
A climate tube according to the invention has several advantages over conventional climate tubes: because of the honeycomb core it is markedly stiffer and therefore deforms much less in the event of compression loading (internal or external pressure). The increased stability achieved by the sandwich structure (inner layer, honeycomb core, outer layer) moreover enables a climate tube according to the invention itself to be used as a support for further systems, for example a further climate tube may be fastened to a climate tube according to the invention and need not, as is customary, be separately connected to the aircraft structure. In climate tubes that are subject to low pressure, the number of material plies of fiber composite plastic material may be markedly reduced because the honeycomb core leads to an overall stiffness that, even without many plies of fiber composite plastic material, is equal to or better than that of conventional climate tubes. As the honeycomb core moreover has a lower mass per unit area, low-pressure climate tubes according to the invention are also lighter than was previously customary. Finally, as already mentioned, it is possible to dispense with the foam material previously required for insulation purposes, because the honeycomb core, given a suitable design (i.e. a suitable thickness), has an equivalent insulating effect.
To facilitate bending of the honeycomb core into the pipe shape, in preferred embodiments of the climate tube according to the invention the honeycomb core is pre-stretched and/or expanded in a direction transversely of the longitudinal extent of the individual honeycombs. The cross section of the individual honeycombs of the honeycomb core is consequently deformed in an oblong manner and may therefore adapt better to the curvature needed to achieve the pipe shape. During bending of the honeycomb core into the pipe shape there occurs, above an imaginary center plane of the honeycomb core, an elongation of the pre-stretched side walls and, below the imaginary center plane, a compression of the pre-stretched side walls of each honeycomb.
The inner and outer layer of fiber composite plastic material are each formed by at least one material ply. Should it be desirable for the sake of stability, the inner layer and/or the outer layer may each comprise a plurality of material plies.
The forming of the honeycomb core into the pipe shape results in two longitudinally extending abutting edges. These abutting edges are preferably surrounded by a ply of fiber composite plastic material in order to protect the structure of the honeycomb core and enable a good connection of the two abutting edges. To increase the overall strength of the climate tube, in preferred developments thereof it is contemplated that in the region of the previously mentioned, longitudinally extending abutting edges at least two material plies of the inner layer overlap.
In a preferred development of a climate tube according to the invention, on the exterior thereof an additional pipe is fastened directly, i.e. without a support. In particular, the direct fastening of the additional pipe may be effected by means of an adhesive join. The additional pipe may be used for example to carry a branched-off air stream to sensor equipment in order to measure the temperature or the moisture content of the air stream or the like. The additional pipe may also be used to accommodate electric control lines. In a particularly preferred development, the additional pipe is disposed partially embedded in the exterior of the climate tube, i.e. it is partially countersunk in the exterior of the climate tube. The extent of the embedding in the exterior in this case does not lead to a reduction of the thickness of the honeycomb core of the climate tube, rather there is merely a displacement into the opening cross section of the climate tube, so that the extent of the embedding in the exterior correspondingly reduces the opening cross section at the interior of the climate tube. The wall thickness of the climate tube in the region of the external embedding therefore remains identical to the wall thickness of the climate tube in regions without external embedding. Besides the space saved and the reduction of components achieved by this solution, a precise positioning of the additional pipe is also guaranteed without special mounting devices such as supports or the like being used.
The cross section of a climate tube according to the invention is preferably circular, oval or elliptical, but may also assume other cross-sectional shapes. With the climate tube according to the invention it is also possible to make the cross section vary over its length. For example, the cross section of a climate tube according to the invention may be initially circular, then oval or elliptical and finally, if desired, become circular again. By suitable stretching and elongation of the honeycomb core, such variations in the cross section may be realized without sacrificing the stability of the climate tube.
Preferred embodiments of climate tubes according to the invention are developed to support a further climate tube. According to an embodiment, this is achieved by means of an insert, which is fastened in the honeycomb core of the climate tube and which at its side projecting from the climate tube is adapted to support a further climate tube, for example by means of a pipe clamp. According to another embodiment, a support, for example a clamp-type support, is fastened on the climate tube and may support a further climate tube.
Climate tubes according to the invention however also allow the integral construction of an additional duct or a plurality of additional ducts. If the additional duct need have only a small cross section, such an additional duct may be formed by a recess of the honeycomb core that extends in longitudinal direction of the climate tube. In other words, the additional duct then extends inside the wall of a climate tube according to the invention. Such an additional duct may be used to receive a flowing fluid, but may also be used equally well to accommodate electric or other lines.
If the additional duct is to have a larger cross section, then, in addition to the recess of the honeycomb core that extends in longitudinal direction of the climate tube, the outer layer of fiber composite plastic material may also be recessed. In the recess thus achieved, which extends in longitudinal direction of the climate tube, a partial-pipe-shaped insert part having the desired free cross section may then be fastened, for example by glueing. Depending on the required purpose, the wall of the partial-pipe-shaped insert part may be constructed in an identical manner to the climate tube itself, i.e. with a honeycomb core. Alternatively, the wall of the partial-pipe-shaped insert part may however merely comprise one or more plies of fiber composite plastic material. The opening cross section of the partial-pipe-shaped insert part may differ in shape from that of the climate tube and be in particular of a flatter design. Despite the partially recessed honeycomb core, such a climate tube having one or more additional ducts has a high stability.
Finally, a climate tube according to the invention, independently of whether or not it has an additional duct as described above, may be subdivided in longitudinal direction by means of at least one dividing wall. This allows for example intake air and discharged air to be carried separately from one another in a single climate tube. The dividing wall and/or the dividing walls, which may take the form of sandwich webs, are easily capable of withstanding pressure differences between individual fluid streams and providing thermal insulation between the individual fluid streams. If thermal insulation is not required, the dividing wall or the dividing walls may also be made of simple fiber composite plastic material.
The manufacture of climate tubes according to the invention is effected in principle in exactly the same way as the manufacture of sandwich panels with a honeycomb core that are frequently used in aircraft construction. More precisely, the inner layer, the honeycomb core and the outer layer are placed successively into a mould, the mould is then closed and subsequently heated in order to bake the inner layer, the honeycomb core and the outer layer to one another. After cooling, the finished climate tube forming a structural unit may be removed from the mould.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of climate tubes according to the invention are described in detail below with reference to diagrammatic figures. These show:
FIG. 1A a cross section through a first embodiment of a climate tube according to the invention having an oval cross section;
FIG. 1B a representation similar to FIG. 1A of a second embodiment having a circular-cylindrical cross section,
FIG. 2 an enlarged view of the connecting region of two longitudinally extending abutting edges of a climate tube according to the invention,
FIG. 3 a climate tube similar to FIG. 1A with a support for a further climate tube,
FIG. 4A a perspective view of a climate tube similar to FIG. 1A with an additional pipe fastened directly to the exterior of the climate tube,
FIG. 4B in cross section a sub-region of the embodiment shown in FIG. 4A ,
FIG. 5 a three-dimensional view of a climate tube having a large and a small additional duct, and
FIG. 6 a three-dimensional view of a climate tube similar to FIG. 1A , the interior of which is subdivided into three chambers by means of two dividing walls extending in longitudinal direction.
DETAILED DESCRIPTION
FIGS. 1A and 1B show in cross section two embodiments of a climate tube 10 that is suitable in particular for use in aircraft as part of the aircraft air-conditioning system. The climate tube 10 , which has according to FIG. 1A an oval-cylindrical cross section and according to FIG. 1B a circular-cylindrical cross section, comprises an inner layer 12 , a honeycomb core 14 and an outer layer 16 . As FIGS. 1A and 1B reveal, the radial extent of the honeycomb core 14 is large compared to the thickness (in radial direction) of the inner layer 12 and the outer layer 16 .
Both the inner layer 12 and the outer layer 16 , which are also referred to as covering layers of the climate tube 10 , are made from a panel-shaped fiber-reinforced composite laminate impregnated with synthetic resin, mostly referred to as a prepreg. Each layer 12 , 16 comprises at least one material ply of the said composite laminate, but may also comprise a plurality of material plies.
The honeycomb core 14 comprises a honeycomb structure likewise impregnated with synthetic resin, for example paper honeycombs impregnated with synthetic resin. Such honeycomb cores are known to experts in the field from sandwich panels that are often used in aircraft construction, in particular for the interior fittings of an aircraft cabin.
The inner layer 12 , the honeycomb core 14 and the outer layer 16 in a finished climate tube 10 are firmly connected to one another, for example by being baked together in a mould (not represented). The climate tube 10 therefore has a homogeneous, continuous sandwich structure, which results in a high stiffness.
From FIG. 2 the structure of a typical embodiment of a climate tube 10 emerges more precisely. The honeycomb core 14 , the individual honeycombs of which are radially aligned, is covered internally by a, here, single-ply layer 12 of fiber composite plastic material and externally by a, here, likewise single-ply layer 16 of fiber composite plastic material. The initially flat honeycomb core 14 is bent into the desired pipe shape, thereby forming two mutually opposed, longitudinally extending abutting edges 18 , 20 . To enable a stable connection of these abutting edges 18 , 20 , the honeycomb core 14 in the region of its abutting edges 18 , 20 is surrounded by a ply 22 of fiber composite plastic material. The inner layer 12 and the outer layer 16 in this case each extend over the ply 22 .
As FIG. 2 reveals, in the region of the abutting edges 18 , 20 a plurality of material plies of the inner layer 12 moreover overlap in order to produce a trouble-free connection in the region of the abutting edges 18 , 20 .
FIG. 3 shows in section a part of a climate tube 10 similar to the one shown in FIG. 1A , wherein for supporting a further climate tube 24 an insert 26 is fastened, for example by means of an adhesive join, in the honeycomb core 14 of the climate tube 10 . By means of a screw 28 screwed into the insert 26 a fixing lug 30 of a clamp-shaped pipe support 32 is fastened to the insert 26 and hence to the climate tube 10 . The further climate tube 24 extends through the pipe support 32 and is in this way supported thereby.
Because of its high proportion of free space formed by the individual honeycombs of the honeycomb core 14 , the honeycomb core 14 has very good temperature-insulating properties. A conventionally required foam material layer, which was applied for insulation purposes onto the exterior of climate tubes, is therefore no longer required.
FIG. 4A shows a further embodiment of a climate tube 10 , in which, in contrast to the embodiment shown in FIG. 3 , an additional pipe 34 is fastened, not by means of special supports to the climate tube 10 , but directly by means of an adhesive join on the exterior of the climate tube 10 . In order to obtain sufficient surface area for a reliable adhesive join and at the same time reduce the dimensions of the total component, the additional pipe 34 is disposed partially embedded in the exterior of the climate tube 10 , i.e. the exterior of the climate tube 10 is provided with an indentation, which receives part of the external peripheral shape of the additional pipe 34 and in which the additional pipe 34 is glued (see in particular FIG. 4B ). The wall thickness of the climate tube 10 is not altered by the provision of the indentation because the layered structure 12 , 14 , 16 forming the wall of the climate tube 10 is pressed inwards in the region of the indentation that receives the additional pipe 34 , with the result that a bulge 36 corresponding to the dimension of the indentation is formed at the inside of the climate tube 10 .
It is evident that in the embodiment shown in FIGS. 4A and 4B a very good positioning of the additional pipe 34 is also achieved, this additional pipe 34 being usable for a variety of purposes, for example to receive electric control lines or to carry a branched-off fluid stream.
FIG. 5 shows a further embodiment of a climate tube 10 having a first additional duct 38 with a small cross section and a second additional duct 40 with a larger cross section. Both additional ducts 38 , 40 extend along the climate tube 10 .
The first, smaller additional duct 38 is formed by a recess 42 in the honeycomb core 14 of the climate tube 10 . The recess 42 may, as represented in FIG. 5 , have an oval cross section, although the cross section may also be rectangular, square or some other shape. The first additional duct 38 formed by the recess 42 is therefore delimited in an inward direction by the inner layer 12 of the air-conditioning tube 10 , at the sides by the honeycomb core 14 and in an outward direction by the outer layer 16 of the climate tube 10 .
The second, larger additional duct 40 , which in the illustrated embodiment is disposed at the opposite side of the climate tube 10 , is based likewise on a, here, larger recess 44 of the honeycomb core 14 , however in this region a recess is additionally formed in the outer layer 16 of the climate tube 10 and in the recess 44 there is fastened, for example by glueing, an insert part 46 , the wall of which in the illustrated example is likewise made of fiber composite plastic material. The insert part 46 has a partial-pipe-shaped cross section, which is fitted by its open side into the recess 44 and fastened therein. The cross section of the second additional duct 40 thus produced is kept relatively flat to minimize the size but may alternatively have a different shape from the one illustrated. The wall of the insert part 46 may also be constructed in an identical manner to the wall of the climate tube 10 , i.e. with a honeycomb core accommodated between two layers.
Both the first additional duct 38 and the second additional duct 40 are usable in many ways. Thus, for example the first additional duct 38 may accommodate control lines, while the second additional duct 40 carries a fluid stream that is separate from the fluid stream carried in the climate tube 10 . These application examples and the size ratios between the individual ducts represented in FIG. 5 are merely by way of example and may easily be modified by the person skilled in the art in accordance with requirements.
Finally, FIG. 6 shows yet a further possible way of providing a climate tube 10 with a plurality of mutually separate ducts. As is evident from FIG. 6 , in the embodiment shown there the free opening cross section of the climate tube 10 is subdivided in longitudinal direction by means of a first dividing wall 48 and a second dividing wall 50 , which both extend in longitudinal direction of the climate tube 10 . The two dividing walls 48 , 50 may, as represented, have a thickness corresponding to the thickness of the wall of the climate tube 10 , and they may also be constructed in an identical manner to the wall of the climate tube 10 , i.e. comprise two outer layers of fiber composite plastic material, between which a honeycomb core is situated. Alternatively, it is possible to form the dividing walls 48 , 50 merely by means of one wall of fiber composite plastic material. In any case, the two dividing walls 48 , 50 produce in the interior of the climate tube 10 three parallel-running chambers 52 , 54 and 56 , the free cross section of which is determined by the position of the dividing walls 48 , 50 and may be varied according to the given requirements. The intended use of the three chambers 52 , 54 and 56 is freely definable, i.e. not all three chambers 52 , 54 and 56 need be used to carry fluid, rather for example the chamber 56 may be used to accommodate electric lines. | A climate tube, in particular for aircraft, includes an inner layer and an outer layer of fiber composite plastic material. To achieve a high stiffness combined with a low weight and to achieve good thermal insulation properties, disposed between the inner layer and the outer layer is an at least almost completely circumferential honeycomb core, which is firmly connected to the inner layer the outer layer. The radial extent of the honeycomb core is large compared to the radial extent of the inner layer and the outer layer, and the mutually opposed longitudinal ends of the honeycomb core abut one another and are surrounded by a ply of fiber composite plastic material. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is based upon and claims priority on U.S. Provisional Application No. 61/517,448, filed on Apr. 19, 2011, the contents of which are fully incorporated herein by reference.
BACKGROUND
Biocontainers are flexible containers which are used for the storage and transport of solutions used in the pharmaceutical industry, as well as for the growth of cells. Solutions that may be carried in a biocontainer include bio-pharmaceutical processed fluids, cultured media, buffer solutions, and active pharmaceutical ingredients. Typically, biocontainers are formed from flexible film materials. Fittings and tubing are used to allow for the ingress and egress of fluids in and out of the biocontainer.
For shipping, a biocontainer is placed in a rigid outer container and filled with the fluid to be carried. The a rigid outer container often is collapsible and is sometimes referred to in the industry as a Reusable Intermediate Bulk Container (rIBC). In some instances, the biocontainer is pre-filled with the fluid and then placed in the rigid outer container. The biocontainer is placed in the rigid outer container with its tubing being accessible, as for example from the top. A foam covering (i.e., a foam dunnage) designed to fit in the rigid outer container is fitted over the biocontainer and has an opening to allow for penetration by the biocontainer tubing. The thickness of the foam is such so as to take up the volume of space not taken up by the biocontainer in the rigid outer container. A lid is then placed over the foam. The lid is pressed down to compress the foam slightly in order to allow for latches on the lid and outer rigid container to engage each other and lock the lid on the outer rigid container. The foam dunnage serves to occupy the space not occupied by the biocontainer and presses against the flexible biocontainer filled with the fluid so as to minimize movement and sloshing of the fluid within the biocontainer. Thus, the size of the foam dunnage required is dependent on the filled size of the biocontainer and the size of the rigid outer container. Moreover, the problem with foam is that it does not adequately support the tubing and thus, the tubing may bend and the fittings may press against the biocontainer wherein the rigid outer container damaging the biocontainer. In addition, while the foam does reduce sloshing and movement of the fluid within the biocontainer, it does not exert sufficient pressure against the biocontainer and as a result the reduction of the sloshing of the fluid within the biocontainer may not be sufficient for preventing premature failures. Consequently, biocontainers still fail prematurely due to cracking caused by such sloshing and movement. Thus, an improved dunnage is desired that would further minimize movement and sloshing and that would support tubing and their fittings so as to reduce premature failures of the biocontainer and tubing.
SUMMARY OF THE INVENTION
In an exemplary embodiment a shipping package for a biocontainer containing a fluid is provided. The package includes a rigid outer container, a flexible biocontainer within the outer container, the biocontainer including at least one of a tubing and a fitting. The package also includes a n inflated dunnage over the biocontainer, the dunnage forming at least an opening penetrated by the at least one of a tubing and fitting, and a lid over the dunnage, wherein the inflated dunnage is sandwiched between the biocontainer and the lid, and wherein the dunnage exerts pressure on the biocontainer and on the lid as well as on at least a wall of the rigid outer container. In one exemplary embodiment, the inflated dunnage engages the at least one of a tubing and a fitting for providing support to the at least one of a tubing and a fitting. In another exemplary embodiment, the lid includes an opening for being penetrated by a port of the inflated dunnage. In yet another exemplary embodiment, a cap is also included for capping the opening on the lid. In a further exemplary embodiment, the dunnage is formed from a film including at least one of a polyamide and polyethylene. In yet a further exemplary embodiment, the inflatable dunnage includes a plurality of chambers. In any of the aforementioned exemplary embodiments, the dunnage is inflated with air.
In another exemplary embodiment, a method for packing a biocontainer for shipping is provided. The biocontainer is placed within a rigid outer container and contains a fluid and includes at least one of a tubing and a fitting. The method includes placing an inflatable dunnage over the biocontainer containing fluid, the dunnage including an opening, and at least one of the at least one of a tubing and a fitting penetrates the opening, placing a lid over the dunnage, and inflating the dunnage. In yet another exemplary embodiment, inflating the dunnage includes inflating the dunnage for exerting a force against the biocontainer, the rigid outer container, and the lid. In a further exemplary embodiment, the lid includes an opening and wherein a dunnage inflating port extends through the opening. In yet a further exemplary embodiment, the method also includes capping the lid opening with a cap. In any of the aforementioned exemplary embodiments, the method also includes partially inflating the dunnage prior to placing the lid. In another exemplary embodiment, partially inflating includes partially inflating the dunnage until the partially inflated dunnage provides support to the at least one a tubing and a fitting. In yet another exemplary embodiment, inflating the dunnage for exerting a force includes inflating the dunnage until the lid starts to bulge. In one exemplary embodiment, the method also includes capping the lid opening with a cap after the inflating the dunnage. In any of the aforementioned exemplary embodiment, the dunnage is inflated to a pressure not greater than 2 psi. In another exemplary embodiment, the inflatable dunnage is formed from a film including at least one of a polyamide and polyethylene. In an exemplary embodiment, the inflated dunnage fills a void between the biocontainer and the lid. In another exemplary embodiment, the dunnage includes a plurality of chambers.
In another exemplary embodiment, an inflatable dunnage for use in transporting biocontainers is provided. The inflatable dunnage includes an inflatable body defining opening for receiving at least one of a tubing and a fitting of a biocontainer, a port for the inlet of air, and a valve coupled to the port for controlling the inlet and outlet of air. In another exemplary embodiment, the body is formed from a film including at least one of a polyamide and a polyethylene. In yet another exemplary embodiment, the inflatable body includes a plurality of chambers.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of an inflatable dunnage of the present invention incorporated over a biocontainer fitted within a rigid outer container.
FIG. 2 is a top view of an exemplary embodiment inflatable dunnage of the present invention.
FIG. 3 is a cross-sectional view of a non-inflated dunnage of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides for an inflatable dunnage 10 that fits over the filled biocontainer 12 in a rigid outer container 14 as shown in FIG. 1 . The inflatable dunnage has at least one opening 16 to allow for penetration by the tubing 18 and fittings of the biocontainer ( FIGS. 1 , 2 and 3 ). In addition, the inflatable dunnage includes its own fitting (i.e., valve) and tubing (or port) 20 (collective the “biocontainer tubing assembly”) to allow for it to be inflated and deflated. In an exemplary embodiment, the inflatable dunnage is formed from a film of polyamide and polyethylene. The film forming the inflatable dunnage in an exemplary embodiment has a gas barrier layer so that it can be stored for a long period of time and not loose pressure because of air permeating through the film material or is made from a material having good gas barrier properties. An exemplary gas barrier material includes Ethylene Vinyl Alcohol (EVOH). Other gas barrier materials that may be used to form the film or a layer attached to the film include, but are not limited to Polypropylene, Nylon, Ethylene Vinyl Acetate. EVOH can be combined with Polyetheylene, polypropylene or Nylon to also form a gas barrier. The combination may occur using lamination or co-extrusion. In one exemplary embodiment, a dual layer film of polyethylene and Nylon is used to form the dunnage.
In an exemplary embodiment, two layers 22 , 24 of film are welded together or otherwise attached to form the inflatable dunnage. In the exemplary embodiment shown in FIG. 2 , the two layers of film 22 , 24 are welded along edges 26 , 28 , 30 , 32 , and along the perimeter 34 of opening 16 to form welded end seams 38 , as for example shown in FIGS. 2 and 3 . In an exemplary embodiment the two layers are also welded along their interior to form at least one interior seam 33 forming segregated chambers 35 as for example shown in FIGS. 2 and 3 . In an exemplary embodiment, the dunnage is placed over the biocontainer in the rigid outer container, and the biocontainer tubing and fittings are pulled through the opening 16 defined through the dunnage. An inflator 17 is then attached to the inflatable dunnage port 20 and to an air source 19 , such as a compressed air source. The inflatable dunnage is then inflated from the air source just enough to take shape and the inflator is disconnected from either the air source or the dunnage fitting/tubing, or both. In an exemplary embodiment, each of the interior seams 33 does not extend to at least one of the end seams 38 . In this regard, the interior of all, the chambers 35 are interconnected such that air entering the port (tubings) 20 will be able to inflate all the chamber 35 . After assuring that all the biocontainer tubing and/or tubing assemblies penetrating the dunnage are stacked in appropriate corners 40 (or proximate the periphery rigid outer container and over the biocontainer), a lid 42 is placed over the inflatable dunnage and the dunnage inflating fitting/tubing penetrates an opening 44 of the lid. The inflator is then attached again to the air source and/or the dunnage fitting/tubing and the dunnage is further inflated until there is a slight bulge on the lid, and the biocontainer tubing assembly penetrating the opening 16 formed through the dunnage is constrained by the dunnage walls 44 defining the opening 16 . A good indicator of a complete fill is when such biocontainer tubing or tubing assembly penetrating the inflatable dunnage is constrained, the lid slightly bulges, and the lid can be slightly compressed by hand. Typically, this would require less than 2 psi of pressure. In an exemplary embodiment, a pressure regulator may also be coupled to the inflatable dunnage to ensure that the appropriate pressure is used to fill the inflatable dunnage. The inflator may then be removed from the inflatable dunnage or tucked away (when disconnected from the air source) through the opening formed on the lid, and a cap is used to cover the lid. Because the compressed air filling the inflatable dunnage is less compressible than foam, and because the inflatable dunnage can be inflated to better fill the void space above the biocontainer, it is capable of applying pressure more evenly against the flexible biocontainer than foam. Consequently, there is less sloshing and movement of the fluid in the biocontainer during shipping than when using a foam dunnage. This results in less wear of the biocontainer, and less cracking and failure of the same. In addition, because the inflated dunnage constrains the biocontainer tubing and/or the fittings of the biocontainer, such tubings and fittings are not damaged during shipping and are not pressed against the biocontainer, thereby preventing damage that is otherwise caused when such fittings are pressed against the biocontainer.
One advantage of the inflatable dunnage of the present invention is that it is much more versatile than standard foam dunnage. For example, a single inflatable dunnage size can be used with multiple fluid volumes biocontainers (i.e., with different size biocontainers) as the inflatable dunnage of the present invention can be filled as necessary for occupying the variable void space between biocontainers and the rigid outer container lids. A fluid filled biocontainer can be filled almost to the top of the rigid outer container or be significantly short of the top and the inflatable dunnage can be designed so that the same inflatable dunnage can be used in both cases. With foam dunnages, on the other hand, different sizes from dunnages would be required for use when shipping biocontainers with varying fill levels.
Applicants believe that more critical than the stiffness of the dunnage is how thoroughly it fills the void space between the biocontainer and the lid. If the pressure is too high, the inflated dunnage will bulge out the lid. With stiffer lids, the dunnage can be filled with more pressure and thus, further press and support to the flexible biocontainer with fluid. However, applicants have discovered that lower pressures, e.g., 2 psi work well also.
The inflatable dunnage of the present invention can be returned to the sender for re-use much more economically because it easily deflates and collapses into a small space. It can be sent back to the sender within the collapsible rigid outer container. With traditional foam dunnage, the polymeric foam forming the dunnage (which is usually a large piece) must be disposed of at the point of product use as it will not fit in a collapsed rigid outer container for return.
Although the present invention has been described and illustrated with respect to exemplary embodiments, it is to be understood that it is not so limited, since changes and modification may be needed which are within the full scope of the invention. For example instead of air, the dunnage of the present invention may be inflated with other gases, including but not limited to Nitrogen, and may also be inflated using other fluids. However, air may be the preferred mode for inflating as it is light in weight and will not add to overall weight of the package including the biocontainer to be used and allows for easy deflation of the dunnage without having to collect it. With fluids such as liquids, there is also the concern for leaks during shipment | An inflatable dunnage for use in transporting biocontainers, a method for packaging a biocontainer with such dunnage and a package including such dunnage and a biocontainer. The inflatable dunnage includes an inflatable body defining opening for receiving at least one of a tubing and a fitting of a biocontainer, a port for the inlet of air, and a valve coupled to the port for controlling the inlet and outlet of air. | 1 |
This is a divisional of copending application(s) Ser. No. 08/200,597 filed on Feb. 23, 1994.
TECHNICAL FIELD
This invention generally relates to an absorbent, flushable, bio-degradable, and medically-safe nonwoven fabric suitable for use as wraps, wipes, absorbent pads, etc., and more particularly, to such fabric formed with polyvinyl alcohol binding fibers.
BACKGROUND ART
In the industry of consumer disposables and medical nonwovens, the emphasis on development is being placed more and more on nonwoven fabrics that are bio-degradable, flushable, without chemicals, and medically safe, possess desired hand (softness) and aesthetic texture, and have sufficient wet strength for their use. Generally, it has been difficult to produce such fabric without using chemicals that may produce reactions in users, or without using mechanical bonding or thermal fusing methods that produce a denser or stiffer fabric or fabric that is not flushable or bio-degradable.
The use of polyvinyl alcohol (PVA) fibers in combination with other absorbent fibers for forming a flushable, bio-degradable nonwoven fabric is known in the industry. The PVA material is known to be medically safe for use in contact with skin or internal body tissues. However, untreated PVA fibers are water soluble and may result in a product that has unacceptably low wet strength. Therefore, prior attempts have used PVA fibers in relatively large amounts of 20% to 90%. However, use of a large amount of PVA fibers results in a product that lacks softness and has a paper-like feel.
Another approach has been to use PVA fibers that have been heat-treated or chemically treated for greater binding strength and stability. For example, in U.S. Pat. No. 4,267,016 to Okazaki, a paper or fabric is formed with PVA fibers that have been treated in a solution of PVA and an adduct of polyamide condensation product and halogen-epoxy propane or ethylene glycol digylcidyl ether in order to render them boiling-water resistant when heat treated. In U.S. Pat. No. 4,639,390 to Shoji, nonwoven fabric is formed with PVA fibers that have been heat-treated and acetalized so as to dissolve in water only at temperatures higher than 100° C. or are insoluble. Although a fabric of increased strength is provided, the use of such treated, insoluble PVA fibers results in a product that is relatively stiff, not satisfactorily flushable or bio-degradable, and/or not medically safe for some users.
SUMMARY OF INVENTION
Accordingly, it is a principal object of the present invention to provide a nonwoven fabric that possesses all of the desired properties of softness, absorbency, flushability, bio-degradability, being medically safe, and having sufficient wet strength for use as wraps, wipes, absorbent pads, etc.
In accordance with the invention, a nonwoven fabric comprises from about 2% up to about 10% of untreated, water-soluble polyvinyl alcohol (PVA) fibers that are heat-bonded to a matrix of absorbent fibers such that said fabric has a wet-to-dry tensile strength ratio of at least 25% in the machine direction (MD) and cross direction (CD), and a drape softness of between 0.5 to 4.0 gmf/gsy in the MD and 0.1 to 0.5 gmf/gsy in the CD.
An especially preferred range for the PVA fibers is from about 4% to about 8% per dry weight of fabric. The use of the low amounts of PVA fibers provides an excellent combination of softness and wet strength. The preferred absorbent fibers are cellulosic fibers such as rayon and cotton. Synthetic fibers such as acetate, polyester, nylon, polypropylene, polyethylene, etc., may also be used.
The invention also encompasses a method for producing nonwoven fabric having PVA binding fibers, comprising the steps of: blending untreated, water-soluble PVA fibers with a matrix of absorbent fibers; carding the blended fibers onto a moving web; adding water to the web in an amount sufficient to soften the PVA fibers for binding to the absorbent fibers while maintaining sufficient web integrity; heating the wetted web in a first stage of heating cylinders in a temperature range of about 40° C. to 80° C. to bind the PVA fibers to the other absorbent fibers; then further heating the web in a second stage of heating cylinders in a temperature range of about 60° C. to 100° C. to complete the binding of the fibers and drying of the web.
The wetting of the web can be accomplished by adding water through a water pickup station then removing excess water from the wetted web through vacuum suctioning. Alternatively, the water can be added in controlled amounts through a padder. The two-stage heating allows the PVA fibers to saturate their bonding points to the other fibers without unduly melting the PVA fibers and weakening them at the lower heating temperature, then completing the thermal binding and drying of the web at the higher heating temperature. The web may also be passed through an aperturing station for low-energy hydroentanglement to enhance the final fabric's strength and texture.
Other objects, features, and advantages of the present invention will become apparent from the following detailed description of the best mode of practising the invention, considered with reference to the drawings, of which:
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 illustrates a process line for producing soft, absorbent, flushable, bio-degradable, medically safe, nonwoven fabric with untreated polyvinyl alcohol (PVA) binding fibers.
FIG. 2 illustrates another version of a process line for producing a desired nonwoven fabric with PVA binding fibers.
FIG. 3 is a photomicrograph depicting the resulting structure of a nonwoven fabric having PVA binding fibers in accordance with the invention.
FIG. 4 is a photomicrograph depicting the resulting structure of a nonwoven fabric having PVA binding fibers that is patterned or apertured by hydroentanglement.
FIG. 5 is a bar chart comparing the PVA fiber percentage amount in the nonwoven fabric compared to weight-normalized machine-direction (MD) dry tensile strength.
FIG. 6 is a bar chart comparing the PVA fiber percentage to MD wet tensile strength.
FIG. 7 is a bar chart comparing the PVA fiber percentage to cross-direction (CD) dry tensile strength.
FIG. 8 is a bar chart comparing the PVA fiber percentage to CD wet tensile strength.
FIG. 9 is a bar chart comparing the PVA fiber percentage to MD dry softness values.
FIG. 10 is a bar chart comparing the PVA fiber percentage to CD dry softness values.
FIG. 11 illustrates the interaction of MD wet tensile strength and softness for rayon/PVA nonwoven fiber.
FIG. 12 illustrates the interaction of CD wet tensile strength and softness for rayon/PVA nonwoven fiber.
FIG. 13 is a bar chart comparing the PVA fiber percentage in apertured nonwoven fabric to MD dry tensile strength.
FIG. 14 is a bar chart comparing the PVA fiber percentage in apertured nonwoven fabric to CD dry tensile strength.
FIG. 15 is a bar chart comparing the PVA fiber percentage in apertured nonwoven fabric to MD wet tensile strength.
FIG. 16 is a bar chart comparing the PVA fiber percentage in apertured nonwoven fabric to CD wet tensile strength.
FIG. 17 is a chart illustrating the interaction between wet strength and dry softness for apertured nonwoven fabric.
DETAILED DESCRIPTION OF INVENTION
Referring to FIG. 1, a process line is schematically shown for producing the nonwoven fabric in accordance with the present invention. First, PVA fibers are blended with other absorbent fibers in a completely homogenized manner using appropriate blending/opening devices (not shown) and then supplied to conventional card units 11 at a carding station 10, with or without the use of scramblers for randomizing the fiber orientation. The carded fibers are transported on a card conveyor 12. A suitable amount of water (hot or cold) is then applied to the web such that the PVA fibers become softened and the web maintains sufficient wet integrity. In the process line shown, the carded web is passed through a pre-wet station 13 which is essentially a flooder wherein water from a tank is applied onto the web. The amount of water applied is controlled using a valve. The pre-wet web with softened PVA fibers is conveyed by a web conveyor 14 through a vacuum module 15 which sucks off excess water from the web, then through a padder station 16 where water from a bath is applied to the web in a controlled amount under a nip roll.
The wet web is then passed through two stages of heating and drying stations wherein it is transported around a series of hot cylinders (steam cans). In the first station 17, the hot cylinders heat the PVA fibers to a temperature in the range of 40° C. to 80° C. in order to soften them so that they adhere to the other absorbent fibers and bind them together, thereby imparting structural integrity and strength to the web. In the second station 18, the web is heated around hot cylinders to a temperature in the range of 60° C. to 100° C. in order to dry the remaining water off and complete the heat-bonding of the fibers. The two-stage heating allows the PVA fiber bonding points to be formed completely without unduly melting the fibers and weakening them. The resulting bonded fabric is then wound up at a winding station 19. The described process is found to produce excellent results for PVA-bonded absorbent fabric such as used in tampons. The following examples demonstrated fabrics suitable for this application.
EXAMPLE 1
Rayon/PVA Blended Fabrics
Using the fabrication process illustrated in FIG. 1, the fiber blend was composed of 95% rayon of 1.5 denier/filament by 40 mm length, obtained from Courtaulds Company in Alabama, USA, sold under the designation Rayon 18453, and 5% PVA fibers of 3.0 denier/filament by 51 mm length, obtained from Kuraray Company in Okayama, Japan, under the designation PVA VPB 201×51. Two card units were used, but the cold water pre-wet flooder was not used. Five sample runs were obtained using straight or scrambled web orientation and at line speeds varying from 45 to 125 feet/minute. The padder used a doctor blade pressure of 40 psi, nip pressure of 40 psi, roll type of 30 cc/yd 2 , and cold water mix. The steam pressure was 20 psi around the first-stage heating cylinders and 40 psi around the second-stage heating cylinders. The fabric had a basis weight of 15 gm/yd 2 , width of 33-34 inches, and thickness of 8 to 11 mils. The fabric properties measured for four sample runs are shown in Table IA.
The tests showed that best results were obtained in Run #4 using a fiber blend of 92% rayon and 8% PVA. This run used scrambling of the fiber orientation on the web and a line speed of 50 feet per minute (fpm). Tensile strength in the machine direction (MD) and the cross direction (CD) was measured by strip test (1"×7" sample) in grams/inch (gm/in). Run #4 had the highest ratio of wet-to-dry tensile strength (33%) and the highest combined measure of wet strength for MD and CD. Run #3 had relatively poor wet strength. The drape softness was measured by the INDA Standard Test Method for Handle-O-Meter Stiffness of Nonwoven Fabrics (IST 90.3-92) in units of gram-force (gmf) per 8.0×8.0 in. 2 test samples (units in Table 1A are converted to gmf/gsy by multiplying by 0.05).
TABLE 1A__________________________________________________________________________ DRY WET DRY WET HOM HOM LINE SPD. TENS MD TENS MD TENS CD TENS CD Soft Soft CDRUN # fpm RAYN/PVA % STRIP gm/in STRIP gm/in STRIP gm/in STRP g/in STRP STRP__________________________________________________________________________ gmf1 Straight web 45 95/5 1371.1 431.3 59.0 18.2 21.0 2.52 Scrambld web 75 95/5 1121.4 340.5 167.9 45.4 24.0 5.03 Straight web 100 95/5 1738.8 213.4 49.9 13.6 21.0 1.94 Scrambld web 50 92.8 1184.9 417.7 222.5 63.6 27.0 5.4__________________________________________________________________________
TABLE 1B__________________________________________________________________________PVA IN BLEND (%) VERSUS NONWOVEN PROPERTIES Rayon/PVA Dry tens MD Wet tens MD Dry tens CD Wet tens CD H-O-M Soft H-O-M Soft CDRUN #Wt. gsy % strip g/in/gsy strip g/in/gsy strip g/in/gsy strip g/in/gsy strip gmf/gsy strip__________________________________________________________________________ gmf/gsy1 11.1 98/2 13.38* 8.29* 0.61* 0.00* 0.93* 0.15*2 11.8 96/4 39.17* 18.53* 2.89* 2.41* 1.99* 0.27*3 15.2 92/8 105.66* 30.44* 11.12* 3.09* 3.66* 0.47*4 12.1 90/10 127.75 41.27 18.20 6.32 4.81 0.695 12.2 84/16 126.31 37.11 19.94 6.03 4.86 0.736 14.2 82/18 136.61 39.97 15.77 6.03 5.45 1.00__________________________________________________________________________
To determine the optimal fiber compositional ranges, tests were conducted using different blends of PVA binding fibers and rayon fibers. For these tests, the product to be optimized was for use as a tampon overwrap. All trials were run at 50 fpm using scrambled web. The same fabrication process as in Example 1 was used, except that no pre-wet flooder or vacuum removal of excess water was used. Instead the web was fed through a padder which controlled the amount of water added to the web.
Table IB shows a summary of the PVA fiber composition of the sample fabrics and their measured physical properties. FIGS. 5-10 are bar charts depicting the tests results comparatively for different measured properties. FIG. 5 illustrates the PVA fiber percentage amount versus weight-normalized MD dry tensile strength, FIG. 6 the PVA fiber percentage versus MD wet tensile strength, FIG. 7 the PVA fiber percentage versus CD dry tensile strength, FIG. 8 the PVA fiber percentage versus CD wet tensile strength, FIG. 9 the PVA fiber percentage versus MD dry softness (handle-o-meter) values, and FIG. 10 the PVA fiber percentage versus CD dry softness values.
The above test results showed that the measured properties were excellent for PVA fiber percentages of 10% or less. The graphs in FIGS. 5-10 confirm that there is no additional value in increasing the PVA fiber percentage greater than 10% as the properties showed no statistically significant improvement. Thus, the boundary for optimal PVA fiber composition was established at 10%. In particular, the overall combination of wet and dry tensile strength and softness (values designated with asteriks) was better for PVA fiber percentages of 2%, 4%, and 8% as compared to percentages of 10% and higher. Optimum properties (adequate strength and softness) for a tampon overwrap were obtained at the 8% PVA fiber level.
FIGS. 11 and 12 illustrate the interaction of the two most important variables to optimize, i.e., wet strength and dry softness. For this comparison, the values were normalized on a fabric weight basis to eliminate the effects of weight variations. The PVA fiber percentages are shown along the X-axis. Weight-normalized wet tensile strength values (gm/in/gsy) are shown along the Y1-axis. The higher the value, the stronger, is the material. The inverse of weight-normalized handle-o-meter values (gsy/gmf) are shown along the Y2-axis. The higher the value, the softer is the material. These charts confirm that the optimal combination of wet strength and softness is obtained at about 8% PVA fiber composition.
EXAMPLE 2
92/8% Rayon/PVA Blend
Further tests were conducted for the optimal rayon/PVA fiber blend, using 92% rayon (1.5 dpf×40 mm, Courtaulds Rayon 18453) with 8% PVA fibers (3.0 dpf×51 mm, Kuraray PVA VPB 201×51). Two card units were used. Two sample runs were obtained using hot water at 60° C. for the padder with and without a lubricity agent obtained from Findley Company, of Wauwatosa, Wis., U.S.A., under the designation L9120. The padder used a doctor blade pressure of 40 psi, nip pressure of 40 psi, and roll type of 30 cc/yd 2 . The line speed was 50 feet/minute. The steam pressure was 20 psi around the first-stage heating cylinders and 40 psi around the second-stage heating cylinders. The fabric had a basis weight of 12 to 15 gm/yd 2 , width of 33-34 inches, and a thickness of 8-9 mils. The fabric properties are summarized in Table II.
The tests showed that the use of a lubricity agent resulted in a significant lowering of wet strength. The wet-to-dry tensile strength ratio was 33% and higher in the first run (without agent), compared to 20% and higher in the second run (with agent).
TABLE II__________________________________________________________________________ DRY WET DRY WETLubricious TENS MD TENS MD TENS CD TENS CD H-O-M Soft MD H-O-M Soft CDRUN #Coatg. STRIP gm/in STRIP gm/in STRIP gm/in STRIP gm/in STRIP gmf STRIP gmf__________________________________________________________________________1 No 1679.8 562.9 181.6 59.9 31.0 7.82 Yes 1543.6 340.5 181.6 49.94 29.0 7.3__________________________________________________________________________
TABLE III__________________________________________________________________________Weight gsy & DRY TENS MD WET TENS MD DRY TENS CD WET TENS FluidRUN #Calipr mils Prodt. Hand GRAB gm/in GRAB gm/in GRAB gm/in GRAB gm/in cap.__________________________________________________________________________ gm/gm1 88 gsy Flexbl 3405.0 1589.0 998.8 544.8 18.280 mil2 94 gsy Flexbl 4040.6 1725.2 3178.0 1407.4 17.672 mil3 96 gsy Stiff 9216.2 3450.4 2360.8 1044.2 15.063 mil__________________________________________________________________________
EXAMPLE 3
Hydroentangled Cotton/PVA Blend
As a process variation, tests were also conducted for hydroentangled nonwoven fabric. The nonwoven web was passed through a patterning/aperturing station for low-energy hydroentanglement on a patterned/apertured support surface to enhance the fabric's strength and texture. The fiber blend used was 92% cotton staple fibers and 8% PVA fibers (3.0 dpf×51 mm). Two card units with scramblers for randomized fiber orientation were used. Three sample runs were obtained at different basis weights between 88-96 gm/yd 2 with and without the doctor blade at the padder. The padder used nip pressure of 40 psi, roll type of 30 cc/yd 2 , and cold water mix. The line speed was 50 feet/minute. The steam pressure was 20 psi around the first-stage heating cylinders and 40 psi around the second-stage heating cylinders. Fluid absorptive capacity was measured in grams of water absorbed per gram of fabric. Strength was measured with a grab test (4"×6" sample). The results are summarized in Table III.
The results showed an increase in CD wet strength using low-energy hydroentanglement (compared to Example 2 above). Wet strength was increased when the fabric was made stiffer. Fluid absorptive capacity was comparable in all runs. Other fluid handling parameters were also measured. The fabric samples showed sink times of 1.6 to 1.8 seconds, wicking in the MD of 3.0 to 3.3 cm/sec, and wicking in the CD of 3.0 to 3.3 cm/sec. The wet-to-dry strength ratio ranged between 33% to 50%.
EXAMPLE 4
Chembond Type Rayon/PVA Blend
The fiber blend used was 92% rayon (1.5 dpf×40 mm) and 8% PVA fibers (3.0 dpf×51 mm). Five sample runs were obtained at different basis weights between 37-75 gm/yd 2 . The tests sought to maximize MD stiffness. Two or three card units (depending on weight) with scramblers, hot water of 100° C. in the flooder, variable padder nip pressure, and variable vacuum pressure were used. The line speed was 50 feet/minute. The steam pressure was 20 psi around the first-stage cylinders and 40 psi around the second-stage cylinders. Fluid absorbent capacity and drape softness/stiffness were also measured. The measured properties are summarized in Table IV.
The test showed that using limited quantities of PVA fiber in the blend and making a "chembond" type fabric allows the manufacture of a product with good strengths and absorption capacity, with enough flexibility to vary the weight, thickness, softness, etc., as desired for different grades of product.
Referring to FIG. 2, a variation of the fabrication process line is shown for handling nonwoven fabric of greater weight and absorbent capacity such as used for baby wipes. The PVA and other fibers are blended completely in a homogenized manner and supplied to (three) card units 21 at a carding station 20 with or without the use of scramblers. The carded fibers are transported on a card conveyor 22. The carded web is passed through a pre-wet station 23 which is essentially a flooder wherein hot or cold water from a tank is applied onto the web controlled using a valve.
The web is passed through an aperturing station 25 using a low energy hydroentangling module. This consists of a perforated rotary drum wherein water jets from manifolds 26, 27, 28 impinge the web at pressure ranging from 50-400 psi. The action of the water jets on the web not only imparts strength through fiber entanglement but also a pattern depending on the pattern of perforations in the aperturing surface. This stage enhances the final fabric's strength and feel/textural aesthetics. A post-aperturing vacuum module 29 is used to suck off excess water from the apertured web, which is important to controlling the hand of the final fabric.
TABLE IV__________________________________________________________________________Wt., gsy and DRY TENS MD DRY TENS CD Drape Stiffness Drape Stiffness FluidRUN #Calpr. mils Prod. Hand GRAB gm/in GRAB gm/in MD STRIP gmf CD STRIP cap.__________________________________________________________________________ gm/gm1 37 gsy Very Stiff 9080.0 3951.0 18.5 11.4 12.618 mils2 37 gsy Very Stiff 11123.0 2814.8 18.4 10.6 12.616 mils3 50 gsy Very Stiff 12848.2 4313.0 18.5 12.5 12.322 mils4 75 gsy Stiff, Bulky & 12666.6 2406.2 14.7 9.4 14.134 mils Softer5 67 gsy Stiff, Bulky & 9488.6 2678.6 17.0 8.3 14.334 mils Softer6 78 gsy Stiff, Bulky & 12258.0 2814.8 17.1 8.3 13.035 mils Softer__________________________________________________________________________
With the desired amount of water present in the web and just enough web integrity, the web is passed through a padder station 30 where water is applied to the web in a controlled amount under a nip roll. The web is then passed through two stages of hot cylinders 31 and 32 for bonding of the fibers and drying. The bonded fabric is wound up at a winding station 33. Examples of apertured rayon/PVA fabric produced in this process line are given below.
EXAMPLE 5
Hydroentangled Rayon/PVA Blend
A first test for apertured nonwoven fabric used a fixed fiber blend of 96% rayon (1.5 dpf×40 mm) and 4% PVA fibers (3.0 dpf by 51 mm). A cold water pre-wet flooder was not used. The manifold pressures at the aperturing station were all 150 psi. The post-aperturing vacuum pressure was -70.0 to -80.0 psi. The doctor blade and nip roller of the padder were not used. The line speed was 50 fpm. The steam pressure was 30 psi around the first-stage cylinders and 40 psi around the second-stage cylinders. Five samples were tested, with Runs #4 and #5 having a top layer of 5 dpf rayon. Drape was measured using the INDA Standard Test for Stiffness (IST 90.1-92) in centimeters of bend (the higher the value, the stiffer the fabric). The measured fabric properties are summarized in Table VA.
TABLE VA__________________________________________________________________________RUN #WGT/THICK DRY STRIP TS WET STRIP TS DRAPE (cms) FLUID CAPAC.__________________________________________________________________________1. 51 gsy MD 2637 gm MD 924 gm MD 13.4 15.0 g/g28 misl CD 250 gm CD 166 gm CD 5.02. 45 gsy MD 3634 gm MD 1198 gm MD 15.8 14.0 g/g23 mils CD 288 gm CD 134 gm CD 4.93. 68 gsy MD 6854 gm MD 2101 gm MD 18.5 13.5 g/g32 mils CD 582 gm CD 244 gm CD 75.04. 61 gsy MD 4192 gm MD 1494 gm MD 15.4 14.1 g/g35 mils CD 441 gm CD 167 gm CD 6.05. 52 gsy MD 4270 gm MD 1187 gm MD 16.2 14.4 g/g29 mils CD 266 gm CD 141 gm CD 4.7__________________________________________________________________________
The test results in Table VA showed wet-to-dry strength ratios ranging between 25% to 40%, relatively soft hand, and good absorptive capacity. Sink times of 2.4 to 3.0 seconds, wicking in the MD of 4.0 to 6.0 cm/sec, and wicking in the CD of 3.7 to 4.9 cm/sec were also measured.
Tests of different rayon/PVA fiber blends were then conducted to determine the optimal fiber compositional ranges, where the product was optimized to be used as a baby wipe. All trials were run at 50 fpm using scrambled web. The same fabrication process for apertured fabric as in the tests for Table VA was used.
Table VB shows a summary of the PVA fiber compositions and their nonwoven properties. FIGS. 13-16 are bar charts depicting the tests results comparatively. FIG. 13 illustrates the PVA fiber percentage amount versus weight-normalized MD dry tensile strength, FIG. 14 the PVA fiber percentage versus CD dry tensile strength, FIG. 15 the PVA fiber percentage versus MD wet tensile strength, and FIG. 16 the PVA fiber percentage versus CD wet tensile strength.
TABLE VB__________________________________________________________________________PVA IN BLEND (%) VERSUS NONWOVEN PROPERTIES Dry tens MD Wet tens MD Dry tens CD Wet tens CDRUN #Wt. gsy Rayon/PVA % strip g/in/gsy strip g/in/gsy strip g/in gsy strip g/in/gsy__________________________________________________________________________1 64.5 98/2 65.2* 27.3 4.3* N/A2 63.4 96/4 66.8* 27.9* 5.5* 4.3*3 71.1 90/10 98.7 33.1 13.1 5.54 72.8 84/16 110.3 33.1 16.2 5.05 69.5 82/18 127.2 38.4 15.4 5.9__________________________________________________________________________
The test results showed that the values for the lower PVA fiber percentages, i.e., 2% and 4% were statistically better than the values obtained for the 10%, 16%, and 18% rayon/PVA blends. There was little additional value in increasing the PVA fiber composition greater than 10% as the resulting properties showed no significant improvement.
FIG. 17 illustrates the interaction of the two important variables to be optimized, i.e., cross directional wet strength and cross directional softness (inverse of dry stiffness). Both values were normalized on a fabric weight basis to eliminate the effects of weight variations. The PVA fiber percentages are shown along the X-axis. Weight-normalized wet tensile strength values (gm/in/gsy) are shown along the Y1-axis. The higher the value, the stronger is the material. The inverse of weight-normalized drape stiffness (gsy/gmf) are shown along the Y2-axis. The higher the value, the softer is the material. The value lines intersect at 8% PVA fiber blend, representing an optimal combination of wet strength and softness.
EXAMPLE 6
Hydroentangled Rayon/PVA Blend
The fiber blend used was 96% rayon (1.5 dpf×40 mm) and 4% PVA fibers (3.0 dpf by 51 mm). A cold water pre-wet flooder was used. The manifold pressures at the aperturing station were 150 and 200 psi. The post-aperturing vacuum pressure was -40.0 psi. The doctor blade and nip roller of the padder were not used. The line speed was 50 fpm. The steam pressure was 20 psi around the first-stage cylinders and 40 psi around the second-stage cylinders.
Different weights and thicknesses of fabric were tested, and the measurements for the resulting properties are summarized in Table VI. The test results showed wet-to-dry strength ratios ranging between 20% to 50%, good softness values, and high fluid absorption capacities.
In summary, nonwoven fabrics having low amounts of PVA fibers bonded to other absorbent fibers such as rayon and cotton are found to have sufficient wet strength and good hand and softness along with excellent fluid handling and absorption properties. These nonwoven fabrics are highly suitable for use in tampons, diapers, sanitary napkins, wipes, and medical products. The fluid holding capacity can be increased when superabsorbent fibers are introduced in the matrix and bonded together with the PVA fibers. Hence, these fabrics also find ideal use as an absorptive core material.
The proportion of PVA fibers in the matrix can be varied depending on the denier and staple length employed. PVA fiber blends of from about 2% up to about 10% are found to provide the required wet strength and softness properties desired for the applications mentioned above. These low amounts provide a wet-to-dry tensile strength ratio of at least 25% in the machine direction (MD) and in the cross direction (CD), drape softness of between 0.5 to 4.0 gmf/gsy in the MD and 0.1 to 0.5 gmf/gsy in the CD. Apertured nonwoven fabric having the PVA binding have high fluid absorptive capacities of between 8 and 20 grams of water per gram of fabric. More than 10% of PVA fibers does not provide an appreciable increase in strength but has increased stiffness, which is a deterrent to use in many of the applications mentioned. Softness and wet strength are the principal combination of properties desired.
TABLE VI______________________________________PROPERTIES Roll #1 Roll #2 Roll #3 Roll #4______________________________________Weight/ThicknessWeight, gsy 67.7 65.3 69.6 69.0Thickness, mils 33.0 31.0 33.1 33.0DRY-STRIP TENSILEMD Tensile, gms 5436.0 4617.0 6541.0 6212.0CD Tensile, gms 539.1 408.5 628.0 729.4MD Elongation, % 9.8 10.5 9.3 9.7CD Elongation, % 41.0 38.8 30.8 38.0WET-STRIP (H.sub.2 O)MD Tensile, gms 1577.0 1588.0 2053.0 2150.0CD Tensile, gms 227.4 178.5 259.1 259.3MD Elongation, % 24.4 26.7 23.2 24.1CD Elongation, % 115.5 89.3 103.6 95.7DRY-GRAB TENSILEMD Tensile, gms 8762.2 7536.4 10396.6 9761.0CD Tensile, gms 2270.0 1816.0 2996.4 2542.4MD Elongation, % 12.0 12.6 10.5 10.8CD Elongation, % 53.0 53.0 49.3 49.7WET-GRAB (H.sub.2 O)MD Tensile, gms 3132.6 2905.6 3541.2 3541.2CD Tensile, gms 1089.6 1225.8 1316.6 1180.4MD Elongation, % 34.9 36.1 32.4 32.8CD Elongation, % 170.5 182.6 162.2 154.0DRY-STRIP TOUGH.MD Tough., gm/in.sup.2 451.5 395.3 488.0 473.6CD Tough., gm/in.sup.2 190.6 144.5 170.1 215.1WET-STRIP (H.sub.2 O)MD Tough., gm/in.sup.2 337.0 377.7 397.6 425.4CD Tough., gm/in.sup.2 163.5 116.5 178.2 166.7DRY-GRAB TOUGH.MD Tough., gm/in.sup.2 280.2 311.6 368.2 311.6CD Tough., gm/in.sup.2 312.0 235.0 373.5 331.8WET-GRAB (H.sub.2 O)MD Tough., gm/in.sup.2 397.0 361.0 379.6 425.4CD Tough., gm/in.sup.2 337.0 371.3 381.2 166.7STIFFNESSMD Drape, cms 16.9 15.2 18.5 18.5CD Drape, cms 6.8 5.1 7.6 8.9ABSORPTIONSink time, secs 1.44 1.43 1.78 1.7Capacity, gm/gm 13.0 12.6 12.0 12.2______________________________________PROPERTIES Roll #5 Roll #6 Roll #7 Roll #8______________________________________Weight/ThicknessWeight, gsy 63.8 64.4 59.7 62.5Thickness, mils 32.8 31.1 29.2 30.0DRY-STRIP TENSILEMD Tensile, gms 4173.0 4504.4 4012.0 4327.0CD Tensile, gms 452.8 125.4 396.2 382.9MD Elongation, % 10.4 9.6 11.2 11.1CD Elongation, % 41.5 41.6 48.7 38.4WET-STRIP (H.sub.2 O)MD Tensile, gms 1452.0 1390.0 1564.0 1409.0CD Tensile, gms 245.0 81.2 203.0 238.1MD Elongation, % 26.2 25.7 26.8 26.7CD Elongation, % 115.3 116.7 107.4 110.5DRY-GRAB TENSILEMD Tensile, gms 7854.2 7536.4 7491.0 7536.4CD Tensile, gms 1997.6 1634.4 1816.0 1725.2MD Elongation, % 12.6 12.5 13.0 12.6CD Elongation, % 63.1 78.5 77.5 63.6WET-GRAB (H.sub.2 O)MD Tensile, gms 2769.4 2724.0 2814.8 2724.0CD Tensile, gms 1316.6 1135.0 1362.0 1271.2MD Elongation, % 42.1 40.2 39.6 37.1CD Elongation, % 200.0 194.2 199.3 194.6DRY-STRIP TOUGH.MD Tough., gm/in.sup.2 347.6 384.5 372.0 391.2CD Tough., gm/in.sup.2 176.4 45.8 164.4 124.1WET-STRIP (H.sub.2 O)MD Tough., gm/in.sup.2 332.0 367.7 367.6 353.3CD Tough., gm/in.sup.2 179.7 57.8 135.1 161.2DRY-GRAB TOUGH.MD Tough., gm/in.sup.2 274.0 307.5 272.4 281.1CD Tough., gm/in.sup.2 309.0 302.0 316.8 279.3WET-GRAB (H.sub.2 O)MD Tough., gm/in.sup.2 333.7 373.4 414.6 356.0CD Tough., gm/in.sup.2 446.4 361.2 428.4 420.4STIFFNESSMD Drape, cms 13.7 15.2 15.0 15.9CD Drape, cms 5.9 6.5 6.5 6.8ABSORPTIONSink time, secs 1.66 1.62 1.65 1.54Capacity, gm/gm 12.8 12.7 12.5 12.6______________________________________PROPERTIES Roll #9 Roll #10 Roll #11 Roll #12______________________________________Weight/ThicknessWeight, gsy 64.0 68.4 64.5 70.5Thickness, mils 30.5 34.2 31.7 34.8DRY-STRIP TENSILEMD Tensile, gms 4512.0 5048.0 5193.0 6112.0CD Tensile, gms 148.1 173.4 221.8 268.1MD Elongation, % 9.2 9.7 8.7 9.2CD Elongation, % 35.6 36.6 40.3 34.4WET-STRIP (H.sub.2 O)MD Tensile, gms 1638.0 1433.0 1746.0 2154.0CD Tensile, gms 231.6 244.7 118.5 298.7MD Elongation, % 24.6 26.6 24.8 23.8CD Elongation, % 118.0 115.0 121.3 115.1DRY-GRAB TENSILEMD Tensile, gms 7808.8 8081.2 9307.0 10896.CD Tensile, gms 1997.6 1997.6 2542.4 2860.2MD Elongation, % 12.6 12.4 12.0 12.3CD Elongation, % 74.8 63.8 55.5 51.1WET-GRAB (H.sub.2 O)MD Tensile, gms 2678.6 3041.8 3087.2 3405.0CD Tensile, gms 1225.8 1089.6 1362.0 1362.0MD Elongation, % 35.6 39.9 33.3 30.0CD Elongation, % 184.7 166.2 185.0 169.7DRY-STRIP TOUGH.MD Tough., gm/in.sup.2 340.3 377.5 384.5 442.1CD Tough., gm/in.sup.2 45.6 56.8 72.6 79.0WET-STRIP (H.sub.2 O)MD Tough., gm/in.sup.2 366.3 359.6 402.0 439.6CD Tough., gm/in.sup.2 165.0 178.0 86.2 216.4DRY-GRAB TOUGH.MD Tough., gm/in.sup.2 269.5 333.9 331.3 397.7CD Tough., gm/in.sup.2 358.2 310.7 381.5 368.4WET-GRAB (H.sub.2 O)MD Tough., gm/in.sup.2 334.8 376.6 348.4 464.9CD Tough., gm/in.sup.2 382.4 356.5 400.1 434.9STIFFNESSMD Drape, cms 16.5 18.3 18.4 18.6CD Drape, cms 5.5 7.3 6.7 7.8ABSORPTIONSink time, secs 1.63 1.77 1.62 1.63Capacity, gm/gm 12.5 12.6 12.2 12.3______________________________________
Although the above examples use cotton and rayon matrix fibers, the PVA binding fibers can also be used with synthetic fibers such as acetate, polyester, polypropylene, polyethylene, nylon, etc. They may also be used with other types of fibers to form higher strength and/or denser nonwoven fabrics such as spunbond, spunlaced, and thermally bonded nonwovens, in order to obtain superior hydrophilic and oleophilic wipes.
Numerous modifications and variations are of course possible given the above disclosure of the principles and best mode of carrying out the invention. It is intended that all such modifications and variations be included within the spirit and scope of the invention, as defined in the following claims. | An absorbent, flushable, bio-degradable, and medically-safe nonwoven fabric suitable for use as wraps, wipes, absorbent pads, etc., is composed of from 2% to 10% by weight of untreated, water-soluble polyvinyl alcohol (PVA) fibers that are heat-bonded to a matrix of absorbent fibers. The use of PVA fibers in low amounts provides softness, while sufficient wet strength is provided by heat bonding the PVA fibers completely to the other fibers in a two-stage heating process. The resulting nonwoven fabric has a high wet-to-dry tensile strength ratio, good drape softness, and high fluid absorptive capacity. In a method for producing the nonwoven fabric, the PVA fibers are blended with the absorbent fibers, the blended fibers are carded onto a moving web, sufficient water is added to wet the PVA fibers while maintaining web integrity, then the web is heated in two stages, the first with heating cylinders at 40° C. to 80° C., then the second with heating cylinders of 60° C. to 100° C. The fiber web may also be hydroentangled and patterned for enhanced strength and textural properties. | 3 |
ORIGIN OF THE INVENTION
The invention described herein was made by employees of the United States Government and may be manufactured and used by or for the Government for governmental purposes without the payment of any royalties thereon or therefor.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to the processing and storing of holographic images and, more particularly, to a method and apparatus for dynamically storing a holographic image by oscillating between two photorefractive crystals in which interference patterns are created by four-wave mixing.
2. Description of the Related Art
Holographic images have been created, stored and manipulated in many different ways for many different purposes. Typically, a holographic image is formed using a laser, most often operating in the visible light spectrum and less often in the X-ray region or other wavelengths of electromagnetic radiation. In the following description of the prior art and the invention, the word "processing" will ordinarily be used to refer to both storage, with or without modification, and manipulation of a holographic image by, e.g., amplification, Fourier transformation, enhancement, etc. Many different types of optical elements have been used to perform such processing on laser beams carrying amplitude/phase information which will hereafter be referred to as a holographic image.
One type of optical element used to perform such processing includes a photorefractive crystal which can perform filtering and image storing functions. Such crystals may be formed of bismuth silicone oxide, barium titanate and related materials. Such crystals have been used in systems for enhancement of optical features, as taught by U.S. Pat. No. 4,674,824, to form a double phase-conjugate mirror used for image processing, interferometry and rotation sensing taught in an article by Weiss et al. in Optics Letters, Volume 12, No. 2, pages 114-116 and in a self-oscillator, as taught by Huignard et al. in Proceedings of SPIE, volume 613, pages 22-31. However, none of these systems are capable of indefinitely storing a holographic image after the original object beam discontinues to be supplied.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method of storing a holographic image without continuously supplying the original object beam.
Another object of the present invention is to provide a method for dynamically storing the holographic image using oscillation between two photorefractive crystals.
The above objects are attained by a method of storing a holographic image, comprising the steps of: receiving an object beam and first and second sets of reference beams; creating a first dynamic interference pattern between the object beam and the first set of reference beams to produce a phase-conjugate object beam; creating a second dynamic interference pattern between the phase-conjugate object beam and the second set of reference beams to produce a reconstructed object beam; and directing the reconstructed object beam into the first dynamic interference pattern to enable continuance of the first and second dynamic interference patterns after the object beam is no longer received. The dynamic interference patterns are formed due to four-wave mixing of two of the three incident beams, while the third is used to "read" the holographic image. Preferably, the first and second interference patterns are formed in first and second photorefractive crystal regions. These regions may be in separate crystals or different regions of the same crystal.
These objects, together with other objects and advantages which will be subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like reference numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of information flow in an apparatus according to the present invention; and
FIG. 2 is a block diagram of an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
According to the present invention, amplitude and phase information forming a holographic image supplied in an object beam I 3 is directed towards a first photorefractive crystal 10. A first interference pattern forms a hologram in the crystal 10 when the object beam I 3 meets a first set of reference beams I 1 and I 2 . Reference beam I 1 will be referred to as a write beam and reference beam I 2 will be referred to as a read beam although it is also known as a pump beam. The write and read beams I 1 and I 2 are counter-propagating, i.e., directed in opposite directions as illustrated in FIG. 1.
The angular relationships between the first set of reference beams I 1 , I 2 and the object beam I 3 is such that a phase-conjugate object beam I 4 is produced by crystal 10, colinear with the object beam I 3 and propagating in an opposite direction. The read and write beams I 1 , I 2 must be colinear to produce beam I 4 as a phase-conjugate beam. The Optics 12 are provided for directing the phase-conjugate object beam I 4 towards a second photorefractive crystal 14. The optics 12 may also perform other functions as discussed below.
The phase-conjugate object beam I 4 , together with a second set of reference beams I 5 and I 6 form a second dynamic interference pattern in crystal 14. The second set of reference beams I 5 and I 6 consist of a write beam I 5 and a read beam I 6 . In a manner similar to that in crystal 10, the beams I 4 , I 5 and I 6 produce a phase conjugate of the phase-conjugate object beam I 4 . This resulting beam I 3 ' is a reconstructed object beam which is counter-propagating with respect to the phase-conjugate object beam I 4 . The optics 12 provide means for directing the reconstructed and phase-conjugate object beams I 3 ' and I 4 toward crystals 10 and 14, respectively. As a result, an oscillation is set up between crystals 10 and 14 which permit a switch 16 to be opened, discontinuing the supply of the object beam I 3 , while the first and second dynamic interference patterns are maintained.
The first and second interference patterns can be maintained due to certain properties of photorefractive crystals and the relative intensities and angular relationships between the light beams incident on the crystals 10 and 14. The hologram which constitutes the first dynamic interference pattern is formed by four-wave mixing of two coherent light beams I 1 , I 3 and read beam I 2 which may or may not be coherent with respect to light beams I 1 and I 3 . The mixing of these two beams in the first photorefractive crystal region 10 creates a phase grating within the crystal 10 which diffracts a portion of the write and read beams I 1 and I 2 . This diffracted beam exits the crystal as the phase-conjugate object beam I 4 . A similar phase grating is created in the second photorefractive crystal region 14 by the phase-conjugate object beam I 4 , write beam I 5 and read beam I 6 .
The mechanism by which the phase grating is produced in the photorefractive crystal regions is as follows. The write (reference) and object (phase-conjugate object or reconstructed object) beams will interfere because they are coherent. The resulting interference pattern produced by the addition of these two beams, that is, the spatial variations in light intensity which characterize the interference pattern, cause charge carriers within the crystal regions 10 and 14 to migrate. Charges which are created in regions of high light intensity move to regions of low light intensity. This charge migration effect may be accelerated by application of an external electric field across the crystal. After a period of time which depends upon the intensity of the incident light, magnitude and direction of the applied external field and properties of the photorefractive crystal, an equilibrium state is reached within the crystal. At equilibrium, a space charge distribution exists within the crystal which gives rise to a spatially varying electrostatic field. This electrostatic field induces a change in the index of refraction by the electro-optic effect. The spatially varying index of refraction is the phase grating which produces diffraction of the three beams.
Typically, the reference beams I 1 , I 2 each have an intensity which is much greater than the intensity of the object beam I 3 . There will usually be a difference in the intensity of the reference beams, such that the ratio I 2 I 1 is greater than one. The reflectivity R of the crystal is defined as indicated in equation (1). ##EQU1## The diffraction efficiency μ is always less than one and at best is typically around 0.5. The diffraction efficiency μ can be varied by changing the orientation of the beams I 1 , I 2 , I 3 with respect to the optical axis of the crystal 10.
Thus, it is possible to amplify the object (phase-conjugate object or reconstructed object) beams by varying the angle between the optical axis of the crystal and the incident read and object beams or by varying the ratio of the intensity of the read and write beams, as well as by applying an electric field along the optical axis of the crystal 10 or 14. By changing the angles of the three beams I 1 , I 2 and I 3 (or I 4 , I 5 and I 6 ) respective to the optical axis of the crystal, energy from the read beam I 2 may be diffracted into the phase-conjugate object beam I 4 (or I 6 into I 3 '). Because it is possible to amplify the object beam each time it is mixed with the read and write beams, attenuation of the signal as it passes through optics 12 does not prevent indefinite continuance of the interference patterns in the crystals 10, 14, provided the reference beams I 1 , I 2 , I 5 and I 6 are continuously supplied.
In addition to producing sufficient gain in one of the two crystals 10 and 14 so that the image does not degrade, oscillation of the holographic image requires that the phase of the phase-conjugate object beam I 4 and the reconstructed object beam I 3 ' must be in a specific relationship. The overall round-trip phase from crystal 10 to crystal 14 and back to crystal 10 must be an integral multiple of 2π. The existence of this condition is determined by the coupling coefficient, the length of the crystals and the time constant of the system. Basically, the time constant for substantially identical crystals will be roughly equal if the total light intensity incident on the crystals 10, 14 is the same, because the time constant is inversely proportional to the total light intensity.
Any material which exhibits photoconductivity or a photovoltaic operation can be used for the photorefractive crystals 10 and 14. Examples of such crystals include Bi 12 SiO 20 , Bi 12 GeO 20 , BaTiO 3 , etc., which are sensitive to light in the visible region of the electromagnetic spectrum, and semiconductor materials such as gallium arsenide and silicon which are sensitive to light in the infrared region of the electromagnetic spectrum. Other materials may be used which are sensitive to other regions of the electromagnetic spectrum, such as X-rays. Thus, a wide range of materials and wavelengths of beams may be used in constructing this invention.
As noted above, the two crystal regions 10 and 14 may be different regions of the same crystal. On the other hand, they may be two separate crystals and may even be made of different materials. Specific dimensions of the crystals and angular arrangements of the light beams are unimportant as long as coherence is maintained between beams I 1 , I 3 and I 3 ' and between I 4 and I 5 . The frequency of the beams must be matched to the characteristics of the crystals, but as noted above, any of a wide range of frequencies may be selected, depending upon the properties of the crystal chosen. Thus, the read and write beams in a single crystal do not have to be in coherence and possibly may be permitted to have slightly different frequencies, but the read beam in one crystal will have to be in coherence with the write beam in the other crystal.
The optics 12 through which the phase-conjugate object beam I 4 and reconstructed object beam I 3 ' pass may be formed of many different types of optical elements, such as lenses, spatial filters (masks), etc. As noted above, the controllable amplification in one or both of the crystal regions 10 and 14 can compensate for a significant amount of loss in the optics 12 without affecting the ability of the interference patterns to be maintained in the crystals 10 and 14. The amplification which occurs in the crystals may be accomplished in many different ways, including controlling the intensity of at least one beam in the first and second sets of reference beams, or the angular relationships between the objects and reference beams in at least one of the crystals.
An embodiment of the invention indicating one way of controlling the amplification in one of the crystals is illustrated in FIG. 2. All of the light beams used in the apparatus illustrated in FIG. 2 are supplied by a laser 20. In the embodiment illustrated in FIG. 2, two separate refractive crystals 10 and 14 are used. As noted above, BaTiO 3 crystals may be used with light beams in the visible spectrum. Thus, the laser 20 may be an argon or helium-neon laser. While the power of the laser 20 depends upon the amount of loss in the system and the physical size of the system, a He-Ne laser with a power of 35 mW has been used to successfully create an oscillation between two BaTiO 3 crystals.
The light emitted by the laser 20 is separated into two beams by a beam splitter 22, such as optical glass coated with a metallic reflector with a transmission efficiency of 50%. One of the beams created by the beam splitter 22 is reflected by a mirror 28, passes through an electronic shutter 30 and object beam generation means 32. The object beam generation means 32 may include many different types of optical elements. In the illustrated embodiment, the elements include a pinhole 34, lenses 35, 36 and mask 38. The mask 38 may be a slide containing an image, including an integrated circuit mask as in the apparatus disclosed in U.S. Pat. No. 4,674,824. Alternatively, the source of the object beam may be derived from sources other than a mask. Furthermore, the object beam creation means 32 may contain any elements conventionally used to produce a holographic image.
The other beam generated by the beam splitter 22 is used to produce the reference beams. This beam passes through beam splitters 41, 42 to create three beams. The beam splitters 41 and 42 may be similar to beam splitter 22. One of the beams generated by beam splitter 41 is used to produce the write beam I 1 and thus is directed towards the first crystal 10. Preferably, this beam I 1 is of much lower intensity than the beam which is directed towards beam splitter 42. As a result, beam splitter 42 is able to generate two beams I 2 ', I 5 , one I 2 ' of which is directed towards a variable attenuator 44. This beam I 2 ' preferably has a significantly higher intensity than the write beam I 1 . After passing through the variable attenuator 44 and reflecting off of mirrors 46, 47 this beam becomes the read beam I 2 . The other beam I 5 generated by the beam splitter 42 is reflected by mirrors 49, 50 and directed towards the second crystal 14 as the write beam I 5 . After passing through the crystal 14, this beam is reflected by mirror 52 and thus becomes the read beam I 6 .
Thus, only a single variable attenuator 44 is required to provide beam intensity control means for controlling the intensity of at least one of the read and write beams. Alternatively, additional means for controlling intensity of other reference beams may be provided. For example, liquid crystal gates may be used to modify beam intensity and spatial distribution of the light beams. In addition to using multiple liquid crystal gates, additional variable attenuators may be used on any of the read and write beams I 1 , I 2 , I 5 and I 6 . Any of these variable attenuators, including variable attenuator 44, may be a pockel cell, a set of linear filters, or any element capable of providing variable attenuation of light intensity, including modulation of beam amplitude. In addition, instead of using a reflection of the write beam I 5 to produce the read beam I 6 , the read beam I 6 may be generated by, e.g., replacing mirror 49 with a beam splitter which directs one of the beams towards mirror 52. Also, it should be understood that the mirrors 49, 50 are arranged in three-dimensional space in such a manner that there is no interference with the object beam generation means 32. As illustrated in FIG. 2, the object beam I 3 is created after passing through a beam splitter 54. This beam splitter is part of the optics 12 illustrated in FIG. 1, although for simplicity the object beam I 3 is not illustrated as passing through the optics 12. The phase-conjugate object beam I 4 , after some loss in intensity, is directed by the beam splitter 54 through lenses 56, 57 and beam splitter 60 towards the second crystal 14. The lenses 56, 57 and beam splitter 60 are also included in the optics 12 illustrated in FIG. 1. The phase-conjugate object beam I 4 and write and read beams I 5 and I 6 form the reconstructed object beam I 3 ' in the second crystal 14 as described above. The beam splitter 60 provides output means for outputting at least one of the phase-conjugate and reconstructed object beams I 3 ' and I 4 . A camera detector or other image detecting device 62 receives the output beam. Alternatively, the output beam can be supplied as a new object beam to a holographic storage apparatus similar to that illustrated in FIG. 2. Coupling several such apparatuses with variations in spatial filters, optical switches and lenses enables the creation of an extensive optical processor or computing system. Thus, the phase-conjugate object beam or reconstructed object beam can be used in extensive processing.
As illustrated in FIG. 2, the beam splitter 54 directs a portion of the reconstructed object beam I 4 towards a photomultiplier tube detector 64 which comprises a sensor for control means 66, 67 for controlling the variable attenuator 44. The control means 66, 67 may comprise a delay unit 66 and voltage supply 67. Where it is desired to maintain stable oscillation between the photorefractive crystals 10 and 14 after the electronic shutter 30 closes, effectively opening switch 16 (FIG. 1), the control means 66, 67 can control the attenuation of the light beam passing therethrough in response to the light intensity detected by photomultiplier tube 64.
If it is desired to process the holographic image by, e.g., amplification, the control means can be adjusted to perform this operation. Additional operator control (not shown) or other input means can be provided to determine how the control means 66, 67 varies the attenuation of variable attenuator 44. In a simple system, the control means 66, 67 may be replaced by manual manipulation of, e.g., a set of linear filters forming the variable attenuator 44, to control the gain in crystal 10. In this case, the intensity of the light beams I 1 -I 6 and the responsiveness of the crystals 10, 14 to the frequency of the light beam must be selected to provide sufficiently slow response, on the order of a fraction of a hertz to enable manual manipulation of a filter to control the oscillation between the crystals 10, 14. On the other hand, known photorefractive crystals have a sufficiently high responsiveness to conventional lasers to produce oscillations on the order of kilohertz. Thus, the present invention is capable of high speed processing of optical images enabling the construction of a high speed optical processor.
The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope and spirit of the invention as recited in the appended claims. | A real-time dynamic holographic image storage device uses four-wave mixing in a pair of photorefractive crystals. An oscillation is produced between the crystals which can be maintained indefinitely after the initial object beam is discontinued. The object beam produces an interference pat
ORIGIN OF THE INVENTION
The invention described herein was made by employees of the United States Government and may be manufactured and used by or for the Government for governmental purposes without the payment of any royalties thereon or therefor. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to cold-formed machine bolts and, in particular, methods and tooling for economically producing such machine bolts.
PRIOR ART
Machine bolts are commonly made by producing a headed blank or preform in a progressive cold-forming or forging machine and, thereafter, rolling a thread on the shank of the blank. Typically, the shank end of the blank is chamfered so that when finished, the threaded bolt has a “point”, albeit blunt, that enables it to be self-centering with a threaded hole and thereby facilitate its final assembly.
Conventionally, the cold-forming process can involve five progressive forming stations. Typically, the tooling for shaping at least the shank part of the blanks is dependent on the length of a bolt. Thus, the prior art number of forming stations and the use of length specific tooling makes the tooling for a full range of bolt lengths relatively expensive for a bolt manufacturer. Consequently, to limit tooling costs, it is not unusual for a manufacturer to produce only a limited number of bolt lengths for a given bolt size (diameter). As a result, the manufacturer may not achieve the greatest economy and a bolt distributor or high volume user may have to depend on more than one manufacturer to supply its needs. Frequently, the cold-forming tooling available to a manufacturer may be incapable of pointing the blank so that a second machining operation is required and attendant material, machine time and labor costs are incurred.
SUMMARY OF THE INVENTION
The invention provides an exceptionally versatile tooling package for progressive forming machines capable of producing blanks for a full range of bolt lengths, all pointed, in four die stations. The number of tools or dies is greatly reduced compared to prior art practices, and can be applied to a four station header to produce a full range of pointed bolt lengths. This feat, which greatly reduces the number of tools, is accomplished in part by use of different fillers and/or a multi-position blank head supporting sleeve to axially position a tool or tools each at an appropriate one of multiple locations and thereby account for different blank lengths. More specifically, a complete set of forming tools can comprise a progressive series of cavities for forming and supporting the blank head and groups of tools for shaping the shanks of threaded to the head blanks or blanks with partially threaded shanks.
The ability to use a four station machine, as afforded by the invention, rather than a five station machine, represents a significant reduction in tooling. Moreover, the disclosed methodology permits the use of some of the same tools to make hex flange bolts, hex head bolts, and socket head cap screws, thereby affording significant additional savings in tooling costs.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view taken in a horizontal plane of a four station progressive cold-forging machine set up to make short threaded to the head hex flange bolts;
FIG. 2 is a cross-sectional view taken in a horizontal plane of a four station progressive cold-forging machine set up to make long partially threaded hex flange bolts;
FIG. 3 is a is a cross-sectional view taken in a horizontal plane of a four station progressive cold-forging machine set up to make full thread hex head bolts;
FIG. 4 is a cross-sectional view taken in a horizontal plane of a four station progressive cold-forging machine set up to make partially threaded hex head bolts;
FIG. 5 is a cross-sectional view taken in a horizontal plane of a four station progressive cold-forging machine set up to make short threaded to the head socket head cap screws;
FIGS. 6 a - i are a series of partial sections of the third station of the forging machine set up to point blanks of different lengths in the process shown in FIG. 2 ;
FIG. 7 is an exploded perspective view of a multi-position bolt head supporting sleeve and associated case and keys of the invention;
FIG. 8 is a fragmentary cross-sectional view of the fourth station of the machine depicted in FIG. 1 , taken in a vertical plane, set up for pointing relatively short, threaded to the head hex flange head bolts;
FIG. 9 is a view similar to FIG. 8 showing a set up for extruding the roll diameter of relatively long partially threaded hex flange head bolts; and
FIG. 10 is an exploded perspective view of a hard plate and case assembly constructed in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A cold forging machine 10 of generally conventional construction is represented by a die breast 11 and a slide 12 in FIGS. 1-5 . The illustrated machine 10 has and the disclosed bolt forming processes uses four part forming or work stations 13 - 16 . In FIGS. 1-5 , the slide or ram 12 is shown in its forwardmost position where the opposed faces of the punch and die cases can be as close as 1 mm.
As mentioned above and explained in greater detail below, the invention offers a methodology for forming several popular styles of bolts in standard lengths, pointed and ready to be roll threaded, with a greatly reduced number of tools compared to that of previously used conventional methods. It will be understood that the tooling and process disclosed herein produce pointed bolt preforms or blanks that are subsequently finished in thread rolling dies, known in the art. These bolt preforms or blanks, as is customary in the industry, are sometimes simply called bolts herein, and this term is likewise applied herein to the parts being progressively formed.
In the following written disclosure and drawings, like parts are identified with the same numerals. With reference to FIG. 1 , the machine 10 receives wire stock 18 at a cut off station 19 where, during each cycle of the slide 12 , a precise length of material 26 , hereinafter referred to as a bolt, is severed by a pair of shear plates 22 , 23 . A transfer of known design moves the bolt 26 from the cut off station 19 to the successive work stations 13 - 16 , each time the slide 12 reciprocates.
FIG. 1 illustrates the progressive formation of pointed and eventually threaded to the head hex flange head bolts that, when rolled with a thread, can conform to the European standard DIN EN 1662, for example. When a bolt is removed from the last station in any of the bolt types disclosed herein, it will be finish headed, pointed, and ready for roll threading on a roll diameter on its shank.
When the slide or ram 12 is retracted from its illustrated position, the bolt 26 is transferred to the first station 13 , it being understood that any preceding bolts in the first and subsequent stations 14 - 16 are simultaneously indexed or transferred to the next station and eventually discharged after forming in the fourth or last station 16 .
The bolt 26 , in the sequence depicted in FIG. 1 , has its shank portion received in a die or insert tool 27 on the die breast 11 and its head portion initially upset in an insert tool 28 on the slide 12 at the first station 13 . The diameter of the wire supplied to the cut off station 19 is substantially equal to, i.e. slightly smaller, e.g. a few thousandths of an inch, than the ideal or nominal roll or pitch diameter of a finished shank to account for any incidental growth in diameter in the first station 13 and subsequent stations 14 - 16 . The nominal roll diameter at the first station 13 and subsequent stations 14 - 16 exists along the full length of the shank so that the part can be of the threaded to the head style of fastener.
The bolt 26 is transferred to the second work station 14 during the next machine cycle. Here, a hex shape is extruded on the head of the bolt 26 by a pair of tools 29 , 30 on the die breast 11 and slide 12 , respectively. Next, the bolt 26 is transferred to the third station 15 where a flange is formed between die and punch tools 31 , 32 . Thereafter, the bolt 26 is transferred to the fourth or last forming station 16 where the flanged head is supported in a sleeve 33 on the slide 12 and the distal end of the shank is pointed in an extrusion die 42 . A spring assembly 43 is disposed in the sleeve 33 and is effective in temporarily supporting the bolt 26 to facilitate transferring action. FIG. 8 illustrates the forth station 16 in a vertical cross-section on a somewhat enlarged scale over FIG. 1 .
FIG. 7 illustrates the sleeve 33 in exploded relation to a case 44 in which it is selectively axially positioned in accordance with the length of bolt 26 being produced. A forward face or surface 46 of the sleeve 33 supports the head of the bolt 26 during the pointing or forming step at the fourth station 16 depicted in FIG. 1 . Both the sleeve 33 and case 44 are generally cylindrical tubular bodies. An outside diameter or surface 47 of the sleeve 33 is proportioned with a close fit to a bore 48 of the case 44 . The exterior 47 of the sleeve 33 is cut with pairs of opposed chordal slots 51 . The case 44 is similarly cut with pairs of opposed chordal slots 52 that extend through the wall of the case.
The axial position of the sleeve 33 in the case 44 is fixed by a pair of identical keys 53 having chordal profiles. Outer circular or peripheral areas 56 of the keys 53 have a radius that is essentially the same as the radius of the outer surface of the cylindrical case 44 . The axial dimension of the major thickness of the keys 53 provides a close fit with the axial length or width of the case slots 52 . At their central area, the keys 53 have chordal webs 57 of an axial thickness half that of the outer or major parts of the keys and are sized to closely fit into the slots or notches 51 in the sleeve 33 . Preferably, the axial dimensions of the key webs 57 , key periphery 56 , sleeve slots 51 , sleeve slot axial spacings, case slots 52 , and case slot spacings are all units or multiples of the increments that the standard bolts differ in length, e.g. 2, 4, or 5 mm. When tooling is set up to make a particular bolt length, the sleeve 33 is positioned in the case 44 at a desired location, the keys 53 are placed in whichever sleeve and case slots 51 , 52 line up (on each side of the case) and this sleeve, case, and key assembly is slipped into the sleeve of the respective work station 16 ( FIGS. 1 and 5 ) or 15 ( FIGS. 3 and 4 ). By properly setting the sleeve 33 in the case 44 , standard length threaded to the head bolts can be produced using the same pointing die 42 .
A bolt with a head having a hex shape or otherwise non-circular form should not rotate when being transferred from one station to another, so that the head will be angularly registered with the tools at the succeeding station. The risk of unwanted rotation, in accordance with the invention, is reduced by locking the part against such rotation, while it is being picked up by the transfer fingers, with a formation of a small diametral chisel edge or projection 60 on the end face of knockout pins 61 in the relevant work stations. At various stations, a knockout pin 61 lies at the center line of a work station. Typically, the knockout pin extends through a bore 65 in hard plate 62 mounted on the die breast 11 and backing up or axially supporting the tooling against forming loads at the respective die station. With reference to FIG. 10 , the angular orientation or position of the hard plate 62 in a cylindrical bore 63 of a circular case 64 is maintained, in accordance with the invention, by headless set screws 66 received in axially oriented, threaded, semi-circular slots 67 in quadrature on its periphery and open to the bore 63 . The hard plate 62 has a complementary set of axially extending semi-circular slots 68 arranged, in quadrature, on its periphery to register with and complement the slots 67 in the bore 63 . The associated knockout pin 61 and, therefore, its chisel end face is maintained in a proper orientation with reference to the hard plate 62 by a shoe 69 biased by bevel springs 71 against an elongated flat 72 on a side of the knockout pin. The springs 71 and shoe 69 are retained in a radial bore 73 in the hard plate 62 by an axially oriented pin 74 . The shoe 69 , bearing against the flat 72 , allows the pin 61 to reciprocate but prevents rotation of the pin about its longitudinal axis.
FIG. 2 illustrates the inventive process and tooling as applied to producing standard hex flange bolts, again under the European standard DIN EN 1662 where the standard lengths are greater than the standard threaded to the head lengths as discussed with respect to FIG. 1 above. Machine elements or parts that are the same or similar to that described in connection with FIG. 1 are identified with the same numerals here in FIG. 2 and, below, with reference to FIGS. 3 through 5 , and certain other figures. The sequence of transferring bolts discussed in reference to FIG. 1 , similarly, is the same for the tooling set ups in FIGS. 2 through 5 . The bolt 76 begins successive heading, pointing, and roll diameter formation at the first work station 13 where it is upset to partially form the head with punch and die tools 77 , and 78 . At the second forming station 14 , a hex shape is extruded on the head by cooperating tools 79 , 80 on the slide 12 and die breast 11 , respectively. In the third work station 15 , opposed tools 83 and 84 form the flange of the head in an upset action, and a tool or die insert 39 in a limited extrusion like action forms a point on the distal end of the bolt shank.
At the fourth station 16 also depicted in a vertical cross-section in FIG. 9 , the distal end of the bolt shank is extruded in a die insert or tool 86 reducing its diameter to that of a roll diameter along a length corresponding to a standard thread length. The head of the bolt 76 at this station 16 is axially supported and driven by the sleeve 33 described above in connection with FIG. 7 . In the set-up of FIG. 2 , the sleeve 33 is held by the keys 53 towards the rear of the case 44 such that the head and a significant portion of the shank is received in the case. The stepwise multiple positions of the sleeve, similar to its use in the process described in connection with FIG. 1 , allows a single die insert 86 to be used to extrude the roll diameter on a plurality of lengths and preferably the full range of standard lengths of partially threaded bolts.
Returning to the discussion of the process at the third station 15 , differences in the lengths of bolts in a standard range are, in accordance with the invention, accounted for by axially shifting a pointing tool or insert in its respective case and/or substituting another insert with an incrementally different axial location of the pointing area or throat in the insert, the differences in location corresponding to differences in standard bolt lengths. FIGS. 6 a - i , illustrate these variations, the numerals 37 , 38 , 39 and 40 identifying different inserts. The elements 34 are fillers of equal length.
FIG. 3 illustrates the inventive process and tooling applied to making threaded to the head hex head screws or bolts such as conforming to European Standard DIN EN ISO 4017. Like the process shown in FIG. 1 , wire stock fed to the cut off station 19 is slightly less than the nominal roll diameter of the finished blank. At the first station 13 , a bolt 91 , with this near a roll diameter along substantially the full length of its shank, has its head initially coned or upset in punch and die tools 92 , 93 , respectively. At the second station 14 , the head is further upset between punch and die tools 94 , 95 . The bolt 91 is pointed in an extrusion like process in a die 96 on the die breast 11 at the third station 15 . Differences in the lengths of hex head bolts are accounted for by the multiple position sleeve 33 , optionally having its face modified to conform to the intermediate head profile of the bolt 91 at this station 15 with the case 44 and keys 53 as disclosed in connection with the set up of FIG. 1 . Additionally, the die or insert 96 can be double ended and reversed end for end to change the axial location of the operative extrusion like pointing throat and thereby supplement the range of position adjustment offered by the sleeve 33 carried on the slide 12 . The cross section of the head of the bolt 91 preferably produced in the first two stations 13 , 14 , is generally circular. In the fourth station 16 , the head of the bolt 91 is trimmed into a hex between opposed tools 97 , 98 .
Referring to FIG. 4 , conventional partially threaded hex head pointed bolts are made with the inventive process and tooling. Such bolts can conform to the DIN EN ISO 4014 standard. The head of a bolt 101 is initially headed or coned at the first station 13 between tools 102 , 103 . At the second station 14 , the head is further upset by tools 104 , 105 and the distal end of the shank is pointed by an extrusion like tool 39 . The specific length of the bolt 101 is accounted for by using the dies, fillers, and techniques described in connection with FIGS. 2 and 6 with reference to the set up at the third station of FIG. 2 . The roll diameter of the bolt 101 is extruded on the shank at the third station 15 in a tool or insert 86 which can be the same tool as used in the set up of FIG. 2 at the fourth station 16 . Variations in the length of the bolt 101 can be accommodated by the multi-position sleeve 33 as explained above. The head of the bolt 101 is trimmed to a hex shape at the fourth station by tools 106 , 107 .
FIG. 5 illustrates the method and tooling by which the invention produces threaded to the head socket head cap screws 111 such as specified in the DIN EN ISO 4762 standard. Again, like the processes shown in FIGS. 1 and 3 , wire stock fed to the cut off station 19 is slightly less than the nominal roll diameter of the finished blank to account for incidental growth in diameter at the work stations 12 - 16 . The bolt 111 with the near roll diameter along its shank has its head initially upset in the first station 13 in die and punch tools 112 , 113 . At the second station 14 , the bolt 111 is progressively formed by further upsetting the head in tools 114 , 115 . At the third station 15 , the bolt head is fully upset and formed with an internal hexagonal blind hole with punch and die tools 116 , 117 . At the last station 16 , the part is forced into a die tool the same as or like the tool 42 used on the last die station illustrated in FIG. 1 . As in FIG. 1 , the sleeve 33 or an equivalent thereof can be appropriately positioned in the case 44 on the slide in the last station 16 to account for differences in the lengths of the bolts 111 being produced.
While the invention has been shown and described with respect to particular embodiments thereof, this is for the purpose of illustration rather than limitation, and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention. Accordingly, the patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention. | A set of tooling for making pointed headed bolts of a given diameter in numerous lengths with roll thread ready threaded to the head and partially threaded shanks in a four forming station forming machine, the tools being configured to work on wire stock as received at the first station of a diameter larger than or substantially the same as the roll diameter and not greater than the nominal diameter of the bolt, including at least two sequential head forming tools for mounting on the slide, an extrusion pointing tool for mounting on the die breast, a roll diameter extrusion tool for mounting on the die breast and a head support tool mountable in a station on the slide at multiple axial positions corresponding to standard lengths of the bolts being made, the head support tool being arranged to work at either the extrusion pointing station or the roll diameter extrusion station. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to apparatus for rapid inspection of flat-rolled products while on-line at relatively high temperature with an accuracy, ease, and economy heretofore unknown in the industry utilizing ultrasonic detection of internal defects in flat-rolled products through streams of liquid applied to the flat-rolled products and synchronization of the flat products on the mill line with the automatic electronic instrumentation of the apparatus.
Available apparatus of the type of the present invention have one or more of the following disadvantages such as a much higher initial cost or maintenance cost, less inspection coverage, causing an obstruction of the passline, not being capable of reliable inspection at temperatures above 150° C. and not being able to follow contour variations. Designs with one or more of these disadvantages are found in closely related patents U.S. Pat. No. 3,625,051; Belgium Pat. No. 744,628; and U.S. Pat. No. 3,979,946 referring to ultrasonic measuring and inspecting systems.
Also the synchronizing of product motion for operation of the automatic controls as attempted in prior art devices now in use are designed with these devices mounted above the mill line and therefore present an obstruction along the line which prevents a crane from placing or removing anything in the area of the device.
SUMMARY OF THE INVENTION
It is an object of the present invention to eliminate all the disadvantages of the prior art devices within a rugged design.
Advantages of the present invention include the use of less water due to a circulation system, unobstructed pass-line, more tolerance to waviness in the flat-rolled product, better overall inspection resolution, inspection permitted at higher temperatures, and relative simplicity of construction, installation, and maintenance.
It is a further object of the present invention to locate the inspection device below the pass-line in order to maintain an unobstructed pass-line.
It is still a further object of the present invention to incorporate an immersion inspection technique in the invention to obtain better inspection resolution.
It is another object of the present invention to have a device which senses a flat product as it approaches a fixed location on a production line, and synchronizes the forward and backward movement of the product as the product passes over a fixed location.
Basically the present invention relates to a carriage for mechanically supporting and positioning an array of ultrasonic transducers used to ultrasonically detect internal defects in flat-rolled products, such as steel plates, and a delivery and storage system for providing a liquid such as water, that is used to cool the surface of warm (up to about 700° F.) flat-rolled products and also to provide a means for coupling ultrasound to and from the piece being inspected.
It is also an object of the present invention to install it on a mill line with suitable transducers and electronic instrumentation to provide a means for rapid one hundred percent ultrasonic inspection of both cool and warm (in the vicinity of 700° F.) flat-rolled products on-line during the production process.
A still further object of the present invention is to maintain vertical, horizontal, and axial adjustment of the transducer array.
In general the present invention comprises:
means for coupling ultrasonic energy to and from the tested piece and the transducer by means of both low pressure, high volume and at the same time velocity, low volume liquid flow;
means for supporting the transducer array and coupling assembly beneath a mill line on a suspension system that is independent from the main supporting assembly;
serrated roller means of contact with the inspected piece that allows a uniform or constant position of the transducer array relative to the test piece surface; and
means for collecting ultrasonic coupling and cooling fluid, filtering it, storing it and recirculating it to the transducer through both low and high pressure lines.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and advantages of the invention will become apparent upon full consideration of the following detailed description and accompanying drawings in which:
FIG. 1 is a block diagram of the overall system of the present invention;
FIG. 2 is a partially sectioned transverse elevation of the on-line portion of the present invention and a view of connecting apparatus;
FIG. 3 is a partially sectioned enlarged view of the under-plate ultrasonic flow detector unit along line 3--3 of FIG. 2;
FIG. 4 is a plan view of the unit of FIG. 3;
FIG. 5 is a plan view of units similar to those of FIG. 3 but located for full width inspection;
FIG. 6 is an elevation of the embodiment of FIG. 5 along line 6--6 of FIG. 5;
FIG. 7 is a perspective view of the rotor pulser and plate sensor unit from one side of the unit; and
FIG. 8 is a perspective view of the unit in FIG. 7 from the opposite side.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1 there is shown an overall block diagram of the apparatus of the present invention for on-line ultrasonic inspection of steel plates.
A steel plate 10 which may still be at a high temperature is moved over roll table 11 from a hot bed and marking area. In between a pair of rollers 12 there is located an under-plate flaw detector unit 15 which performs inspections utilizing ultrasonics on plates 10 as they pass over the rollers and unit 15. Also located in the passline is a serrated wheel 16 driven by plate 10 as it passes over it. Wheel 16 is mechanically connected to rotor pulser 17 which is used to determine the position and change of position of plate 10 on the pass-line. The ultrasonic inspection of flaw detector unit 15 utilizes water from reservoir 20 which is delivered both through flooding pump 21 in a low pressure, high volume stream through hose line 22 to flaw detector unit 15 and through spray pump 23 in a high pressure, low volume stream through hose line 24 to unit 15. After use the water from unit 15 passes through water drain sump and filter 25 through return pump 26 to reservoir 20 for further use in the system.
A remote mill terminal 30 connects to flaw detector 15 so as to operate unit 15 with proper signals and receiving information as to any flaws in plates 10 therefrom. At the same time plate travel is synchronized with the electronic instrumentation through information received from rotor pulser 17 which is mechanically connected to wheel 16 which is spring loaded to maintain frictional contact with the bottom of plate 10. Combined with information from plate sensor switch 18 the pressure of a plate 10 as well as forward and backward plate motion are sensed. Remote mill terminal 30 activates main ultrasonic instrument 31 which through ultrasonic data buffer/controller 32 supplies ultrasonic power to flaw detector unit 15 and supplies the information to minicomputer 33 and printer 34 and CRT display 35 to indicate flaws. Channel selector switch 36 chooses the ultrasonic transducer/channel/s whose signals will be displayed on the ultrasonic display screen 37, as plate 10 moves over flaw detector unit 15.
Flaw detector unit 15 is shown in FIG. 2 in its mounting and with its hose connections to reservoir 20. Further details of the internal structure of unit 15 is shown in elevation and plan views in FIGS. 3 and 4 respectively.
Refering to FIG. 2 there is shown a steel container 40 into which water runs and which contains an ultrasonic transducer fixture. Container 40 with a transducer array therein is mounted on a wheeled carriage 41. Container 40 is cantilevered on carriage 41 by a set of hinged parallel bars 42. A bellows type air bag 43 supports the cantilevered container 40 and permits the raising and lowering of it by remote pneumatic control. If desired, the air bag remote control may be connected to a sensing device located upstream from the transducer container 40 so that it can automatically retract air bag 43 if a severely bent plate is sensed at the upstream sensing device. Wheeled carriage 41 rests on tracks 44 supported within a water collection trough and sump 46 (or 25 of FIG. 1). An air cylinder 47 on carriage 41 has its piston 48 connected to the side of trough 46 through connecting rod 49. Thus it is possible to control the position of carriage 41 for transverse movement across mill line or pass-line by remote pneumatic control. Flexible hoses 22 and 24 respectively carry low pressure, high volume and high pressure, low volume liquid from reservoir 20 to container 40. Liquid overflowing transducer container 40 is collected in sump trough 46 and returned to the reservoir 20 via filter 51 and flexible hose 52. The water collection, filtering and storage reservoir reduces the amount of water usage and permits economical use of various additions to the water such as anti-freeze and/or wetting agents by reducing the need for continual make-up as is the case in existing systems that continually drain away coupling water.
Container 40 as shown in more detail in FIGS. 3 and 4 has a water flow into the container through flexible hose 22 at inlet 55 at a rate between 175 and 200 gpm. As the water fills portion 56 of container 40, the container walls act as a weir and hydraulic equations for water flowing over a weir apply. A plate 10 moving over the top of container 40 is wetted on its lower surface by the water as it swells up over the container walls. Mounted in container 40 is a spring loaded assembly 60. On assembly 60 are grooved or serrated rollers or cylinders 61 and 62 mounted so that their axes of rotation are parallel to the plane of a plate 10 and perpendicular to the direction of travel of that plate 10. Between rollers or rolls 61 and 62 is a transducer mounting bar 63. Container 40 is generally mounted between pass-line rolls 12 on a plate mill so that the upper rims of serrated rolls 61 and 62 rise a distance above the pass-line rolls 12 equal to the expected maximum waviness of the plate 10 to be inspected. In the embodiment of a plate mill illustrated serrated rolls 61 and 62 may be placed so as not to exceed one inch above the pass-line. As plates 10 move down the production line, their bottom surface contacts serrated rolls 61 and 62 which causes assembly 60 in container 40 to be compressed against springs 64. This spring pressure causes serrated rolls 61 and 62 to follow the bottom surface contour of plate 10 and thus maintain uniform positioning of transducers 65 with respect to the lower plate surface as plate 10 moves over assembly 60. The independently suspended or isolated transducer array shown makes it possible for the array of transducers 65 to follow wavy surfaces on plates 10 and thereby maintain a constant distance between transducers 65 and plate 10. Also the ultrasonic beam can be maintained relatively normal to the inspected piece surface regardless of the up and down motion of the piece due to waviness of plate 10. If it is desired and as shown in the present embodiment, transducer mounting bar 63 can have means for adjustment for transverse alignment of transducers 65 and also serrated roll 62 can be supported by an eccentric shaft 66 that permits longitudinal adjustment of transducers 65. Flowing water contacting the bottom of plate 10 provides ultrasonic coupling with transducers 65 in a manner similar to a standard immersion test. The low pressure, high volume liquid supply makes it possible to position the ultrasonic transducers away from the inspected plate surface while ultrasonic coupling is achieved through a liquid column. Thus, the risk of transducer damage from rough or projecting surfaces of the inspected plate is greatly reduced. The type of inspection performed is similar in principle to immersion type inspection which is recognized by those familiar with ultrasonic inspection as producing more consistant results and higher resolution than most other common methods of ultrasonic inspection.
Also mounted on spring loaded assembly 60 is a separate fluid chamber 70 with slotted orifice 71 that directs water at an angle of 27° or less relative to the bottom surface of plate 10 in a direction opposite to plate travel. A separate inlet 72 to chamber 70 is connected to flexible hose 24 which extends into container 40 and through which liquid at higher pressure than the liquid in portion 56 of container 40 enters chamber 70 and is directed through orifice 71 onto the bottom surface of plate 10 with high enough velocity to wash away steam and vapor and to temporarily cool the surface of plate 10 which may be at a temperature of about 700° F. Ultrasonic coupling into a warm plate is thereby affected. Water pressure in slotted chamber 70 is such that the velocity of the water and the opposing plate velocity combine to produce an apparent liquid velocity of at least 44 feet per second impinging on the plate surface. For a warm plate, coupling fluid temperature should be as low as possible to inhibit rapid steam generation. The high velocity, low volume liquid flow permits inspection at higher plate temperatures because a flow is produced which when directed tangentially onto the plate surface serves to temporarily cool the surface and wash generated steam away from the ultrasonically inspected area.
The embodiment described above requires transverse adjustment of the transducer array and possibly several passes of a plate 10 in order to inspect the full width. FIGS. 5 and 6 disclose another embodiment allowing ultrasonic inspection of the full width during a single pass. A series of containers 40' with serrated rolls 61', and 62' and arrays of transducers 65' are installed across a mill line between pass rolls 12. Containers 40' are positioned in staggered fashion so that the inspection path from an array of transducers 65' in one container 40' is adjacent to the inspection path of an array of transducers 65' in another container 40' with no intervening uninspected space. Low and high pressure liquid is supplied to containers 40' through manifolds 22' and 24' respectively located under the transducer arrays. Connecting pipes and flexible hoses connect low pressure manifold 22' to chamber 74 from which flooding water passes through openings 76 to portion 75 from which the water wets the bottom surface of plate 10 while it is overflowing. Other connecting pipes and flexible hoses connect spray manifold 24' to chamber 77 from which spray is ejected from orifice 78 against plate 10. Each array of transducers 65' with serrated rolls 61' and 62' and flooding and spraying structure is supported by air bags 79 that provide the constant contact of rolls 61' and 62' on the bottom surface of plate 10. Ramps 81 leading to and from serrated rolls 61' and 62' serve to reduce mechanical shock to transducer arrays 65' as a plate 10 approaches the inspection fixture. The combination of ramps 81 with the staggered transducer arrays 65' minimize the possibility that bent plates can damage transducer arrays 65'. The entire assembly can be fixed on a framework that can be installed as one piece and supported on an existing pass-line framework. Liquid supply pumps, reservoir and filters may be located on the side of the pass-line near the on-line assembly.
FIGS. 7 and 8 are detail views of rotor pulser 17 showing its mechanical construction. The roto-pulse assembly 85 is mounted on a pair of vertical plates 84 welded to a base plate 86 with a shaft 87 rigidly attached to one end of assembly 85 and passing through bushings on vertical plates 84. A spring mechanism 88 spaced horizontally on the other end of assembly 85 from shaft 87, and stop mechanism 89, permit assembly 85 to be fixed at one point relative to vertical plates 84 and base plate 86 yet able to travel through a limited arc rotated on shaft 87 when the pressure of spring mechanism 88 is overcome. Rigidly connected to an extension of shaft 87 is a cam 90 that activates a limit switch 91 (such as plate sensor switch 18 as in FIG. 1), mounted to base plate 86, when the roto-pulse assembly 85 moves down slightly on spring mechanism 88 from its fixed bias point in a movement with shaft 87. On assembly 85 another shaft 92 passes through bushings on the hinged assembly 85 and is rigidly attached to a serrated roller 93. The roller 93 (serrated wheel 16 of FIG. 1) is located in assembly 85 such that the top sections 94 and sidewalls 95 of assembly 85 protect roller 93. A sprocket 96 and chain 97 connect serrated roller 93 to sprocket 98 which is connected to a commercially available rotary pulse generator 99 such as is manufactured by Gould, Incorporated, Control Systems Division of Wilmington, Maine. Rotary pulse generator 99 is also mounted on roto-pulse assembly 85 on the opposite side of a sidewall 95 from sprocket 98. Electrical cable connects from rotary pulse generator 99 to remote synchronizing and timing circuitry.
The entire roto-pulse assembly 85 is mounted between rolls 12 on a production line such that the circumference of serrated roller 93 rises above the pass-line at a distance equal to the expected maximum waviness of the product plate 10 to be tracked. The top sections 94 of roto-pulse assembly 85 then act as ramps in front of and behind serrated roller 93 and serve to cushion the impact as the plate contacts assembly 85. As plate 10 approaches assembly 85 serrated roller 93 is depressed and cam 90 depresses the follower 100 on switch 91 which is used to enable the synchronizing instrumentation. As plate 10 moves over assembly 85 serrated roller 93 follows the lower surface of plate 10. Friction causes roller 93 to rotate and in turn causes rotary pulse generator 99 to rotate and produce a series of electrical pulses that are synchronized with plate 10 movement. Rotor pulser unit 17 feeds the electrical pulses to remote mill terminal 30. The serrations on roller 93 reduce the possibility that small particles clinging to the surface of plate 10 will cause assembly 85 to skip or miss pulses. An air cylinder 101 under roto-pulse assembly 85 permits the assembly to be retracted beneath the pass-line when not in use or when conditions on the line could damage it if it were left engaged. A beveled fillet 102 along the side of assembly 85 permits plate 10 to be shifted sideways on and off assembly 85 with no damage.
By use of roto-pulse assembly 85 with rotary pulse generator 99 and ultrasonic flaw detector unit 15 with its associated parts, flaws are detected in plates 10 and accurate recording of the location of these flaws can be made.
It will be obvious to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown in the drawings and described in the specification. | Apparatus and method for acoustically inspecting hot flat plates while on-line by utilizing an array or arrays of transducers continually spaced a set distance from the bottom of the plates by serrated rollers spring mounted with the array of transducers in a container with overflowing liquid wetting the passing plate to acoustically couple the transducers to the plate and a spray of sufficient force to temporarily cool the hot plate and dispel steam and vapor formed, the spray being in a direction opposite the direction of travel of the hot plate; and support of the unit on a track mounted carriage, with the liquid reused through a reservoir connected system. It is critical that the spray be at an angle of 27° or less to the horizontal and that the spray have sufficient force to have an apparent liquid velocity of at least 44 feet per second, adding the speed of the water and the hot plate together. Also includes associated electronic instrumentation and a rotary pulser with spring biased hinged mounted serrated roller having a cam activated limit switch for enabling the electronic instrumentation and a sprocket and chain connection from the serrated roller to a rotary pulse generator for detecting the position of the plates. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention pertains generally to computers. In particular, it pertains to computer memories.
2. Description of the Related Art
Various types of semiconductor memory are used in computers, each with its own characteristics. Some types of memory are charge-based. Charge-based memories charge up a cell to a predetermined level that represents the desired logic state. For example, a logic ‘0’ could be programmed by charging up the cell to a level above 1.5 volts, while a logic ‘1’ could be represented by keeping the charge in the cell below 1.5 volts. In some types of memories, multiple states can be represented by defining multiple ranges of charge. For example, ‘11’ might be represented by 0-1.5 volts, ‘10’ by 1.6-3.0 volts, ‘01’ by 3.1-4.5 volts, and ‘00’ by greater than 4.6-6.0 volts.
Most charge-based memories are reprogrammable while in the circuit, and many retain their data for a period of time even when electrical power is removed from them. In the programming operation, each cell can be charged up to a given state. Because of the mechanism involved in charging or discharging, an erase operation is generally performed on a large number of cells at the same time. These types of memories are generically referred to as electrically erasable read only memory (EEPROM), of which flash memories are one type. With EEPROM's, an entire block of memory must generally be erased and reprogrammed whenever any of the contents of the block are to be changed.
Once a charge-based memory cell has been programmed, it is read by comparing the amount of charge in the cell with a reference threshold level. For example, if the threshold between a logic ‘0’ and a logic ‘1’ is 1.5 volts, a reference cell will be maintained at 1.5 volts. The voltage level in the cell being read is compared to the reference voltage. If it is less than that reference voltage level, it is determined to be in one state, while if above the reference voltage level, it is determined to be in another state.
Once a memory cell has been charged to a certain level, that charge can migrate away, or ‘leak’, until the remaining charge represents a different, i.e. incorrect, state. If the charge migrates until the voltage in the cell is approximately the same as the reference level, the logic state stored in the cell can be misread, resulting in a memory failure. This is especially a problem in multi-state memory cells, in which each of the states are compressed into a relatively small voltage range.
Different types of technology are able to retain data for different periods of time before failing in this manner. Flash memory can retain data for several years without any effort to renew the charge. The amount of time a memory cell will remain ‘good’, i.e., will reliably hold a charge within the desired range, depends not only on the technology used, but can also depend on the characteristics of the memory's usage. Flash memories, for example, begin to deteriorate after program/erase cycles due to a change in the rate of leakage. Other factors can also affect the rate of this leakage, such as the bias voltages used and the operating temperature. Even the size of the memory array is a consideration (a large array is statistically more likely to have a bad cell that leaks faster, and just one bad cell can be enough to cause the memory device to fail).
FIG. 1 a shows characteristic curves for conventional flash memory cells. In FIG. 1 a , the charge level representing the programmed state P and the charge level representing the erased state E leak, so that over a period of time, both approach threshold reference voltage Vth. The memory device eventually fails at time T 1 , because the charge level in that cell can no longer be reliably distinguished from the threshold voltage in at least one of the states.
In FIG. 1 b , due to the operational factors discussed above, the erased state leaks faster than the programmed state, and the device fails at time T 2 because the erased state can no longer be distinguished from the reference voltage. Although the programmed state has a much longer lifetime remaining, the memory device is not functional if it cannot reliably distinguish both the programmed and erased states for all cells. In FIG. 1 c , the programmed state deteriorates much faster than the erased state, so that the part fails at time T 3 , even though the erased state might be able to operate reliably for several more years.
In conventional memories, the reference voltage Vth is determined by assuming an average usage and deterioration, such as that shown in FIG. 1 a . Because of this, actual usage profiles that follow the curves of FIG. 1 b or 1 c result in premature failure of the memory cells, because one of the states approaches the reference voltage threshold much faster than the other state.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 a - 1 c show the deterioration characteristics of a conventional charge-based memory.
FIGS. 2 a - 2 b show threshold values for single-state and multi-state cells.
FIGS. 3 a - 3 c show leakage curves for single-state and multi-state cells.
FIGS. 4 a - 4 b shows a comparison between various types of leakage curves for single-state cells.
FIG. 5 shows threshold values adjusted for customized leakage curves.
FIG. 6 shows the use of guard bands with customized leakage curves.
FIG. 7 shows a flow chart of a method.
FIG. 8 shows a memory apparatus and system.
DETAILED DESCRIPTION OF THE INVENTION
Various embodiments of the invention use a threshold reference voltage to fit the anticipated usage characteristics of the memory. Some embodiments provide a reference voltage from a memory cell, much like the addressable memory cells, but the reference cells are sealed off from further charge adjustments once they have been charged up to the desired reference thresholds. By determining the anticipated usage characteristics, or usage profile, of a given group of memory devices, each group can have its reference threshold set to maximize the memory's lifetime for those usage characteristics. A usage profile can consist of a combination of the various usage factors that are expected to affect the operation of a given memory, and the resulting effects on the leakage curves of that memory. Such factors can include bias voltages, the number of erase and/or program cycles, operating temperature, array size, and the underlying technology and materials of the memory.
Adjusting for the usage profile by charging up the reference cells to different levels is much easier and less expensive than changing reference schemes by design or during process fabrication. Although setting the reference voltage levels can typically be performed by the memory chip manufacturer, with inputs from the customers about anticipated usage, this step can also be performed further downstream by anyone in the manufacturing or distribution chain that has the proper equipment to program the reference voltage levels. Thus, this technique permits the customized reference levels to be set either by the memory chip manufacturer or by those that are closer to the end user and therefore are more familiar with the usage characteristics that are anticipated.
The various embodiments described herein are described in terms of flash memory. This is for illustration only, and the invention is equally applicable to other types of memory to place memory cells in different logic states, and then compare against predetermined references to determine what state a memory cell is in.
As is well known in the art, flash memory uses a transistor with a floating-gate to provide non-volatile storage for data. By using one set of bias voltages on the transistor, the charge on the floating gate can be eliminated or reduced to a minimal level (erased). By using a second set of bias voltages on the transistor, the floating gate can be charged up to a predetermined level (programmed). A third set of bias voltages on the transistor can be used to read the level of charge. The amount of charge on the floating gate affects the conductance of the transistor when it is read, so the read operation consists of placing the transistor in a read state and measuring either the current or voltage between the source and drain. This measured quantity is then compared with a reference to determine if the detected charge level is above or below a threshold value. The examples described herein use voltages as the relevant value, but a person of ordinary skill in the art can easily apply the same principles to currents or other forms of measuring the memory cell. The relevant quantity can be generically referred to a ‘value’, which can include voltage, current, or charge, depending on the parameters being used.
In a single-state memory cell, only a single data bit is stored. Since a data bit can actually have two states, one state may be considered the ‘1’ state and the other state may be considered the ‘0’ state. For convenience of illustration, the ‘1’ state will be considered to represent an erased state, while the ‘0’ state will be considered to represent a programmed state, but the opposite convention can also be used. Thus, the term “single-state memory cell” can refer to the number of programmed states available. Using a single threshold voltage as a reference, the read circuitry can determine if the measured voltage is above or below the reference voltage. FIG. 2 a shows this for one embodiment of a single-state memory cell, in which the memory cell can be erased and programmed to produce a read voltage anywhere from the ‘Min’ to ‘Max’ levels. Reference voltage Vth is the threshold reference voltage. In this embodiment, if the addressed memory cell produces a read voltage between Vth and Min, it is considered to be in the erased state. If the addressed memory cell produces a read voltage between Vth and ‘Max’, it is considered to be in the programmed state.
FIG. 2 b provides a similar illustration for a multi-state memory cell that can represent four possible states, although other configurations are also possible. As in FIG. 2 a , when erased and programmed, the floating gate of the transistor can be charged up to any level that produces a read voltage between ‘Min’ and ‘Max’. Three different threshold voltages, Vth 1 , Vth 1 , and Vth 3 , divide this into four ranges. In this embodiment, a read voltage in the E range is considered to be in the erased state, while a read voltage in the P 1 range is considered to be in the first programmed state. The P 2 and P 3 ranges represent the second and third programmed states. In one embodiment, the ranges E, P 1 , P 2 , and P 3 can represent logic values 11, 10, 01, and 00, respectively, but other conventions can also be used, as is known in the art. Multi-state memory cells can therefore be used to store more than one logic bit per cell. The number of states that can be reliably represented in a single cell depends on the number of states that can be reliably programmed and read. As shown, multi-state cells can have narrower voltage ranges for each state than single-state cells, and the program/read operations should therefore be controlled more tightly, making them potentially more difficult and expensive to produce.
Flash memory cells can retain a charge for a long time, such as for several years. However, once programmed, this charge will inevitably leak, or migrate away from the floating gate with time, until the read voltage approaches one of the threshold voltage levels. When the read voltage comes so close to the threshold voltage that they cannot be reliably distinguished from each other, the state of the cell can be misread and the memory cell can fail. In one embodiment, this process may take several years, but the contents of many flash memories are frequently intended to remain unchanged for the lifetime of the product, and even a multi-year leakage rate may shorten the effective life of that product.
FIG. 3 a shows this migration effect for single-state memory cells. The cells are initially programmed to voltage levels Ex for a logic ‘1’ or Px for a logic ‘0’. But with time, as the charge leaks away from the floating gate, the read voltage of the cells can follow the curves to Ey and Py, respectively. Eventually, one of those voltages will come so close to Vth that it will not register as different than Vth, and the state of the memory cell will not be able to be reliably determined, resulting in failure of the memory cell. Since a failure of only one cell can effectively result in a failure of the entire memory, the worst-case cell may determine the lifetime of the entire system. FIG. 3 b shows the same thing for a multi-state memory cell, with the voltages Ex, P 1 x , P 2 x , and P 3 x gradually declining to Ey, P 1 y , P 2 y , and P 3 y , respectively. In the illustrated embodiment, the voltage in the erased state drifts in an upward direction, while the voltages in the three programmed states all drift in a downward direction. This directional orientation can be dependent on the particular bias voltages being used, the materials in the memory cell, and other factors, so the direction of drift can be different in other embodiments. Regardless of the direction of drift, the voltage of an erased or programmed state can eventually approach a threshold value and result in a memory failure. In some embodiments, the memory can include two separate reference cells for two separate thresholds between two states, such as shown in FIG. 3 c , where Vthp represents the lower threshold for the programmed cells, and Vthe represents the upper threshold for the erased cells. This provides a guard band between states in which neither state is valid, thus allowing separate control over the allowable boundaries of each state.
The rate at which an erased or programmed state drifts can depend on a number of factors, such as the bias voltages used, the number of erase/program cycles performed on the cell, the temperature of the device, the materials used in making the memory, the type of memory product, and others. Each of these factors may affect the erased state more or less than the programmed state, or in a multi-state cell may affect some programmed states more than others. Because of this, the voltage in one state may drift faster than the voltage in another state, as was previously shown in FIGS. 1 a - 1 c , causing a premature memory failure. Statistically, a large number of memory cells are more likely to contain a deficient cell that drifts faster than the average, resulting in an earlier memory failure. Since the failure of a single cell is generally enough to cause the entire memory to be considered unreliable, a large memory array may be predicted to have an effectively greater rate of drift and effectively shorter time-to-failure than a smaller memory array.
All of these factors can be included in the ‘usage profile’ for a given memory, and a predicted rate of drift can be determined for each erased or programmed level. The specifics of making these predictions is known in the art and is not further described to avoid obscuring the invention. A graph of the predicted drift is known as the leakage curve. The leakage curves for one embodiment of single-state memory is shown in FIG. 3 a , while the leakage curves for one embodiment of multi-state memory is shown in FIG. 3 b . In these two examples, the reference voltages Vth (FIG. 3 a ) and Vth 1 , Vth 2 , Vth 3 (FIG. 3 b ) can be adjusted to maximize the time it takes for each curve to reach its associated reference voltage, and theoretically maximize the predicted lifetime of the memory. In a conventional memory, the same ‘average’ usage curves are used to set the same Vth (or Vth 1 , Vth 2 , Vth 3 , etc.) in all the memories. This average may be based on an anticipated average usage profile for the industry, or may be based on simple assumptions about voltage drift, but all the memories are manufactured with the same set of reference voltages, based on this average profile. If the actual usage profile for particular group of memories is different than this average profile, the actual memory cells may drift in a different direction/amount than predicted, and one of the voltage states may fail much sooner than predicted.
FIG. 4 a shows the leakage curves for a single-state memory in which the actual leakage curves P(actual) and E(actual) are different than the predicted leakage curves P(pred) and E(pred) that were used to set the level of Vth when the memory was manufactured. As a result, the erased state, and the memory, experiences a failure earlier than expected, failing at time T(actual) rather than at the predicted time T(pred). This difference may be as much as several years, greatly shortening the life of the memory product.
In various embodiments of the invention, a customized usage profile based on anticipated usage conditions can be used to calculate the predicted usage curves. For example, different equipment makers may use different bias voltage to bias the flash memories. A flash memory used to store telephone numbers in a cell phone may see many more erase/program cycles than the BIOS in a personal computer. A flash memory in an automobile may see greater temperature extremes than one in an office product. Each of these examples produces a different application-specific usage profile that results in different leakage curves, and the memories manufactured for each can use different reference voltages. The memories manufactured for an application that produces a particular usage profile can be made using predicted leakage curves that are based on this particular usage profile. Based on this, the point at which the customized curves for E(cust) and P(cust) meet can be used to set the Vth threshold for that group of memories. FIG. 4 b shows how the custom-predicted curves P(cust) and E(cust) differ from the conventionally predicted curves P(pred) and E(pred). The threshold voltage Vth(cust) that is programmed into the reference cell can then be set to match the point at which P(cust) and E(cust) meet each other in FIG. 4 b , rather than at the conventional predicted threshold voltage Vth(pred). Vth(cust) can be the point at which the operational lifetime of the memory will be maximized, since any other level of Vth will intersect either the P(cust) or E(cust) curve at an earlier time, resulting in earlier failure of the memory.
Although the illustrations of FIGS. 4 a and 4 b are based on single-state memory cells, other embodiments can use the same principles to determine the set-points for multiple thresholds in multi-state memory cells. FIG. 5 shows custom, or application-specific, usage curves for a multi-state memory, in which E(cust), P 1 (cust), P 2 (cust), and P 3 (cust) have all been calculated based on the anticipated usage profile for a given application. Each threshold value can be individually determined by considering the leakage curve that approaches that threshold value over time. However, this may not be the only consideration. The expected time-to-failure of the memory will be the earliest time at which any of the leakage curves reaches any threshold value, since a failure to correctly read any state results in a failure of the cell and may effectively result in a failure of the entire memory. Care should be exercised to insure that the threshold value for one state does not overlap the starting point of the leakage curve for another state. FIG. 6 shows an embodiment in which threshold values are set by applying a ‘guard band’ between each curve and its bordering threshold value. This may be necessary because process variations and measurement inaccuracies can create a certain amount of uncertainty between the desired values and the actual values that are manufactured into the memories. The guard bands permit these uncertainties to occur without the danger that they will cause a threshold value and a programmed or erased state to unintentionally overlap, creating an immediate failure. FIG. 6 illustrates the principle by showing how P 1 , P 2 , and Vth 2 (cust) can be related. Ideally, Vth 2 (cust) can be selected to maximize the length of time that passes before P 2 intersects Vth 2 (cust) and causes a memory failure. However, in some embodiments, the initial starting point for P 1 (cust) is also separated from Vth 2 (cust) by a predefined amount so that process variations and/or measurement inaccuracies will not inadvertently cause an overlap between P 1 (cust) and Vth 2 (cust), which would result in an immediate failure when programmed state P 1 was read incorrectly as programmed state P 2 . This separation amount is the guard band, which can be determined by known techniques.
FIG. 7 shows a flow chart of a method embodiment. At block 71 , a leakage curve for the erased state is predicted, based on the application-specific usage profile. This usage profile can be based on the expected bias voltages, operating temperatures, erase/program cycles, materials technology, array size, and other factors that are specific to the application that is expected for the particular memory. At blocks 72 and 73 , application-specific leakage curves are similarly predicted for first and second programmed states. This assumes two programmed states. The method for a single programmed state would eliminate block 73 , while the method for additional programmed states would add blocks to predict those additional programmed states. Although each leakage curve is shown as a separate prediction, an integrated prediction algorithm can also be employed to interactively predict all the necessary leakage curves. At block 74 , a reference value is determined, based on the aforementioned leakage curves, that will maximize the predicted time-to-failure of the memory by maximizing the shortest of the erased state time-to-failure and the first programmed state time-to-failure. If a second programmed state is to be used, a second reference value is determined at block 75 that will maximize the predicted time-to-failure of the memory by maximizing the shortest of the first programmed state time-to-failure and the second programmed state time-to-failure. At blocks 76 and 77 , the reference values are programmed into reference cells in the memory. As before, the number of reference cells will depend on the number of states to be programmed into the addressable memory cells, and the flow chart of FIG. 7 can be adjusted as needed.
FIG. 8 shows a logic diagram of a memory 89 . Transistors 85 - 1 through 85 - x represent the addressable cells of the memory, which can number between a few cells and a few million cells, depending on the memory. Various embodiments of the memory can include flash memory, ferro-electric memory, dynamic random access memory, and other memory technologies. Each cell can be placed in the erased state or in one of the programmed states to represent the particular logic state desired. Address logic 82 can permit individual cells to be addressed for a read operation, while transistor 84 can be turned on to pass the detected voltage or current from the addressed cell to compare logic 81 . Transistors 86 - 1 through 86 - n represent the reference cells, with each one being charged to its predetermined threshold value. For a single-state memory embodiment, there may be one reference cell, while for a multi-state memory embodiment, there may be two or more such reference cells. Reference logic 83 can select one of the reference cells for comparison with the addressed memory cell, while transistor 87 can pass on the voltage or current from the selected reference cell to compare logic 81 , which can compare the value from the addressed memory cell with that of the selected reference cell. In the illustrated embodiment, each reference cell can be selected in turn so that the state of the addressed memory cell can be determined by sequentially comparing it with each reference cell. In another embodiment, the addressed memory cell can be compared with all reference cells simultaneously by providing multiple comparison circuits in parallel in compare logic 81 . Regardless of the approach used, when the comparison is finished, compare logic 81 can assert one of outputs E, P 1 . . . Pn to indicate which memory state the addressed memory cell is in. For a single-state memory, there may be one P output from compare logic 81 , while for a multi-state memory there may be two or more P outputs. In another embodiment, the output of compare logic 81 can be a binary number representing the detected state. Alternate embodiments may have multiple erased states.
Reference cells 86 - 1 through 86 - n can each be programmed to maximize the predicted time-to-failure of the memory, based on application-specific usage profiles for the application into which the memory is expected to be placed. Memory 89 can also be part of a system 80 , which includes processor 88 .
Since the threshold values in the reference cells can be easily customized with the embodiments described herein, different types of memory can be placed on the same integrated circuit die, or in the same multi-chip module, with similar reference cells being provided for each, but programmed to different levels to accommodate the different characteristics and usage profiles of the different memory types.
Various embodiments of the invention can include an apparatus, a system, a method, and a product made from the process method.
The foregoing description is intended to be illustrative and not limiting. For example, the erased state in the description can be referred to as another programmed state. Such differences in labeling would be obvious to a person of ordinary skill in the art and are intended to be included in the embodiments of the invention. Other variations will also occur to those of skill in the art. Those variations are intended to be included in the invention, which is limited only by the spirit and scope of the appended claims. | Programming a reference voltage in a reference cell of a charge-based memory to a level that will maximize the predicted operational life of the memory, based on the application-specific predicted usage profile of the memory and the effects of that usage profile on the leakage curves of the various memory states. The different states of a memory cell may have different leakage rates, based on operational and environmental considerations, causing the cell to fail prematurely in one state, while having significant remaining life in the other state(s). The operational life of the memory can be increased by adjusting the reference threshold voltage so that the faster-leaking sate will last longer before failure occurs. Maximum operational life can be achieved by setting the reference voltage to maximize the predicted time-to-failure of the state with the shortest predicted time-to-failure. | 6 |
BACKGROUND OF THE INVENTION AND PRIOR ART
This invention relates generally to the handling and disposal of hazardous materials, and more particularly to the treatment and cleaning-up of hazardous material spills.
Hundreds of millions of tons of hazardous materials are moved throughout the United States of highways and railroads. The consequences are severe whenever an accident of any kind causes a spill of these materials. In recent years, increased production, and resulting transportation, of these hazardous materials have increased the number of accidental spills. Accidental spills have become a growing problem for every industry in terms of staggering clean-up costs, and the long and short term costs to the environment and to humans.
Hazardous materials have been classified by the Environmental Protection Agency on the basis of ignitability, corrosivity, reactivity, and toxicity. Federal and local regulatory agencies require safeguards to be used in the handling of materials classified as hazardous.
Unlike a spill at a fixed site, such as a manufacturing facility, where the constant presence of hazardous materials and the potential for an accident are everyday facts of life, a transportation spill can occur almost anywhere at any time. Known techniques for the clean-up of transportation spills of hazardous material generally have involved either the flushing away of the material, which can cause considerable environmental damage, or in the isolation of the material by the use of an absorbent or similar material. The actual removal is commonly done by manual techniques using brushes, scoops, shovels and the like. These techniques are very inefficient and require large amounts of properly trained personnel, which skilled labor is not always readily available. A primary drawback of using absorbent materials, and the like, is that these materials add considerably to the quantity of material to be subsequently disposed of in a manner required by regulatory agencies. This increase in quantity substantially adds to the cost of disposal. Another problem encountered with the use of absorbent materials is that the absorption process is reversible, which does not comply with recent changes in regulations governing hazardous waste disposal.
U.S. Pat. No. 4,194,978, issued Mar. 25, 1980, to E. Crema, discloses a method and apparatus for removing solid and/or liquid matter containing harmful substances from the ground or other surfaces. In this arrangement, water is circulated onto the hazardous material for diluting same and is then drawn up by a vacuum arrangement into a holding tank on an associated vehicle. The recovered hazardous material is separated from the circulating water. This technique is very limited in applicability, since each hazardous material must be treated in a precise manner to comply with applicable regulations, and to assure the most efficient disposal of the waste.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a technique for on-site identification and treatment of hazardous materials involved in a transportation spill, and the like.
It is another object of the present invention to provide an efficient technique permitting the treatment, removal and disposal of spilled hazardous materials.
Still another object of the present invention is to provide mobile equipment for permitting the on-site identification, treatment and removal of spilled hazardous materials more safely and efficiently than known techniques for this purpose.
These and other objects are achieved according to the present invention by testing the material to be treated at the site of the spill, and measuring preselected chemical and physical properties of the material for the purpose of classification. Once properties have been measured and a suitable classification made, a response procedure for treating the material at the spill site is selected as a function of the properties that were measured so as to permit efficient treatment and, if necessary, removal of the spilled hazardous material.
The selected response procedure for treating the spilled hazardous material may require application of suitable treatment agents prior to, simultaneously with, or subsequent to removal of the spilled hazardous material from the spill site. Suitable treating reagents as well as steam, hot air, activated carbon and the like are transported to the spill site as part of the mobile apparatus for selective application as needed.
Should the selected response procedure include removal of the spilled hazardous material from the spill site, such removal is accomplished by drawing the material up through a suitable vacuum pump and depositing it into a holding tank, or other suitable storage container located on, or adjacent to the present invention.
Another advantage of the present invention is that it can be sent in response to hazardous material spills at remote locations, without needing large numbers of personnel for its operation.
This versatility allows the present invention to treat spilled hazardous materials in the most efficient and safest manner as selected for a particular spill, and in compliance with applicable laws and regulations.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a diagrammatic, top view, showing apparatus for treating a hazardous material spill according to the present invention;
FIG. 2 is a diagrammatic, side-elevation view of the apparatus illustrated in FIG. 1;
FIG. 3 is a diagrammatic, bottom plan view showing a pick-up head used with the apparatus illustrated in FIG. 1; and
FIG. 4 is a diagrammatic, transverse sectional view taken generally along the line 4--4 of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now more particularly to FIGS. 1 through 4 of the drawings, a spill treatment apparatus 10, also referred to herein as a spill responder system, permits treatment of spilled hazardous materials m by use of a mobile vehicle 12 arrangeable adjacent a spill of hazardous material m. Vehicle 12 can be of any suitable construction and may be supported on wheels, tracks, skids or even on a barge or other floating vehicle since the apparatus is also considered useful for treatment of spills in a body of water.
The spill responder system 10 as shown in FIG. 2 comprises a mobile vehicle 12 provided with a hydraulically operable boom assembly 14 comprising a main boom 16, and an auxiliary boom 18 hingedly connected to main boom 16 in a suitable manner for pivotal movement with respect to boom 16. Main boom 16 is secured to apparatus 10 by a swivel joint 20 having a horizontal axis permitting approximately 90 degrees of vertical movement of boom 16 and approximately 180 degrees of movement about a vertical axis, not shown. Conventional hydraulic actuator units 21 are provided for horizontally and vertically manipulating the boom assembly 14 from a control center 22 aboard the vehicle 12. This arrangement permits the pickup head 24 to be used on vertical walls, sloping ground and the like.
The pickup head 24 as shown in FIGS. 3 and 4 is mounted on the end of auxiliary boom 18 for pivotal movement in order to permit the position of the pickup head 24 to be adjusted relative to the associated vehicle 12 within the range of movement shown by the broken lines in FIG. 2. Pick-up head 24 is comprised of a rigid preferably rectangular frame 26. A peripherally extending suction conduit 28 having a plurality of spaced longitudinally extending openings 30 therein is mounted on the inner edges of frame 26 for picking up solid or liquid samples of the spilled hazardous material from near the edges of the pickup head 24. Also mounted on pickup head 24 at any convenient location preferably outside the boundaries of the frame 26 is a hazardous material discharge nozzle 32 for returning samples of tested hazardous materials to the spill site.
As seen in FIG. 3, pickup head 24 is also provided with cross braces 36 in the interior thereof for mounting a plurality of chemical treatment agent discharge nozzles 40 and steam or hot air nozzles 50 thereon. The particular arrangement of the discharge nozzles 40, 50 is not believed particularly important; however since steam, hot air and/or chemical reagents will be discharged into the waste spill at pressures high enough to provide substantial mixing, the discharge nozzles 40 and 50 should be spaced a sufficient distance interiorly from the edges of frame 26 so as to generally prevent turbulent conditions in the region of discharge inside of the pickup head 24 from extending outside the pickup head 24.
Suction conduit 28 extends from the pickup head 24 along the boom assembly 14 as shown to a sample collection vacuum pump 60 aboard vehicle 12.
Also shown is a pyramid shaped gas collection hood 70 affixed to pickup head 24 and having a discharge outlet 72 at its apex for the evacuation of gases collected in hood 70 via a conduit 74 which extends along the boom assembly 14 to a gas collection pump 76 aboard vehicle 12. Pickup head 24 is pivotally connected to auxiliary boom 18 at joint 25 and is pivoted with respect thereto by a conventional hydraulic actuator unit.
A holding tank 80 aboard vehicle 12 receives the discharge of gas collection vacuum pump 76 and preferably has mounted therein a chilling apparatus 82 for condensing the moisture content of gas discharged by pump 76 which collects in holding tank 80 and which will contain a substantial proportion of volatile hydrocarbons, if any, present in the gas. Also mounted in holding tank 80 is a gas filter 84, preferably a regenerable activated carbon filter, for filtering remaining harmful contents from the uncondensed gas collected from hood 70 which then may safely be discharged to atmosphere at vent 86.
Liquid or dry treatment reagents are preferably applied directly to the spill by nozzles 40 rather than being mixed with spilled hazardous material aboard vehicle 12 although it is contemplated that mixing could take place aboard the vehicle by conducting chemical reagents from on board sources 42 via a remotely controlled valved branch conduit 47 to the inlet side of a static mixer 62 arranged at the discharge side of sample collection vacuum pump 60. Chemical reagents are conducted from the sources 42 thereof to nozzles 40 by a reagent pump 44 and conduit 46. The pump pressure is selected to ensure that the discharge pressure at the nozzles 40 is adequate to ensure intimate mixing of the reagent with the spilled hazardous material. Remote controllable valves 48a-48d at the locations shown in the reagent conduit 46 enable automatic controls or a human operator to select which reagent to use dependent upon the character of the spilled hazardous material and the routing of reagent directly through conduit 46 to the spill or through branch conduit 47 to static mixer 62.
The static mixer 62 receives the discharge of sample collection vacuum pump 60 to homogenize the contents of conduit 28 before the sampled materials are returned to the spill site by sample return conduit 64 which is routed back along the boom assembly to the hazardous material discharge nozzle 32.
An important feature of the invention is its capability of immediately determining the characteristics of the spilled material in the field and of monitoring the progress of the treatment as heated fluids or chemical reagents are applied to the spill. At the minimum, the apparatus is provided with pH and oxidation reduction potential (ORP) probes 90, 92 at suitable locations in conduit 64 at the output of static mixer 62 and preferably also on the pickup head 24 so that the sampled materials conducted aboard the apparatus in conduit 28 may be accurately determined.
A central controller unit 100 is located in the control central 22 aboard vehicle 12. The controller unit 100 comprises pH and oxidation reduction potential (ORP) analyzers and a flame ionization detector (FID) for continuously monitoring data electronically transmitted from the probes 90, 92. Central controller unit 100 therefore provides analytical data which may be displayed in control center 22 to enable a human operator to actuate selected remote controllable valves 48 as desired or this process can be completely automated by the use of computer techniques.
If the probes 90, 92 and central controller unit 100 detect the presence of volatile hydrocarbons in the spill, heat in the form of steam or hot air produced from an on board boiler 52 is discharged from the steam nozzles 50 on the pickup head 24 directly onto the spilled materials. The above mentioned vacuum pump 76 is then actuated to remove hydrocarbons volatilized by the injection of steam underneath the pickup head 24 and hood 70.
It will be appreciated by those skilled in the art that additional probes 90, 92 may be mounted on pickup head 22, in holding tank 80 near vent 86 and in other locations as desired to permit more accurate sensing and identification of the preselected physical and chemical characteristics such as pH, oxidation reduction potential (ORP) and temperature of hazardous material m in a known manner. One example of analyzing equipment suitable for use with system 10 as a gas analyzer is a conventional flame ionization detector can be employed as a hydrocarbon analyzer, one suitable example being Model No. RS 100 manufactured by Ratfisch Instruments of Garden Grove, Ca.
Preferably, the pickup head 24 should be maintained at a substantially constant distance from the spill. Accordingly, a proximity sensor or sensors 110 may be mounted in the vicinity of the pickup head 24 with automatic warning signals being transmitted to the control center 22 if the operator inadvertently allows the pickup head 24 to deviate from preselected distance limits.
For safety purposes at least one thermocouple 112 is provided on the pickup head 24 in order to measure, in a conventional manner, the temperature of hazardous material m particularly while same is being treated. Various reagents used in treating certain hazardous materials can cause exothermic reactions, and as a result it is important that the temperature of these hazardous materials be monitored in order to make certain that, for example, the flash point of the materials is not reached. The out put of the thermocouple 112 is transmitted to the control center 22 for display on a control panel.
Finally, it will be appreciated by those skilled in the art that one or more auxiliary vehicles (not shown) or hand held vacuums (not shown) can be connected to mobile vehicle 12 and arranged for drawing hazardous material m aboard vehicle 12.
In operation, the spill responder system 10 according to the present invention treats spilled hazardous materials by first measuring as by the probes 90, 92 properties of hazardous material m, such as oxidation reduction potential, pH, temperature and the like. Based on the properties measured an appropriate procedure or plan is selected for treating the spilled hazardous material m.
If this procedure calls for applying a treating agent, or for volatizing hazardous material m, either prior to or simultaneously with removal of material m from the spill site, the appropriate reagent or heated medium is fed through the nozzles 40, 50 and onto the spill.
At any time during the treatment process particularly hazardous or difficult to treat material m may be drawn from the spill site and routed to holding tank 80 by remotely controllable valve 65 and associated branch conduit to tank 80. When holding tank 80 is full, the overflow can either by drawn off through discharge port 87 to an auxiliary holding tank, or mobile vehicle 12 can be taken to an appropriate disposal facility.
A wide variety of reagents are usable with a system 10 according to the present invention including neutralizers, dispersants, emulsifiers, oxidizers, absorption solidifiers, and the like. If the spilled hazardous material m is an acid or a caustic, for example, the pH is first brought into a range from 5 to 9 and the spill may be solidified as appropriate. Volatilized organics are separated from remaining air within the holding tank by the chilling apparatus 82 or the contents of gas conduit 74 may be conducted directly to filter 84. Other hazardous materials are neutralized, oxidized or solidified as appropriate.
Solidifiers must involve either chemical transformation or encapsulation in the nature of an irreversible process. If petroleum hydrocarbons, solvents, and other liquid synthetic chemicals, are involved, the CdF Chimie Company of Paris has developed an agent sold under the trade name "Norsorex Ap" which is effective in treating these materials. If the material m is an aromatic, amine, aldehyde, or a chlorinated solvent or ester, a solvent solidifier such as that sold under the trade name Spill-X by Ansul Corporation of Marionette, Wis. can chemically transform the liquid material into a pliable mass that exceeds current regulations.
Persons skilled in the art will readily appreciate that various modifications can be made from the preferred embodiment of the invention disclosed above thus the scope of protection is intended to be defined only by the limitations of the appended claims. | Spills of hazardous materials are treated at the site of the spill using an integrated spill responder system which enables personnel to remain at a safe distance from the spill. The mobile, fully self-contained system is dispatched to the spill site and uses a remotely controlled spill treatment head which is maintained in close non-contact proximity to the spill. The system continuously monitors the progress of the treatment operation through various sensors mounted on a boom assembly, or by vacuum drawing samples of the spilled material and chemical treatment agents mixed therewith aboard the spill responder vehicle. Once the spill has been reduced to a non-hazardous form, the treated material can be left at the site of the spill, removed by standard vacuum trucks, or removed by the spill responder system itself by using internal storage tanks. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to a filter cap for the hygienic preparation of a nutritional composition, especially an infant/toddler formula. More particularly, the invention relates to a filter cap for being connected to a container containing a predefined amount of nutritional formula base for the preparation of a ready-to-drink aqueous nutritional formula composition in combination with supplied liquid.
BACKGROUND OF THE INVENTION
[0002] Nutritional formulas or compositions can be, for instance, infant formulas or also nutritional liquids for toddlers, invalids, elderly people, humans having nutritional deficiencies and/or having a deficient immune system or athletes.
[0003] In the field of nutritional compositions, single-serving solutions are known which enable to provide a predefined amount of comestible product to a consumer.
[0004] WO2009/083495 for example relates to a packaging for a consumable articles such as a comestible product or medicine, that comprises a container including an amount of the consumable article necessary for a single use, wherein the container is provided at one end thereof with an opening being surrounded by a rigid skirt adapted for being connected to a liquid container such as a bottle. Opening means of the container enable to mix the consumable article of the container with liquid provided within the bottle.
[0005] A more convenient preparation of a nutritional composition is enabled by a preparation device in which a single-serving of a preferably powdered composition being provided within a capsule or cartridge is dissolved by means of injection with filtered respectively sanitized liquid such as water. Thereby, any undesired contaminants should be removed from the liquid before the liquid is mixed with the ingredients. For this purpose, such a device preferably comprises filter means for filtering respectively sanitizing the water.
[0006] In recent development, capsules with integrated antimicrobial filter have been introduced into the market in order to ensure the provision of filtered respectively sanitized liquid to the capsule for the preparation of the nutritional composition.
[0007] US2011233119A1 relates to a sports bottle device with filter isolated from filtered fluid and may have particular application for baby formulas. The device comprises a lower filtering bottle section for connecting to an upper bottle delivery section. However, such lower filtering bottle section is not formed as a cap for connecting to a feeding container. It is furthermore not adapted to be connected to external liquid dispensing means for being supplied with liquid by these means. In particular, the lower filtering section must be disconnected from the upper bottle section before being fed with liquid such as from a water supplying tap. Furthermore, the filter assembly is not arranged in the lower filtering section to remove contaminants from liquid supplied into the feeding container through the inlet means by the external liquid dispensing means. The filter assembly is configured to filter liquid when the liquid is transferred from the lower bottle section to the upper bottle section. As a result, the device lacks hygiene as the upper bottle section may be contaminated by the lower bottle section when the lower bottle section is connected to the upper bottle section after refilling of the lower bottle section. Furthermore, the device is not adapted to provide a good powder dissolution in liquid since the liquid is transferred from the lower bottle section to the upper bottle section by effect of pumping with the bellows provided in the lower bottle section thereby conferring potentially low energy to the liquid flow.
[0008] WO2009/092629A1 for example relates to a capsule for use in a beverage production device, the capsule containing ingredients for producing a nutritional liquid when a liquid is fed into the capsule at an inlet face thereof, the capsule being provided with an anti-microbial filter.
[0009] WO2010/128051A1 relates to a capsule for preparing a nutritional product including a filter adapted for removing contaminants wherein the filter is formed of a filter unit that comprises a filter membrane and an outlet wall for supporting the filter membrane; the outlet wall comprising at least one liquid outlet communicating with the container.
[0010] A drawback with the known capsule-based preparation devices comes from the fact that in addition to the capsules containing the infant formula base, a serving vessel for the instant formula such as a baby bottle is required. Accordingly, the required space for storage and transport of the components necessary for the preparation of the instant formula is relatively large.
[0011] Another drawback comes from the fact that the release of a reconstituted liquid composition from a capsule requires a complete dissolution or dispersion of the ingredients/formula with the diluents (e.g. ambient or warm water) to ensure a complete release of the resulting composition from the capsule to the serving bottle.
[0012] Another drawback remains the requirement for cleaning and sterilizing serving vessel that is to be carried out after each and/or before each preparation of the nutritional composition.
[0013] Therefore, a solution is sought-after which overcomes these problems.
[0014] In particular, it is desirable to enable a facilitated storage and transport of the components of the beverage preparation system. It is also desirable to reduce the number of these components and their volume in order to reduce the environmental impact of the packaging.
[0015] It is also an object to remove the need for cleaning respectively sterilization of any major component.
[0016] The present invention seeks to address the above-described problems. The invention also aims at other objects and particularly the solution of other problems as will appear in the rest of the present description.
Object and Summary of the Invention
[0017] In a first aspect, the present invention relates to a filter cap for filtering liquid, the filter cap comprising a liquid inlet means designed to be supplied with liquid from external liquid dispensing means, an adaptor for connecting the filter cap to the liquid dispensing means, connection means designed for selectively connecting an opening of the filter cap to a container designed to hold a powdered or concentrated liquid nutritional formula base for the preparation of the nutritional composition upon hydration with the supplied liquid, and a filter assembly in the flow path of the liquid from the inlet means to the opening, the filter assembly being configured to remove contaminants from liquid supplied into the container through the inlet means.
[0018] In particular, the liquid inlet means is arranged to supply liquid from an inlet face of the cap to the opening such that, when connected to the feeding container, liquid is fed from the external liquid dispensing means into the container. Therefore, the dissolution of the powdered or concentrated liquid nutritional formula base can be more effectively obtained since the energy provided by the flow can be obtained from the external liquid dispensing means and the liquid can be supplied in the form of a jet through the inlet opening into the container. Furthermore, there is no need for removing the cap from the container during liquid supply and dissolution of the nutritional formula is obtained as liquid is fed.
[0019] According to the present invention, a filter cap for filtering liquid provided to an interior of a container holding a concentrated liquid nutritional formula base is provided, whereby the filter cap may be independently provided and connected to any given container holding an amount of the formula base or may be assembled to a given container such as at a manufacturing site.
[0020] In the following application, the simplified terms “formula base” means a powdered or concentrated liquid nutritional formula base specifically designed for infants, toddlers, humans having nutritional deficiencies and/or having a deficient immune system, invalids, elderly people, or athletes; such formula base requiring a liquid, such as water, for the preparation of a ready-to-drink nutritional composition.
[0021] In a preferred mode, the filter cap comprises a body portion having a first side to which the filter assembly is connected and a second side in fluid communication with the first side, on which the opening is arranged. On said second side, the connection means of the filter cap are preferably integrally formed with the body portion. The connection means are preferably arranged annular to the opening. Thereby, the connection means may be a protruding connection skirt which is designed to match a standard screw threat of a bottle such as e.g. a baby bottle.
[0022] In a preferred embodiment, the filter cap further comprises liquid outlet means that are designed to release gas and/or liquid from the container connected to the filter cap to the exterior of the filter cap.
[0023] The liquid outlet means may for example be constituted by an aperture or opening in the body portion of the filter cap and connected at least to the opening provided on the second side of the filter cap. Thereby, the liquid outlet means are preferably extending from the second side to the first side of the body portion of the filter cap.
[0024] In an alternative embodiment, the outlet means are designed to provide an additional flow path for liquid from the container connected to the filter cap respectively from the opening on the second side of the body portion in fluid connection with the container to the exterior of the filter cap.
[0025] Thereby, said additional flow path is preferably different from the flow path from the inlet means to the opening.
[0026] The additional flow path is preferably arranged in series or in parallel to the flow path from the inlet means to the opening.
[0027] The filter cap preferably further comprises a gas-liquid equilibrium means to allow gas, e.g., air or a protective gas contained in the container connected to the filter cap, to leave the container as liquid is fed thereto through the filter means. In a mode, the gas-liquid equilibrium means may be a one-way valve which is permeable to gas but impermeable to liquid, thereby allowing the exit of gas from the interior of the container when water is fed thereto. Such gas-liquid equilibrium means may, for example, be constituted by a venting membrane connected or integrally formed with the body portion of the filter cap to equalize the pressure within the container when liquid is provided to the container by means of the filter cap.
[0028] The gas-liquid equilibrium means may as well be arranged in the flow path from the inlet to the opening of the body portion or the additional flow path from the opening to the outlet means.
[0029] In a preferred embodiment, the liquid inlet means are designed to be connected by an external liquid probe of the liquid dispensing means. Accordingly, provided liquid such as preheated water can be directly fed to the inlet means and thus to the interior of a container connected to the filter cap in order to prepare the nutritional composition.
[0030] In a preferred mode, the filter assembly according to the present invention is designed to be selectively removed from the filter cap.
[0031] Thereby, the filter assembly is preferably removably connected to the body portion of the filter cap. In particular, the filter cap may comprise a disposable portion fixedly connected to at least the filter assembly and removably connected to the body portion.
[0032] The filter assembly comprises a filtering membrane and at least one rigid supporting wall downstream of the membrane. Preferably, the membrane is placed between a rigid upper (i.e. upstream) and lower (i.e. downstream) supporting wall. The micro-porous membrane is arranged to form a barrier to contaminants, in particular, microorganisms such as bacteria. For antimicrobial purpose, the filter membrane has preferably a pore size of less than 0.4 microns, most preferably of less than 0.2 microns. It may have a thickness of less than 500 microns, preferably between 10 and 300 microns. The material of the membrane can be chosen from the list consisting of PES (polyethersulfone), cellulose acetate, cellulose nitrate, polyamide and combinations thereof. Thereby, the outer wall of the filter assembly preferably comprises a liquid inlet and the inner wall comprises a liquid outlet to direct at least one liquid jet into the container. The liquid inlet of the filter assembly is preferably designed to be connected to an outlet probe of the liquid dispensing means in order to provide liquid to the filter assembly and thus, to the interior of the container.
[0033] The filter assembly is preferably designed as a handleable rigid unit to withstand the pressure exerted thereon by liquid fed in the container and also to resist to manual mechanical constraints such as squeezing or piercing of the membrane by the outlet probe of the dispensing device.
[0034] The filter assembly according to the present invention may be designed as the filter unit described e.g. in WO 2010/128051.
[0035] The filter cap preferably further comprises a resealable portion arranged in the flow path of the liquid from the inlet means to the opening. Thereby, the resealable portion is preferably designed to close-off the flow path between the inlet means and the opening after provision of liquid by the external liquid dispensing means.
[0036] Hence, during feeding of the prepared nutritional formula from the container to the outlet means of the filter cap, liquid is prevented from bypassing the outlet means of the filter cap and thus, the serving of the complete nutritional formula to the human is ensured.
[0037] According to a preferred mode, the resealable portion is designed to interact with the disposable portion of the filter cap to close-off the flow path from the opening to the liquid inlet upon removal of the disposable portion. Thereby, the resealable portion may be designed to elastically and/or plastically deform in order to close-off said flow path.
[0038] In another preferred embodiment of the present invention, the filter cap further comprises feeding means such as a teat or nipple assembly.
[0039] Thereby, the teat assembly may be provided as an additional part to the filter cap which may be connected to the filter cap by means of additional connection means of the filter cap. Thereby, the teat assembly may be designed to match with a correspondingly shaped connection means. The connection means may also be designed to fit a standard teat available on the market.
[0040] Accordingly, the user may provide an external teat assembly to the filter cap in order to facilitate feeding of the nutritional composition from the container to the consumer.
[0041] Thereby, the connection means are preferably arranged in the vicinity of the outlet means of the filter cap and designed to enable a stable connection of the filter cap with the nipple assembly.
[0042] Alternatively, the filter cap may comprise an integrally formed feeding means respectively a teat assembly which is arranged in fluid communication to the opening of the filter cap. The teat assembly may be connected to the outlet means or may constitute the outlet means of the filter cap.
[0043] Thereby, the integrally formed teat assembly is preferably connected to the body portion of the filter cap. The integrally formed teat assembly may as well be designed to be selectively removable from the body portion of the filter cap.
[0044] In a preferred embodiment of the invention, the filter cap further comprises sealing means such as a sealing membrane or sealing cap that is arranged to cover the first inlet side of the filter cap, and in particular the liquid inlet in order to prevent ingress of contaminants before use. Preferably, when the filled cap is a separate part of the container, a sealing membrane or cap is also arranged to cover the second outlet side.
[0045] In a preferred embodiment, the outer wall of the filter assembly is preferably covered by a puncturable membrane made of polymer and/or aluminium to enable liquid to be supplied to the filter assembly by means of a liquid outlet probe of the liquid dispensing means.
[0046] The sealing means may as well at least partially constitute the disposable portion of the filter cap which is removably connected to the body portion in order to remove the filter assembly from the body portion of the filter cap. Thereby, at least a portion of the sealing means may be fixedly connected to the filter assembly and designed to allow a selective removal of the filter assembly from the body portion of the filter cap.
[0047] Therefore, the sealing means according to the present invention preferably comprise a first sealing membrane and a second sealing membrane with different respective sealing strength. Thereby, the second sealing membrane is at least partially fixedly connected to the filter assembly. Preferably, the sealing connection of said second membrane and the filter assembly is stronger than the sealing connection between the second membrane and a portion of the filter cap.
[0048] The filter cap preferably comprises a reinforcing structure for supporting the filter membrane within the body portion of the filter cap. Thereby the reinforcing structure may be a recession or protrusion formed within the filter cap. Moreover, the reinforcing structure may be a T-shaped, an X-shaped or a Y-shaped support which is preferably provided in the flow path from the filter membrane to the opening of the filter cap.
[0049] The reinforcing structure is preferably designed to support the filter membrane against pressure and/or force supplied from the exterior thereon. Moreover, the reinforcing structure is preferably positioned to abut the filter membrane and to prevent a displacement of the filter membrane towards the opening respectively towards a container connected to the filter cap. Such displacement could indeed damage the filter membrane, e.g., causing its breakage, and consequently would reduce the safety level of the device.
[0050] The adaptor of the filter cap is preferably designed to match with an additionally provided cap connector e.g. for connecting the filter cap to a liquid dispensing means. The adaptor can be one or more portions of wall protruding transversally or being recessed from an outer surface of the filter cap.
[0051] In another aspect, the present invention relates to a beverage production system, comprising a filter cap according to the present invention, a container or bottle designed to hold a powdered or concentrated liquid nutritional formula base for the preparation of the nutritional composition upon hydration with the supplied liquid, and a liquid dispensing means having: connection means for connecting to at least a portion of the filter cap and outlet means for supplying liquid to the filter cap.
[0052] Moreover, system according to the present invention preferably also comprises an additionally provided cap connector for connecting the inlet means of the filter cap to the outlet means of the liquid dispensing means.
BRIEF DESCRIPTION OF THE FIGURES
[0053] FIG. 1 a is a sectional side view of an embodiment of the filter cap according to the invention.
[0054] FIG. 1 b is a sectional side view of the filter cap according to FIG. 1 a , wherein a container or bottle has been connected to the filter cap.
[0055] FIG. 2 is a sectional side view of another embodiment of the filter cap according to the invention, wherein a container or bottle has been connected to the filter cap.
[0056] FIG. 3 is a sectional side view of an embodiment of the system according to the present invention, wherein the bottle is connected to the water dispensing means.
[0057] FIG. 4 is a sectional side view of a preferred embodiment of the system according to the present invention, wherein the filter cap is connected to the water dispensing means by means of a cap connector.
[0058] FIG. 5 a is a perspective top view of the embodiment according to FIG. 1 a in which an outer membrane is removed from the filter cap.
[0059] FIG. 5 b is a sectional side view of the embodiment according to FIG. 5 a , wherein the filter assembly is removed.
[0060] FIG. 5 c is sectional side view of the embodiment according to FIGS. 5 a and 5 b , wherein an additionally provided feeding assembly is attached onto the filter cap.
[0061] FIG. 6 a is a sectional side view of another embodiment of the filter cap according to the invention, wherein the filter cap comprises an integrally formed feeding means.
[0062] FIG. 6 b is a sectional side view of the embodiment according to FIG. 6 a , to wherein the filter cap is connected to a feeding container or bottle.
[0063] FIG. 7 a is a perspective side view of an assembly of a filter and bottle of the embodiment according to FIG. 6 b.
[0064] FIG. 7 b is a perspective side view of the embodiment according to FIG. 7 a , wherein the filter assembly has been removed from the base portion of the filter cap.
[0065] FIG. 7 c is a perspective side view of the embodiment according to FIGS. 6 a and 6 b , wherein the feeding assembly is in an extended ready-to-feed position.
[0066] FIG. 8 a is a sectional side view of the embodiment according to FIGS. 6 a and 6 b , wherein the filter cap is connected to a cap connector of the system.
[0067] FIG. 8 b is a perspective side view of the embodiment according to FIG. 8 a.
[0068] FIG. 9 a is a perspective side view of an injection head of water dispensing means and a cap connector.
[0069] FIG. 9 b relates to the embodiment according to FIG. 9 a , wherein the cap connector is inserted into the injection head.
[0070] FIG. 9 c shows the assembly according to FIG. 7 a being inserted into the injection head by means of the cap connector.
DETAILED DESCRIPTION OF EMBODIMENTS
[0071] FIG. 1 shows a sectional side view of a preferred embodiment of the filter cap 1 according to the present invention.
[0072] The filter cap 1 comprises a tubular body portion 17 that is preferably integrally formed with connection means 13 designed to connect the filter cap 1 to a feeding container or bottle 3 (see FIG. 1 b ).
[0073] The body portion 17 preferably comprises an opening 10 which is designed to contact to an inlet respectively outlet aperture 3 a of the feeding container 3 in order to establish a fluid connection between the container 3 and the body portion 17 .
[0074] The opening 10 preferably extends from a first end 17 a of the body portion 17 to a second end 17 b thereof, which is preferably arranged opposite to the first end 17 a.
[0075] The filter cap 1 further comprises a filter assembly 7 that is removably connected to the body portion 17 of the filter cap 1 . Thereby, the filter assembly 7 may be arranged within the opening 10 of the body portion 17 as shown in FIG. 1 a . The, the filter assembly 7 is arranged to at least partially close-off the opening 10 .
[0076] The filter assembly 7 is preferably held within the opening 10 by means of provided reinforcement structure 12 . The reinforcement structure 12 may be any structure integrally formed or provided within the filter cap 1 . In particular, the reinforcement structure 12 may be a protrusion and/or a recession integrally formed within the body portion 17 .
[0077] The filter cap 1 further comprises sealing means 9 a , 9 b , 9 c which prevent the ingress of the contaminants into the filter cap 1 before use thereof.
[0078] Thereby, the sealing means comprise at least one sealing membrane and/or cap, preferably sealing membranes 9 b , 9 c and a sealing cap 9 a which are arranged on a first and second sides 17 a , 17 b of the filter cap 1 and which may be sealed to an outer surface of the filter cap 1 . The outer sealing membranes 9 b , 9 c and cap 9 a are preferably designed to be removable by a user before use of the filter cap 1 . Instead of the outer sealing membranes and/or sealing cap the filter cap 1 may be provided in a sealing enclosure such as a removable sealing package.
[0079] The sealing means may also comprise an inner sealing membrane 9 b that is at least partially fixedly connected to the filter assembly 7 of the filter cap 1 . Thereby, the outer sealing means 9 a provided on the first side 17 b of the body portion 17 may as well be sealed to the inner sealing means 9 b in a manner to enable a facilitated removal of the outer sealing means 9 a by manual pulling force of a consumer.
[0080] The filter assembly 7 is in connection or comprises a liquid inlet 6 suitable for being connected by a specifically designed liquid probe 11 of a dedicated liquid dispensing means 20 (see FIG. 3 ).
[0081] The filter assembly 7 preferably comprises a filter membrane 7 a and a filter outlet 7 b which connects the liquid inlet 6 to the opening 10 of the bottle 1 . The filter membrane 7 a is situated in the liquid flow path between the inlet 6 and the filter outlet 7 b . The membrane is preferably a micro-porous membrane designed for removing any contaminants present in liquid provided to the filter assembly 7 .
[0082] The liquid inlet 6 is preferably sealed by the inner sealing means respectively the inner sealing membrane 9 b sealed to the filter assembly 7 . The inlet 6 may however also be sealed by means of a piercable material respectively sealing means integrally formed with the filter assembly 7 , such as e.g. plastic material designed to be pierced by on outlet probe 11 of the liquid dispensing means 20 .
[0083] The filter cap 1 further comprises outlet means 8 which enable the ejection of liquid and/or air from a container 3 (see FIG. 1 b ) connected to the filter cap 1 to the exterior of the filter cap 1 .
[0084] The outlet means 8 may be constituted by at least a portion of the opening 10 formed in the body portion 17 of the filter cap 1 .
[0085] According to the embodiment of FIGS. 1 a and 1 b , the opening 10 in the body portion 17 is not fully covered respectively closed-off by means of the filter assembly 7 and thus, during the injection of the liquid to the interior of a connected container 3 , air may be removed from the container 3 . For this purpose, the inner sealing means respectively sealing membrane 9 b preferably comprises a gas-liquid equilibrium means such as a venting opening 15 which allows the removal of internal gas from the container 3 as liquid is filled in the container through the liquid inlet and after the outer sealing means 9 a have been removed from the filter cap 1 .
[0086] As an alternative, the filter assembly 7 may comprise integrally formed gas-liquid equilibrium means (such as described later in conjunction with the mode of FIG. 2 ) such as for example a venting opening. Said integrally formed venting opening may be sealed by the provided sealing means 9 a . Thereby, the venting opening may be opened by a user, e.g. by removing the sealing means 9 a or by dedicated opening means provided at a liquid dispensing means 20 .
[0087] The filter cap 1 further comprises connection means such as an adaptor 2 which are designed to enable a connection of the filter cap 1 to a dedicated liquid dispensing means 20 or an additionally provided cap connector 25 , 25 a (as apparent in FIG. 4 ). The connection means 2 may be at least one protrusion and/or recession formed in the filter cap 1 . For example, the connection may be a bayonet-type connection or a thread.
[0088] FIG. 1 b shows a sectional side view of the embodiment according to FIG. 1 a , wherein the filter cap 1 is connected to a feeding container 3 such as a feeding bottle.
[0089] The container 3 has an opening 3 a in fluid connection with the opening 10 of the filter cap 1 and encloses a predefined portion of powdered or concentrated nutritional formula base 5 that has been provided by a user before assembling the filter cap 1 onto the feeding container or bottle 3 . Alternatively, the filter cap is assembled to a feeding container filled with a dose of powdered or concentrated nutritional formula base at a manufacturing site.
[0090] The connection means 13 for connecting the filter cap 1 with the container 3 is preferably a protruding skirt comprising an inner standard screw threat suitable for connecting to common feeding bottles such as standard baby bottles. The connection means 13 could as well be of special design to be assembled only to matching connection means of non-standard feeding bottles.
[0091] The connection means 13 may as well be adaptable such as e.g. an adaptable clamping means designed for being connected to different containers 3 respectively bottles of variable neck portions.
[0092] FIG. 2 shows a sectional side view of another embodiment of the filter cap 1 according to the invention. Thereby, the filter assembly 7 fully covers the opening 10 provided in the body portion 17 of the filter cap 1 .
[0093] The filter assembly 7 according to said embodiment comprises an integrally formed gas-liquid equilibrium means 8 a , such as for example a vent or air outlet channel or a valve, in order to allow gas to exit the container 3 during filling of the container with liquid provided from water dispensing means 20 when connected to the liquid inlet 6 . Therefore, the inner membrane 9 b comprises a venting aperture 15 which connects the gas-liquid equilibrium means 8 a of the filter assembly to the exterior of the filter cap 1 . It is to be noted that FIG. 2 refers to a state of the filter cap 1 , wherein the outer membrane or cap 9 a has already been removed by the user. Thereby, the inner membrane 9 b may comprise a protruding lip or tab 15 a in order to facilitate removal of the inner membrane 9 b from the filter cap 1 . The inner membrane 9 b is perforable by a probe of the water dispensing means through the liquid inlet 6 .
[0094] FIG. 3 shows a schematic drawing of the dispensing system according to the present invention comprising liquid dispensing means 20 and a filter cap 1 with a feeding container 3 connected thereto. The liquid dispensing means 20 preferably comprise a water reservoir 30 , a pump 40 and a heater 50 suitable for heating the liquid provided by means of the liquid supply in a continuous flow.
[0095] The liquid dispensing means 20 preferably further comprise connection means 20 a designed for connecting the adaptor 2 of the filter cap 1 .
[0096] Moreover, the liquid dispensing means 20 comprise an outlet probe 11 which is designed to connect to the inlet 6 of the filter assembly 7 of the bottle 1 .
[0097] In addition, the liquid dispensing means 20 may further comprise opening means 22 which are designed to tear or perforate the sealing membrane 9 a . Thereby, the opening means 22 may be arranged to open the membrane 9 a in order to allow venting of the container 3 during liquid injection thereof. Moreover, the opening means 22 may be integrally formed with the outlet probe 11 . The outlet probe 11 and/or the opening means 22 are preferably movable relative to the connection means 20 a of the dispensing means 20 . For example, the probe 11 and opening means 22 can be moved in a coordinated manner to provide each opening at the same time or sequentially.
[0098] After opening of the membrane 9 a by means of the outlet probe 11 and/or the opening means 22 , liquid may be injected into the filter cap 1 and thus, into container 3 . Thereby, a user may control the amount of liquid provided into the container 3 e.g. by means of a dedicated control means (not shown) connected at least to the pump 40 of the water dispensing means 20 . A dedicated control means suitable to provide a proper amount of water in the bottle may use a flow meter and a control unit as known per se.
[0099] FIG. 4 relates to another preferred embodiment according to the present invention, wherein the system further comprises a cap connector 25 which is designed to act as an interface between the water dispensing means 20 and the filter cap 1 . Thereby, the cap connector 25 preferably comprises connecting means 25 a for connecting to the adaptor 2 of the filter cap 1 , as well as connecting means 25 b being designed to connect the cap connection to the water dispensing means 20 .
[0100] The cap connector 25 may comprise an integrally formed liquid path 25 c connecting an inlet adapter 25 d at an inlet portion of the cap connector to an outlet probe 25 e at an outlet portion thereof. Thereby, the inlet adapter 25 d is designed to be connected to the outlet probe 11 . The outlet probe 25 e is designed to be connected to the inlet means 6 of the filter cap 1 .
[0101] FIG. 5 a relates to the filter cap 1 being at least partially opened by removing the first membrane or cap 9 a sealed to the outer portion of the second sealing membrane 9 b and/or the body portion 17 of the filter cap 1 . Thereby, an outlet aperture 15 or valve which is preferably provided within the membrane 9 b is laid open.
[0102] The liquid inlet 6 is preferably still covered by the inner membrane 9 b and is opened upon contact with the outlet probe 11 of the dispensing means 20 .
[0103] After the injection of liquid into the container 3 by means of the outlet probe 11 being connected to the filter assembly 7 , the filter assembly 7 may be removed from the filter cap 1 by tearing the second membrane 9 b as shown in FIG. 5 b (see arrow A). Thereby, the sealing between the second membrane 9 b and an outer circumferential portion 27 of the body portion 17 is weaker than the sealing connection between the second sealing membrane 9 b and the filter assembly 7 .
[0104] By removing the filter assembly 7 , a liquid outlet 8 b of increased cross-sectional area is provided which enables to facilitate the removal of the complete liquid nutritional composition 5 a from the container 3 .
[0105] Before the withdrawal of the nutritional composition 5 a , a feeding means such as a nipple or teat assembly 14 may be provided to the filter cap 1 . As can be seen in FIG. 5 c , the teat assembly 4 may be connected for example by means of a dedicated connection means such as a cap nut 32 which interacts with the provided screw thread 16 at the circumference of the body portion 17 or another connection means.
[0106] The teat assembly 14 may as well be specifically designed to match the screw thread respectively connection means 16 and/or an outer portion of the body portion 17 .
[0107] FIG. 6 a relates to another preferred embodiment of the filter cap 1 according to the invention, wherein the filter cap 1 comprises feeding means 14 a.
[0108] The filter cap 1 further comprises a disposable cap portion 19 which is connected to the body portion 17 of the filter cap 1 . Thereby, the disposable cap portion 19 forms preferably a sealing collar connected to an annular portion 17 c of the body portion 17 . The disposable portion 19 is preferably secured to the body portion 17 , e.g. by means of a removable latch member 19 a.
[0109] The filter assembly 7 is preferably fixedly connected to the disposable cap portion 19 which holds the filter assembly 7 in position above the feeding means 14 a by means of integrally formed reinforcement structure 12 a.
[0110] The feeding means 14 a is preferably a nipple or teat assembly which is connected to an inner annular surface 17 d of the body portion 17 , thereby preferably fully closing-off the opening 10 extending from a first side 17 a to a second side 17 b of the body portion 17 .
[0111] The integrally formed feeding means 14 a are preferably in a compressed respectively retracted state when the disposable cap portion 19 is connected to the body portion 17 . Thereby, the disposable cap portion 19 preferably at least partially covers the opening 10 on the first side 17 a of the body portion 17 in order to hold the feeding means 14 a in a retracted state as shown in FIG. 6 a.
[0112] The feeding means 14 a preferably constitute the outlet means of the filter cap 1 when the filter cap 1 is connected to a container or bottle 3 . Thereby, the feeding means 14 a comprise an outlet 8 c providing an additional outlet flow path from the opening 10 to the exterior of the filter cap 1 when liquid, e.g., nutritional composition, is dispensed from a connected container 3 .
[0113] The outlet 8 c preferably serves as a venting means in order to enable gas present in the container to exit the container 3 during provision of liquid thereto by means of the filter cap 1 .
[0114] The flow path from the inlet means 6 to the opening 10 which is used to fill the container 3 with liquid, in particular water, connected to the opening 10 is preferably arranged in parallel to the additional outlet flow path between the opening 10 and the outlet 8 c which is used to deliver the liquid nutritional composition.
[0115] Thereby, the disposable cap portion 19 preferably comprises an integrally formed liquid channel 6 b which is connected to the filter assembly 7 allowing flow communication between the inlet 6 and the opening 10 of the body portion 17 in order to constitute an inlet flow path for feeding liquid into the container 3 .
[0116] The filter cap 1 further comprises a resealable means 23 of the liquid channel 6 b.
[0117] The resealable means 23 is preferably formed by a tubular portion of the cap portion 19 holding open a resealable portion made of elastically deformable material comprising an aperture. In particular, the aperture of the resealable portion is held open by the tubular portion when the portion is inserted into the aperture and the aperture closes-off when the tubular portion is removed from the aperture such as when the cap portion 19 is removed from the body portion 17 of the cap. Thereby, the resealable portion 23 is preferably integrally formed with the feeding assembly respectively teat 14 a connected to the body portion 17 . The resealable portion may be formed on the border of the teat with the aperture traversing the border. The teat 14 a can, for instance, be formed of moulded silicone, elastomer or resilient and soft plastic.
[0118] FIG. 6 b shows the embodiment of the filter cap 1 according to FIG. 6 a in a state connected to a container respectively bottle 3 by means of the connection means 13 , wherein the bottle 3 is filled with a desired amount of nutritional formula base 5 and which may be designed expandable and/or retractable. Accordingly, the volume of the container 3 enclosed by an outer wall 30 of the bottle 3 is designed to be variable.
[0119] The bottle 3 may comprise an expandable and/or retractable portion 31 integrally formed with the outer wall 30 . The expandable and/or retractable portion 31 may be a concertina-like structure having a plurality of recesses and/or protrusions arranged about the circumference of the container 3 .
[0120] The bottle 3 may be stored in its retracted state as shown in FIG. 7 a . Thereby, the concertina-like portion 31 of the outer wall 30 is folded together in order to occupy a minimum storing space, but at the same time provides a sufficient volume for enabling the user to provide an amount of powdered or concentrated nutritional formula base 5 within the bottle 3 , sufficient to prepare the nutritional formula 5 a by injection of liquid into the filter cap 1 .
[0121] The concertina-like portion 31 of the bottle 3 may then be expanded as shown in FIG. 7 b either manually or by the liquid filling the bottle 3 during liquid provision to the filter cap 1 .
[0122] After the provision of liquid into the bottle 3 , the disposable portion 19 is removed from the body portion 17 by pulling the securing latch member 19 a.
[0123] The teat assembly 14 a that is preferably arranged within the filter cap 1 in a retracted state may then be brought into an extended state manually, e.g. by squeezing the bottle 3 (see FIG. 7 c ).
[0124] Instead of a bottle 3 having an expandable and/or retractable portion 31 , the system according to the present invention may as well comprise a expendable preform or a flexible, folded pouch that has a rigid rim portion to which the connection means 13 of the filter cap 1 may be connected. Thereby, the preform or pouch may be designed to automatically expand, respectively inflate or unfold during provision of liquid thereto by means of the filter cap 1 .
[0125] FIGS. 8 a and 8 b show the embodiment of the filter cap 1 according to FIGS. 6 a and 6 b , wherein the filter cap 1 is connected to a cap connector 26 that is designed for connecting the filter cap 1 to the dispensing means 20 and in particular to a dispensing head 30 a of the dispensing means 20 as also shown in FIGS. 9 a - 9 c.
[0126] The cap connector 26 preferably comprises a connecting portion 31 that connects to the adaptor 2 provided at a circumferential portion of the filter cap 1 . Thereby, the connecting portion 31 may be at least one guiding rail which interacts with the recessed or protruding adaptor 2 of the filter cap 1 (see FIG. 9 c , arrow C).
[0127] The connecting portion 31 may as well be designed as a snap-fit connection connecting to the adaptor 2 upon insertion of the filter cap 1 and/or turning of the filter cap 1 about a vertical axis thereof.
[0128] The cap connector 26 is preferably designed to be selectively connected to a receiving recess 34 of the dispensing head 30 a (see FIGS. 9 a and 9 b , arrow B). Thereby, the cap connector 26 may as well comprise an aperture 31 a for holding a cartridge or capsule containing a predefined amount of infant formula base, which is designed to receive the capsule when inserted from above in said aperture 31 a (see FIGS. 9 a - 9 c ).
[0129] The cap connector 26 preferably comprises integrally formed interface means 33 which are arranged to provide a signal transfer from the dispensing means 20 , to which the cap connector 26 is intended to be connected, to the filter cap 1 or vice versa. Thereby, the interface means 33 may be any means enabling the transfer of an optical, electrical and/or acoustical signal between the dispensing means
[0130] Preferably, the interface means 33 is a mirror arranged at the cap connector 26 such as to transfer or redirect a signal 35 from the dispensing means 20 towards an outer portion of the filter cap 1 . Thereby, the signal may be e.g. an optical signal 35 from a barcode reader 36 that is transferred by the interface means 33 of the cap connector 26 to a peripheral outer surface 19 b of the disposable portion 19 of the filter cap 1 onto which a barcode 37 may be provided.
[0131] It is to be understood that by means of the signal transferred from the filter cap 1 to the dispensing means 20 or vice versa, a dedicated control unit (not shown) of the dispensing means 20 may adjust the injection parameters such as the temperature, the flow rate and the amount of the liquid to be injected into the container or bottle 3 connected to the filter cap 1 .
[0132] Although the present invention has been described with reference to preferred embodiments thereof, many modifications and alternations may be made by a person having ordinary skill in the art without departing from the scope of this invention which is defined by the appended claims. | The invention relates to a filter cap ( 1 ) for filtering liquid and dispensing an aqueous nutritional composition to a human, the filter cap ( 1 ) comprising a liquid inlet means ( 6 ) designed to be supplied with liquid from external liquid dispensing means ( 20 ), an adaptor ( 2 ) for connecting the filter cap ( 1 ) to the liquid dispensing means ( 20 ), connection means ( 2 ) designed for selectively connecting an opening ( 10 ) of the filter cap ( 1 ) to a container ( 3 ) designed to hold a powdered or concentrated liquid nutritional formula base ( 5 ) for the preparation of the nutritional composition ( 5 a ) upon hydration with the supplied liquid, and a filter assembly ( 7 ) in the flow path of the liquid from the inlet means ( 6 ) to the opening ( 10 ), the filter assembly ( 7 ) being configured to remove contaminants from liquid fed into the container through the inlet means ( 6 ). | 0 |
RELATED APPLICATIONS
The present application is a continuation-in-part of application Ser. No. 852,291 filed Apr. 15, 1986, now abandoned.
The present application is related in subject matter to copending U.S. patent application Ser. No. 021,212 filed Mar. 3, 1987, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method of manufacturing a dehumidifier element for continuously obtaining dehumidified gas such as dry air by passing feed gas and desorbing gas alternately through the element. The element consists of a block with many small channels and having a solid adsorbent capable of reversibly adsorbing the humidity formed thereon.
2. Description of the Related Art
In our Japanese Patent Application No. 206849/1984, a method of manufacturing a humidity exchanger element including a dehumidifier element has been proposed, in which layered sheets of low density paper of inorganic fiber, such as ceramic fiber, are formed in a block with many small channels. The sheets or block are impregnated with water glass solution before or after the block-forming process and then heated and dried until the water glass solution is concentrated to hydrated water glass of 3-20% water content, after which the block is soaked in acid solution so that water glass and acid react to produce silica hydrogel. The block is thereafter washed and dried to obtain a strong element for a humidity exchanger consisting mainly of silica aerogel with the matrix of inorganic fiber paper. In this method, strong silica aerogel is stuck firmly to not only th surface of the inorganic fiber paper but also the apertures between the fibers of the paper, resulting in an element having greater physical strength and improved humidity adsorbing ability than would adhering powdered silica aerogel, which is available on the market, to inorganic fiber paper.
Aerogels providing humidity or gas adsorbing action include activated carbon, and adsorbents of the alumina-gel and silica-alumina-gel group.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method of manufacturing a dehumidifier element having improved durability and high efficiency, wherein, relying on the fact that adsorbents consisting of aerogels of metal silicates such as the above-mentioned aluminum silicate are easily produced by the reaction of water glass and a metal salt solution, such as aluminum salt, a strong honeycomb structure of metal silicate aerogel is formed on a porous sheet matrix of inorganic fiber.
In the present invention, a sheet of material of very low density paper (bulk density of not more than 0.5 g/cm 3 , and in the case of paper of 0.2 mm thickness, not more than 100 g/m 2 ), the main constituent of which is an inorganic fiber such as ceramic fiber, is prepared. A flat sheet and a corrugated sheet of this inorganic fiber paper are laminated alternately to form a block having many small channels.
To make the paper making easier, a small amount of organic fiber such as wood pulp or organic synthetic fibers is mixed in the inorganic fiber paper. The amount of the organic fiber used amounts only to several percent by weight of the total weight o the mixed fibers. During dehumidification of the dehumidifier element, the element will be subjected to a hot and less humid desorbing air having a temperature of 120°-180° C., which enters the element, at an inlet to regenerate the element. When this occurs, the above-referred organic fiber would be apt to burn and damage the element. To prevent such a problem, the sheet or the block is treated or fired with heated air of 200°-500° C. to remove organic substances from the paper. This step can be performed before or after forming the block from the flat sheets and the corrugated sheets of inorganic fiber paper. When the sheets are laminated with an inorganic adhesive such as water glass, the effect of firing before lamination is same as that after lamination; but when the sheets are laminated with an organic polymer adhesive such as polyvinyl acetate, epoxy resin and ethylene-vinyl acetate copolymer, the firing should be performed after the lamination to remove this organic adhesive as well as the other organic constituents.
The flat sheets and the corrugated sheets are impregnated with sodium silicate water glass solution and heated to dry so that the water glass solution is concentrated on the sheets. This can be performed before or after the laminating step. The laminated and water glass impregnated block is soaked in a metal sulphate solution, the solution selected from the group consisting of an aluminum sulphate solution and a magnesium sulphate solution. The reaction of the water glass and the metal sulphate produces metal silicate hydrogel without breaking the original form of the block. That is, the many small channels remain intact. Excess metal sulphate and metal silicate hydrogel not supported on the inorganic fiber paper are removed by washing the block. Then, the block is heated until dry to obtain a strong honeycomb-type element for a dehumidifier in which metal silicate aerogel, the main constituent, is firmly combined with the matrix of inorganic fiber paper.
In this method, the loss of water glass dissolved in the metal sulphate solution is prevented by heating the block after the impregnation of the block with water glass and before the impregnation of the block with metal sulphate solution. This concentrates the water glass solution, forming hydrated water glass or half-solid state water glass having 5-45% water content.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings show examples of the present invention.
FIG. 1 is a cross-sectional view of a device for carrying out the first process of the present invention;
FIG. 2 is a perspective view showing a first embodiment of a dehumidifier element formed according to the present invention;
FIGS. 3 and 7 are graphs showing a comparison of dehumidifying abilities between elements formed according to the present invention and those formed according to an existing method;
FIGS. 4 and 5 are graphs showing the dehumidifying abilities of the various elements formed according to the present invention;
FIG. 6 is a perspective view of a dehumidifier using the element illustrated in FIG. 2, a portion of the structure being broken away for the purpose of illustration;
FIG. 8 is a perspective view showing an example of a crossflow type element; and
FIG. 9 is a perspective view showing an example of a counterflow type element.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A pair of corrugated rollers 1 and 2 having desired teeth on the outer peripheries mesh with each other as shown in FIG. 1. A pressure roller 3 having a smooth cylindrical surface is urged against corrugated roller 2. Two adhesive applicators 4 and 5 include adhesive vessels 4a and 5a and adhesive applicator rollers 4b and 5b, respectively. The lower parts of adhesive applicator rollers 4b and 5b are dipped in an adhesive 6 stored in the respective adhesive vessels 4a and 5a. The main ingredient of the adhesive 6 is preferably water glass. The adhesive applicator roller 4b is mounted close to the corrugated roller 2.
Rolls of very porous papers 7 and 8 are provided. The papers 7 and 8 are made of ceramic fiber 70-90%, pulp 5-20% and binder 5-10%, and have a thickness of 0.1-0.5 mm and a density of not more than 0.5 g/cm 3 .
The paper 7 is applied between corrugated rollers 1 and 2 to form corrugated paper 7a. The corrugated paper 7a is supplied into the engaging portion of the corrugated roller 2 and the adhesive applicator roll 4b, and the adhesive 6 is applied to the ridged portion of the corrugated paper 7a. The corrugated paper 7a and the flat liner paper 8 are brought together between the corrugated roller 2 and the pressure roller 3 to obtain a single-faced corrugated sheet 9 by bonding the papers 7a and 8 together. The adhesive 6 is applied to the ridged portion of the single-faced corrugated sheet 9 by the applicator roller 5b of the adhesive applicator 5. By bonding and winding the glued corrugated sheet 9 around a shaft 10, a cylindrical honeycomb matrix 11 as shown in FIG. 2 having many small channels through both ends is fabricated.
The cylindrical honeycomb matrix 11 is treated or fired with heated air having a temperature of 200°-500° C. to remove organic substances in the paper and the adhesive.
The fired cylindrical honeycomb matrix 11 is soaked in a 20-35% aqueous solution of No. 1 water glass (silicon oxide 2.1: sodium oxide 1) and dried at 80°-100° C. for one hour. A honeycomb matrix having a hydrated or half-solid state water glass layer containing 5-45% water by weight and being 2-2.5 times the mass of the paper matrix is obtained. The honeycomb is soaked in 21% aqueous solution of aluminum sulphate with stirring, to produce aluminum silicate hydrogel on the paper. Sodium sulphate (a by-product), excess aluminum sulphate and aluminum silicate hydrogel not supported on the paper are removed by washing. By heating and drying the honeycomb, a dehumidifier element, the main constituent of the same being aluminum silicate aerogel, is obtained.
In the example mentioned above, after the cylindrical honeycomb matrix 11 is soaked in the aqueous water glass solution and heated to dry the water glass solution, it is soaked in the aluminum sulphate solution. As another example, fired ceramic fiber papers 7 and 8 are soaked in a water glass solution and dried to a suitable water content so that the surface becomes somewhat sticky before the corrugating process. In this process, a part of the somewhat sticky water glass can be used as the adhesive in the producing process of the single-faced corrugated sheet 9. This cylindrical honeycomb 11 is dried again and is soaked in an aluminum sulphate solution to produce aluminum silicate hydrogel.
Papers to be used for forming the matrix are inorganic fiber papers, the main constituent of which are not only the above-mentioned ceramic fiber, but also can be glass fiber, slag fiber, rock fiber, carbon fiber and mixtures thereof. Asbestos fibers are not preferable, because the asbestos fibers become fixed in lungs and prolonged exposure to asbestos fibers is known to cause lung cancer, a special swelling in the breast or at the peritoneum and/or asbestosis.
TABLE 1______________________________________WATER GLASS (Na.sub.2 O.nSiO.sub.2.xH.sub.2 O)(Japanese Industrial Standard) No. 1 No. 2 No. 3______________________________________Specific Gravity -- ≧54 ≧40(15° C. Be)SiO.sub.2 % 35-38 34-36 28-30Na.sub.2 O % 17-19 14-15 9-10Fe % ≦0.03 ≦0.03 ≦0.02Water-insoluble % ≦0.2 ≦0.2 ≦0.2______________________________________
As water soluble aluminum salts, aluminum sulphate, aluminum nitrate, primary aluminum phosphate and aluminum chloride are used, which can be easily obtained on the market at reasonable prices. Since water-soluble calcium salts and magnesium salts such as calcium nitrate, calcium chloride, magnesium sulphate and magnesium chloride, also react with water glass to produce silicate gels, the above-mentioned salts of Al, Ca and Mg were tried in the experiment.
FIG. 3 shows the equilibrium amounts of vapor adsorbed at a normal temperature (25° C.) by silica A gel, which is available on the market, and by the silicate gels of the present invention. Examples for comparison are produced by th reaction of hydrated water glass with 20% solution of aluminum sulphate, primary aluminum phosphate, aluminum nitrate, aluminum chloride, calcium nitrate, calcium chloride, magnesium sulphate and magnesium chloride heated at 60°-70° C. The equilibrium amounts of adsorbed vapor by these aerogels at a relative humidity of 75% are as shown in Table 2 below:
TABLE 2______________________________________using aluminum sulphate 37.6%silica A gel on the market 31.0%using primary aluminum phosphate 30.1%aluminum nitrate 23.7%magnesium sulphate 23.5%magnesium chloride 18.7%aluminum chloride 17.2%calcium nitrate 13.9%calcium chloride 13.0%______________________________________
Silica A gel is the general silica gel and has strong moisture-adsorbing ability. Silica B gel is a silica gel having low surface area, and adsorbs large amounts of moisture at high humidities.
Properties of silica A gel and of silica B gel on the market are shown in Table 3 below:
TABLE 3______________________________________ A gel B gel______________________________________Specific gravity 2.2-2.3 2.2-2.3Bulk density (kg/m.sup.3) 650-850 700-800Porosity 0.4-0.45 0.5-0.6Specific surface area 500-750 250-350(m.sup.2 /g)Mean pore diameter (Å) 20-30 50-60Moisture adsorbing rate (%)at relative humidity of20% 10-13 4-650% 25-30 7-1690% 34-40 40-75______________________________________
As indicated above and in FIG. 3, aluminum salts, except for aluminum chloride and magnesium sulphate, show a humidity adsorbing ability as remarkable as silica A gel sold on the market and are efficient enough to be used in dehumidifiers. Other magnesium salts and calcium salts are not efficient enough to be used in dehumidifiers. Among aluminum salts, aluminum chloride shows low humidity adsorbing ability compared with the other aluminum salts. It is possibly because aluminum chloride was hydrolyzed and therefore the aluminum silicate-gel producing reaction was not enough.
Sodium sulphate is produced as a by-product when the matrix is soaked in a water glass solution and treated with aluminum sulphate. When aluminum sulphate is added one after another to the same mother liquid, the proportion of sodium sulphate in the liquid increases. In order to see its effect, a similar test was conducted using a solution containing 19% of aluminum sulphate and 8.5% of sodium sulphate. As a result, shown as Al 2 (SO 4 ) 3 +Na 2 SO 4 in FIG. 3, exactly the same result was obtained as when only aluminum sulphate was used, and it was made clear that, even if the quantity of sodium sulphate increases in the mother liquid, it does not at all affect the quality of the element obtained.
FIG. 4 shows the equilibrium amount of adsorbed vapor at 25° C. per square meter of the ceramic fiber paper mentioned above in the example, on which adsorbent gel is fixed by being similarly impregnated with water glass, and then with aluminum sulphate solution of 60°-70° C. and of normal temperature, and with 19-21% solutions of aluminum chloride, of primary aluminum phosphate, of aluminum nitrate, of magnesium sulphate, of magnesium chloride, of calcium nitrate, and of calcium chloride of 60°-70° C., and with a solution containing 19% of aluminum sulphate and 8.5% of sodium sulphate of 60°-70° C.
FIG. 5 shows the equilibrium amounts (weight %) of adsorbed vapor at 25° C. in dehumidifier elements manufactured according to the above examples by the reaction of water glass with aluminum sulphate solutions of 60°-70° C. and of normal temperature, solutions of 60°-70° C. of primary aluminum phosphate, aluminum nitrate, aluminum chloride, magnesium sulphate, magnesium chloride, calcium chloride, calcium nitrate, and aluminum sulphate-sodium sulphate mixture, all of the same concentrations as mentioned above.
When the method of manufacturing a dehumidifier element of the present invention is used for mass production, metal salts such as aluminum sulphate should be added to the same mother liquid successively and by-products such as sodium sulphate should be removed from the mother liquid by cooling successively. In the case of using sodium silicate as water glass, the reaction to form metal silicate hydrogel are shown in Table 4 below:
TABLE 4______________________________________Na.sub.2 SiO.sub.3 + Al.sub.2 (SO.sub.4).sub.3 → Al.sub.2 (SiO.sub.3).sub.3 + Na.sub.2 SO.sub.4Na.sub.2 SiO.sub.3 + Al(H.sub.2 PO.sub.4).sub.3 → Al.sub.2 (SiO.sub.3).sub.3 + Na.sub.3 PO.sub.4Na.sub.2 SiO.sub.3 + AlCl.sub.3 → Al.sub.2 (SiO.sub.3).sub.3 + NaClNa.sub.2 SiO.sub.3 + Al(NO.sub.3).sub.3 → Al.sub.2 (SiO.sub.3).sub.3 + NaNO.sub.3Na.sub.2 SiO.sub.3 + MgSO.sub.4 → MgSiO.sub.3 + Na.sub.2 SO.sub.4Na.sub.2 SiO.sub.3 + MgCl.sub.2 → MgSiO.sub.3 + NaClNa.sub.2 SiO.sub.3 + Mg(NO.sub.3).sub.2 → MgSiO.sub.3 + NaNO.sub.3______________________________________
Magnesium phosphate is water insoluble and cannot be used, of the above-mentioned seven salts, aluminum phosphate is rather high-priced, rendering its use is impractical, and water soluble salts of aluminum and magnesium only are available at a reasonable price of the remaining six salts. Water solubility (weight %) of the six salts and water solubility of the three by-products of the reaction of the six salts and sodium silicate at 60° C. (temperature at the reaction) and at 0° C. (cooling temperature for precipitation and removal of by-products) are indicated in Table 5.
TABLE 5______________________________________ 60° C. 0° C.______________________________________Al.sub.2 (SO.sub.4).sub.3 31.0 27.5MgSO.sub.4 35.3 18.0Na.sub.2 SO.sub.4 31.1 4.3AlCl.sub.3 32.3 30.5MgCl.sub.2 37.9 34.6NaCl 27.1 26.3Al(NO.sub.3).sub.3 51.5 37.5Mg(NO.sub.3).sub.2 47.7 38.4NaNO.sub.3 55.4 42.2______________________________________
Solubilities of NaCl and of NaNO 3 in water are high at low temperatures and change only a little with temperature changes, and also have only a small difference with those of AlCl 3 , MgCl 2 and of Al(NO 3 ) 3 , Mg(NO 3 ) 2 respectively; therefore, NaCl and NaNO 3 cannot be precipitated and removed with the cooling of mother liquids after the reaction.
Solubility of Na 2 SO 4 is high in warm water and low in cold water, and solubilities of Al 2 (SO 4 ) 3 and of MgSO 4 are high in cold water as well as in warm water; therefore, Na 2 SO 4 only can be precipitated and removed from the mother liquids containing Na 2 SO 4 and Al 2 (SO 4 ) 3 or containing Na 2 SO 4 and MgSO 4 by cooling the mother liquids after reacting sodium silicate and the metal sulphate.
There is potassium silicate in the compounds called as water glass in the wide sense. This potassium silicate has also been checked for whether it can be used as "water glass" in the present invention.
The water-solubilities of the by-products produced by the reaction of potassium silicate and the above-mentioned six metal salts at 60° C. and 0° C. are given below in Table 6:
TABLE 6______________________________________ 60° C. 0° C.______________________________________K.sub.2 SO.sub.4 15.4 7.2KCl 31.4 21.9KNO.sub.3 52.2 11.7______________________________________
It is supposed that K 2 SO 4 only can be probably precipitated and removed from the mother liquid, but potassium silicate is pretty high-priced and not preferable.
FIG. 6 shows how a dehumidifier is built with the cylindrical dehumidifier element 11 shown in FIG. 2. The dehumidifier element 11 is held rotably in a casing 12 which is divided into a processing zone 14 and a regenerating zone 15 by a separator 13, and is rotated by a geared motor 16 and a driving belt 17. Highly humid feed air 18 is sent into the processing zone 14, and water vapor is adsorbed by the element 11 therefrom. Hot and less humid desorbing air 19 is sent into the regenerating zone 15 to regenerate and dehumidify the element 11. Dry air 20 is thus continuously obtained. In FIG. 6, 21 is a pulley, 22 is a tension pulley, 23 is a rubber seal and 24 is a heater for the desorbing air.
For comparison purposes, dehumidifiers of the structure shown in FIG. 6 were built using two different dehumidifier elements. One was obtained, according to the examples presented above, by forming ceramic fiber paper as shown in FIG. 1 into the single-faced corrugated sheet 9 having a wave length of 3 mm and a wave height of 2 mm, firing or treating with air having a temperature of 200°-500° C., rolling the corrugated sheet up to a diameter of 320 mm and a thickness of 200 mm, and then soaking the rolled matrix in a water glass solution and in an aluminum sulphate solution. The second dehumidifier is an absorbing element, an was obtained by forming the same ceramic fiber paper in the same size in accordance with the present invention, and then impregnating it with 8% (weight % of the formed block) of lithium chloride as an absorbent. FIG. 7 shows the relation of absolute humidities (g/kg) of feed air 18 at the inlet and at the outlet with 2 m/sec wind velocity of the air 18 and of the desorbing air 19 in front of the element, with a ratio of 1 to 3 of the flow amounts of the desorbing air and the feed air during a given period of time, with an 18 r.p.h. rotating speed of the element, with a feed air temperature of 20° C. at the inlet and with a desorbing air temperature of 140° C. at the inlet, the absolute humidity of desorbing air at the inlet being the same as the absolute humidity of the feed air at the inlet.
As is made clear from the above, sufficient adsorbing ability for a dehumidifier element is obtained, and large numbers of dehumidifier element can be manufactured successively, when aluminum sulphate or magnesium sulphate is used. When aluminum chloride, magnesium chloride or calcium salts are used elements obtained are not efficient enough to be used as dehumidifiers, though they can be used as total heat energy exchangers.
It is also apparent that water glass, which has a high chemical affinity with inorganic fiber, not only moistens the surface of the inorganic fiber paper but also permeates into the apertures between the fibers of the inorganic fiber paper, and then reacts with water-soluble aluminum sulphate or magnesium sulphate to produce a gel of silicates. The silicate hydrogels are therefore tightly bound even to the inside of the low density inorganic fiber paper. When water glass reacts with metal sulphates after the impregnated water glass is concentrated and dried to form hydrated water glass or half-solid state water glass of 5-45% of water content, the content of SiO 2 in the water glass before it changes into gel is 50-70% and the water content of silicate hydrogel obtained becomes 40-50%; therefore, the gel is strong, the binding strength of the gel to the inorganic fiber paper is sufficient and there is no possibility of the hydrogel bound to the inorganic fiber paper falling off because of washing with water after the reaction. Moreover, the hydrogel produced in this way is dried to form an aerogel having 40-50% volume of minute pores, and it scarcely shrinks during drying; therefore, the aerogel has no cracks and it cannot break into small pieces. Thus, a strong aerogel tightly bound to the paper is obtained.
It is also apparent that, as the organic substances in the honeycomb matrix are removed by the firing process, the dehumidifier element of the present invention can be safely used for the continuous dehumidification of air or other inert gases, in which the element is regenerated by introducing a hot regeneration air to desorb the adsorbed humidity, while precluding the possibility of combustion of the element with the high temperature regeneration air.
In prior dehumidifier elements, organic or inorganic adhesives having no humidity adsorbing abilities were used in the forming process. The part of the element coated with adhesive did not at all contribute to the humidity adsorbing performance, and the effective surface area of the element was lessened by 10-20%. But in the present invention, water glass can be used as an adhesive in the laminating process to form the matrix, which converts into silicate aerogel together with the water glass impregnated all over the element by the reaction with metal sulphates, without decreasing adhering solidity of inorganic fiber paper in the element. Thus, the humidity adsorbing performance of the element is 10-20% better than the prior one.
The dehumidifier element obtained by the present invention shows, from the above data, excellent humidity adsorbing performance. At the same time, it has many characteristics such that it can be manufactured in mass production with inexpensive materials easily and reliably.
The dehumidifier element in the present invention can be formed not only into the rotary type element shown in FIG. 2, but also into the cross-flow type element shown in FIG. 8 and into the counter-flow type element shown in FIG. 9. | A dehumidifier element is produced by alternately laminating corrugated paper and flat liner paper, both papers being of low density and composed of inorganic fiber such as ceramic fiber, to form a honeycomb matrix having many small channels penetrating through opposite surfaces. The formed matrix is fired with hot air to remove organic substances contained in the sheets, or the sheets may be fired before the lamination. The matrix is impregnated with water glass after the laminating process, or the sheets are impregnated before the laminating process. In either case, the formed matrix is soaked in an aqueous solution of aluminum sulphate or magnesium sulphate to form a silicate hydrogel on the papers and in the apertures between fibers of the papers. The shaped matrix and the metal silicate hydrogel are washed and dried to obtain a dehumidifying element having physical strength. The metal sulphate solution is cooled to precipitate and remove sodium sulphate from the solution. Additional sulphate is added to the metal sulphate solution for repeating the manufacturing process for another dehumidifier element. The main constituent of the element is metal silicate aerogel deposited in the apertures between the fibers of the inorganic fiber paper and on the inorganic fiber paper, which acts as an adsorbent. | 8 |
FIELD OF THE INVENTION
[0001] The present invention relates to aqueous concentrated surfactant compositions suitable to be diluted by consumer prior to use.
[0002] The present invention provides a composition comprising a surfactant basis comprising one or more anionic surfactants, one or more non-ionic surfactants, and one electrolyte, preferably in combination with one or more amphoteric surfactants and/or a solvent, and having a total active matter higher than 45 wt % based on the sum of the surfactants above that, upon dilution with water, exhibit a viscosity higher than the concentrate, adapted for preparing liquid cleaning compositions ready to be used, particularly useful for dishwashing.
STATE OF THE ART
[0003] The industry is interested in finding solutions to produce more ecologic and more profitable cleaning products while satisfying the final consumer expectations and needs. One of the trends in this regard, specially relevant for home care, and in particular for dishwashing products, is the production of highly concentrated products to be diluted by the final consumer to those concentrations suitable for the final use. The commercialization of highly concentrated products instead of ready to use formulations has several advantages. For instance, the costs associated with packaging and transportation are considerably lowered, since water contents of the product is minimized the volume of the commercialized product is then significantly reduced. Also, water contents reduction makes possible lessening, or even eliminate, the necessity for preservatives, since the low water contents of concentrated products makes usually them an inadequate media for microorganism growth.
[0004] The suitable dilutable concentrated products are those products characterized by a set of features which enable the final consumer their practical use. Among said features, the unwavering one is having the appropriate viscosity/concentration profile, i.e. increased viscosity of the diluted forms compared with the concentrated product. The concentrated product shall be homogeneous and low viscous and able to easily incorporate the water when added in order to prepare the diluted product, indeed, ideally, the dilution should be easily prepared by manual shaking. The resulting diluted product shall be also homogeneous while showing high enough viscosity values. A high enough viscosity value is necessary in order the final consumer can handle the product and control the amount of product spread onto the material to be cleaned, which allows control of dosage. However, viscosity shall not rise in excess since too viscous products do not flow easily which makes difficult their use and dosing them.
[0005] The use of electrolytes is one of the very well known approaches in the art to obtain dilutable and concentrated surfactant compositions that thicken upon dilution. For instance, WO94/16680 discloses that the ratio of electrolytes to surfactants in aqueous dilution-thickening personal washing composition is sufficient to form a lamellar phase, which enables to obtain a highly concentrated composition having a viscosity which is low enough for processing, packaging and dispensing. Upon the addition of water, these compositions are described to thicken in use.
[0006] One of the drawbacks of using electrolytes to obtain highly concentrated dilution-thickening compositions regards to the high amount of electrolyte in the media, which might cause problems from the stability perspective and/or might be inadequate for some applications of the surfactant composition.
[0007] In U.S. Pat. No. 5,922,664 aqueous detergent concentrates containing a mixture of two or more surfactants that differ in their respective resistance to electrolytic salting out are described. It is disclosed that, upon dilution, the surfactant system organization is transformed from micellar phase to lamellar phase, and this produces an increase in viscosity such that the diluted concentrate has a viscosity equal to or higher than the viscosity of the original concentrate. However, the viscosity increase is dependent on the surfactant combination that apparently not allows for highly concentrated dilutable compositions.
[0008] Thus, the use of regulators and coregulators of the viscosity has been proposed in order to obtain a highly concentrated dilutable composition of satisfactory viscosity.
[0009] U.S. Pat. No. 5,057,246 discloses highly concentrated liquid detergent compositions containing at least one anionic surface agent and a regulator of the viscosity of the diluted composition, consisting of at least one surface active agent chosen from the group formed by nonionic, amphoteric and zwitterionic surface agents, in combination with at least one coregulator of viscosity consisting of an acid or its salt in such quantity that it is dissolved in the concentrated composition. The concentrated detergent compositions are capable of being poured, while the surfactant agent and the acid/salt are being chosen so that the viscosity of the diluted composition is controllable and may increase upon dilution relative to the viscosity of the concentrated composition.
[0010] Despite the attempts in the art to obtain concentrated dilutable cleaning compositions, still there is the need for compositions which meet all the ideal requirements, namely:
surfactant composition has a high active the concentrated matter content; and is easy to formulate; and the compositions are easy to dilute by using simply manual shaking; and the diluted composition exhibit a viscosity that is satisfactory to the consumer; and the diluted composition exhibit good performance (e.g. foaming properties and cleaning ability).
Additional possible advantages are:
[0016] the use of materials from natural origin means an additional advantage from the perspective of the green profile of the formulations.
[0017] mildness of the components of the surfactant composition increasing skin tolerance is an advantage when the use of the cleaning composition, as is the case in dishwashing, involves the contact with the human skin.
[0018] the possibility of the concentrated compositions to be formulated at both acid and slightly basic pH values
SUMMARY OF THE INVENTION
[0019] According to a first aspect the present invention provides a concentrated dilutable cleaning composition comprising:
[0020] (a) one or more anionic surfactants
[0021] (c) one or more non-ionic surfactants comprising one or more polyethoxylated glycerin ester compounds
[0022] (d) an electrolyte
[0023] and optionally
[0024] (b) one or more amphoteric surfactants
[0025] (e) one or more solvents
[0026] (f) one or more pH adjuster agents
[0027] and
[0028] (g) water up to 100 wt % of the composition;
[0029] wherein the total active matter of the composition calculated from the sum of (a), (c), and (b) if present, is from 45 wt % to less than 100 wt %, preferably from 45 wt % to 80 wt %, more preferably from 45 to 60 wt %, even more preferably 47 wt % to 80 wt %, most preferred from 47 wt % to 60 wt %, even most preferred from 50 wt % to 60 wt %, taking as a whole the concentrated composition.
[0030] According to a second aspect the present invention provides a diluted cleaning composition prepared upon dilution with water of the concentrated composition.
[0031] According to a third aspect the present invention provides a medium diluted cleaning composition with a total active matter from more than 20 to 35 wt % prepared from dilution with water of a concentrated composition according to the invention.
[0032] According to a fourth aspect the present invention provides a highly diluted cleaning composition with a total active matter from more than 5 to less than 20 wt % prepared from dilution with water of a concentrated composition according to the invention.
[0033] According to a fifth aspect the present invention provides a method to prepare a concentrated dilutable composition according to the invention.
[0034] According to a sixth aspect the present invention provides a method to prepare a diluted composition, a medium diluted composition or a highly diluted composition according to the invention.
[0035] According to a further aspect, the present invention provides a method of cleaning comprising contacting said surface with a concentrated, a diluted, a medium diluted or a highly diluted cleaning composition as hereinbefore defined.
[0036] According to a further aspect, the present invention provides a method of cleaning comprising using a composition according to the invention.
[0037] According to an additional aspect the present invention provides a method of manual dishwashing using a composition according to the invention.
[0038] The inventors of the present invention have found that the concentrated dilutable cleansing compositions based on the particular ingredients at the particular ratios according to the invention are able to meet all the desirable requirements for concentrated dilutable compositions. The concentrated dilutable composition according to the invention has an active matter content higher than 45 wt %, preferably higher than 47 wt %, most preferred higher than 50 wt %, being easy to formulate, exhibiting homogeneity, stability and a viscosity that is satisfactory to the consumer while being easy to dilute by using simply manual shaking, providing fast enough a diluted, a medium diluted or a highly diluted cleaning composition characterized in:
High stability A suitable viscosity Good performance properties (foam properties, dirt cleaning ability) when used for manual dishwashing.
[0042] Besides, the concentrated compositions according to the invention comprise materials from natural origin. The components satisfy the consumer needs from the perspective of mildness and skin tolerance when contact with the human skin.
DETAILED DESCRIPTION OF THE INVENTION
[0043] The present invention provides a concentrated dilutable cleaning composition, comprising:
[0044] (a) one or more anionic surfactants
[0045] (c) one or more non-ionic surfactants comprising one or more polyethoxylated glycerin ester compounds
[0046] (d) an electrolyte
[0047] and optionally
[0048] (b) one or more amphoteric surfactants
[0049] (e) one or more solvents
[0050] (f) one or more pH adjuster agents
[0051] and
[0052] (g) water up to 100 wt % of the composition;
[0053] wherein the total active matter of the composition calculated from the sum of (a), (c), and (b) if present, is from 45 wt % to less than 100 wt %, preferably from 45 wt % to 80 wt %, more preferably from 45 to 60 wt %, even more preferably 47 wt % to 80 wt %, most preferred from 47 wt % to 60 wt %, taking as a whole the concentrated composition.
The Active Matter
[0054] The active matter corresponds to the active matter weight-percent (wt %) calculated from the sum (a)+(c) of the active matter of all anionic surfactants (a) and all non-ionic surfactants (c) in the composition; and if one or more amphoteric surfactants (b) are present, the active matter corresponds to the active matter weight-percent calculated from the sum (a)+(b)+(c) of the active matter of all anionic surfactants (a), all non-ionic surfactants (c) and all amphoteric surfactants (b) in the composition.
The Component (a)
[0055] The composition according to the invention comprises a component (a) comprising one or more anionic surfactants. Examples of suitable anionic surfactants according to the invention include, but are not limited to, alkyl ether sulfates, alkyl sulfates, alkyl sulfonate, alkene sulfonate such as sodium alpha-olefin sulfonate, alkyl aryl sulfonates, sulfosuccinates, sulfosuccinamates, N-alkoyl sarcosinates, alkyl phosphates, alkyl ether phosphates, alkyl amino acids, alkyl peptides, alkyoyl taurates, carboxylic acids, acyl and alkyl glutamates, alkyl isethionates, alkyl ether carboxylates, etc introduced in the composition in the acid form or in the form of a salt, for instance in the form of sodium potassium, calcium, magnesium, ammonium, mono-, di-, or tri-ethanolamine salt, etc.
[0056] In a preferred embodiment the component (a) comprises one or more compounds of Formula (I):
[0000] R 1 —O—(CH 2 —CH(R 2 )—O) n (CH 2 CH 2 O) m —SO 3 − (A) 1/z z+ (I)
[0057] wherein R 1 is a linear or branched, saturated or unsaturated alkyl alkenyl chain having from 4 to 30 carbon atoms, R 2 is a C1-C3 linear or branched alkyl chain, A is a suitable countercation, n and m are 0 or an integer number between 1 to 30, and wherein the sum of m+n is from 0 to 30, preferably from 1 to 15 z is 1, 2 or 3.
[0058] The component (a) preferably consists of one, two or more compounds of Formula (I).
[0059] Preferred compounds of Formula I are alkyl(ether)sulphates that can be used alone or in combination with other anionic surfactants.
[0060] In formula I, A z+ is a suitable countercation. Alkyl(ether)sulfate metal salts of alkyl(ether)sulfates as well as ammonium salts or organic amine salts with alkyl or hydroxyalkyl substituent can be used as component I in the compositions according to the invention.
[0061] In formula I, n and m are 0 or an integer number between 1 to 30, and the sum of m+n is from 0 to 30, preferably from 1 to 15. More preferably, m is not higher than 2 and the sum m+n is below 15. Even more preferred m is 0 and n is below 12. Most preferred the compound (a) comprises a mixture of sodium alkyl ether sulfates with m being zero and with n having an average comprised between 0.5 and 7, more preferably n is comprised between 1 and 5.
[0062] The preferred compounds of Formula I according to the invention are metal salts of alkyl ether sulfates as well as ammonium salts or organic amine salts with alkyl or hydroxyalkyl substituent R 1 , wherein R 1 is an alkyl chain having between 2 and 14 carbon atoms, with m being zero and n being a value comprised between 1 and 5.
[0063] Sodium lauryl ether sulfate (INCI name Sodium Laureth Sulfate) preferably with an average degree of ethoxylation comprised between 1 and 3, is particularly preferred as an anionic surfactant, more preferably between 1 and 2.5, even more preferably between 2 and 2.5.
[0064] Examples of commercially available alkyl ether sulfate type anionic surfactants are those with the commercial reference EMAL® 270D, EMAL® 270E (INCI name Sodium Laureth Sulfate) and EMAL® 227 marketed by KAO Chemicals Europe.
[0065] The anionic surfactant (a) can be a mixture of two or more anionic surfactants, or a single anionic surfactant such as an alkyl ether sulfate type surfactant. The preferred weight percentage of the anionic surfactant (a) with respect to the total active matter of the composition is 0.1 to 90 wt %, preferably from 20 to 90 wt %, more preferably from 40 to 85 wt % most preferred from 50 to 85 wt %.
The Component (b)
[0066] The composition according to the invention optionally but preferably comprises a component (b) which comprises one or more amphoteric surfactants. Amphoteric surfactants include ampholytes and betaines.
[0067] In a preferred embodiment the component (b) of the composition according to the invention comprises one or more betaines. Specific examples of betaines are alkyl betaines, alkyl sulphobetaines (sultaines), amidoalkyl betaines, alkyl glycinates, alkyl carboxyglycinates, alkyl amphoacetates, alkyl amphopropionates, alkylamphoglycinates, alkyl amidopropyl betaines and hydroxysultaines. Particularly preferred betaines are alkyl amidopropyl betaines, alkyl amidopropyl hydroxysultaines, alkyl hydroxysultaines and alkyl amphoacetates. Examples of commercially available useful amphoteric surfactants according to the invention are BETADET® HR, BETADET® HR-50K, BETADET® S-20, BETADET® SHR and BETADET® THC-2, all marketed by Kao Chemicals Europe.
[0068] In a preferred embodiment of the invention the component b) of the composition according to the invention comprises one or more ampholytes. Specific examples of ampholytes are amine oxides. Suitable amine oxides according to the present invention are amine oxides with a hydrocarbon chain containing between 8 and 18 carbon atoms.
[0069] The amine oxides of Formula (II) are especially preferred
[0000]
[0070] wherein
[0000] R 1 represents a linear or branched, saturated or unsaturated alkyl or alkenyl group containing between 8 and 18 carbon atoms;
[0071] R 2 represents an alkylene group containing between 1 and 6 carbon atoms;
[0072] A represents a group selected from —COO—, CONH—, —OC(O)— and —NHCO—;
[0073] x represents 0 or 1;
[0074] and R 3 and R 4 independently of one another represent an alkyl or hydroxyalkyl group containing between 1 and 3 carbon atoms.
[0075] The component (b) preferably consists of one, two or more compounds of Formula (II).
[0076] According to the invention, in the amine oxides of general Formula (II), R 1 is preferably a linear or branched, saturated or unsaturated, alkyl or alkenyl group containing between 10 and 16 carbon atoms, preferably an alkyl or alkenyl group containing between 10 and 14 carbon atoms, more preferably a lauric group (12 carbon atoms) and/or a myristic group (14 carbon atoms).
[0077] In a preferred embodiment, in the amine oxides of general formula (II): x is 1, A is a —COO— or —CONH— group, more preferably —CONH—; R 2 is also preferably a methylene (—CH2-), ethylene (—CH2-CH2-) group or propylene group (—CH2-CH2-CH2-). R 3 and R 4 are also preferably each a methyl group.
[0078] In another preferred embodiment of the invention, in the amine oxides of general formula (II): x is 0, R 3 and R 4 each a methyl group and R 1 is a lauric group (12 carbon atoms) and/or a myristic group (14 carbon atoms).
[0079] In a specially preferred embodiment of the invention the component (b) of the composition according to the invention comprises at least two compounds of Formula (II) being the proportion having R 1 C 12 or C 14 higher than 60 wt %.
[0080] In a very specially preferred embodiment of the invention the component (b) of the composition according to the invention comprises at least two compounds of Formula (II) being the proportion having R 1 C 12 or C 14 being higher than 60 wt % wherein x is 0.
[0081] In another very specially preferred embodiment of the invention the component (b) of the composition according to the invention consists in at least two compounds of Formula (II) being the proportion having R 1 C 12 or C 14 being higher than 60 wt % wherein x is 0.
[0082] Examples of commercially available amine oxides of Formula (II) are those with the commercial reference OXIDET® DM-20 (INCI name Lauramine Oxide), OXIDET® DMCLD (INCI name Cocamine Oxide)OXIDET® DM-246 (INCI name Cocamine Oxide), OXIDET® DM-4 (INCI name Myristamine Oxide), OXIDET® L-75 (INCI name Cocamidopropylamine Oxide), all of them marketed by KAO Chemicals Europe.
[0083] The amphoteric surfactant (b) can be a mixture of two or more amphoteric surfactants, or a single amphoteric surfactant. The preferred weight percentage of the amphoteric surfactant (b) with respect to the total active matter of the composition is 0.1 to 65 wt %, preferably from 1 to 65 wt %, more preferably 5 to 40 wt %, most preferred 10 to 30 wt %.
The Component (c)
[0084] The composition according to the invention comprises component (c) which comprises one or more polyethoxylated glycerine ester compounds. Preferably, the polyethoxylated glycerine ester composition comprises a mixture of compounds of Formula (IV):
[0000]
[0000] wherein each one of m, n, or 1 represents, independently, a number of 0 to 200, the sum of m, n and 1 being in the range of 1 to 200, B being a hydrogen atom or an acyl group represented by —CO—R′, R′ representing a hydrogen, alkyl or alkenyl group, linear or branched, with 3 to 21 carbon atoms, preferably with 5 to 17 carbon atoms, more preferably with 5 to 11 carbon atoms, wherein the mixture comprises the following compounds i. to iv.:
[0085] i. at least one component represented by Formula (IV), wherein, independently, one of the groups B represents an acyl group represented by —CO—R′ and the remaining ones represent H
[0086] ii. at least one component represented by Formula (IV), wherein, independently, two of the groups B represent an acyl group represented by —CO—R′ and the remaining one represents H;
[0087] iii. at least one component represented by Formula (IV), wherein, independently, each one of the groups B represents an acyl group represented by —CO—R′;
[0088] iv. at least one component represented by Formula (IV), wherein each one of groups B represents H.
[0089] Such mixtures of alkoxylated glycerides and alkoxylated glycerine can be prepared by using the preparation methods as described in the European patent applications EP-A-0579887, EP-A-0586323, EP-A-1045021, and EP-A-2029711B1 and are commercially available under the trademark LEVENOL® and EMANON marketed by Kao Chemicals Europe.
[0090] In a preferred embodiment the proportion by weight of the species (i)/(ii)/(iii) is in the range 46-90/9-35/1-15.
[0091] In a further preferred embodiment the proportion by weight (i)+(ii)+(iii)/(iv) is in the range of 3.0:0.3 to 0.5:3.0.
[0092] In an even more preferred embodiment each one of m, n, or 1 represents, independently, a number from 0 to 9, the sum of m, n and 1 being in the range of over 5 and less than 9, characterized in that in the acyl group represented by —CO—R, R represents an alkyl or alkenyl group, linear or branched, of 6 to 9 carbon atoms, and preferably the proportion by weight (i)+(ii)+(iii)/(iv) is in the range of 2.0:0.5 to 0.5:3, more preferably the proportion by weight (i)+(ii)+(iii)/(iv) is in the range of 1.5:0.8 to 0.8:2.5, and preferably the proportion by weight of components (i)/(ii)/(iii) is 60-90/10-35/less than 10.
[0093] In addition to the ethoxylated glycerin partial ester the composition according to the invention may comprise other non-ionic cosurfactants. The general definition and general properties of non-ionic surfactants are well-known by the skilled in the art. The definition in “NONIONIC SURFACTANTS—Chemical Analysis” ISBN 0-8247-7626-7 is incorporated herein by reference.
[0094] Examples of non-ionic co-surfactants according to the invention include like alkanolamides, alkoxylated alkanolamides, alkoxylated trimethyolol propane, alkoxylated 1,2,3-trihydroxy hexane, alkoxylated pentaetrythritol, alkoxylated sorbitol, alkoxylated glycerol fatty acid partial ester, alkoxylated trimethyolol propane fatty acid ester, alkoxylated 1,2,3-trihydroxy hexane fatty acid ester, alkoxylated pentaetrythritol fatty acid ester, alkoxylated sorbitol fatty acid ester, fatty alcohol, fatty alcohol polyglycol ethers, alkylphenol, alkylphenol polyglycol ethers, fatty acid polyglycol esters, fatty acid amide polyglycol ethers, fatty amine polyglycol ethers, mixed ethers and mixed formals, optionally partly oxidized alk(en)yl oligoglycosides or glucuronic acid derivatives, fatty acid-N-alkylglucamides, ethoxylated glucamine derivatives, protein hydrolyzates (particularly wheat-based vegetable products), polyol fatty acid esters, sugar esters, alkyl polyglucosides, sorbitan esters and polysorbates, Cocamide MEA, Cocamide DEA, PEG-4 Rapeseedamide, Trideceth-2 Carboxamide MEA, PEG-5 Cocamide, PEG-6 Cocamide and PEG-14 Cocamide. Examples of commercially available useful non-ionic surfactants according to the invention are AMIDET® N, AMIDET® A15, AMIDET® A/17, AMIDET® A/26, AMIDET® A-111-P, AMIDET® B-112, LEVENOL® H&B, LEVENOL® C-241, LEVENOL® C-301 and LEVENOL® C-201, LEVENOL F200, EMANON XLF, MYDOL®-10, KALCOL, KAOPAN, RHEODOL and FINDET 10/15 (Polyoxyethylene(3) alkyl(C8-12) ethers), FINDET 10/18 (Polyoxyethylene(6) alkyl(C8-12) ethers), FINDET 1214N/14 (Polyoxyethylene(2) alkyl(C12-14) ethers), FINDET 1214N/15 (Polyoxyethylene(3) alkyl(C12-14) ethers), FINDET 1214N/16 (Polyoxyethylene(2) alkyl(C12-14) ethers), FINDET 1214N/19 (Polyoxyethylene(7) alkyl(C12-14) ethers), FINDET 1214N/21 (Polyoxyethylene(9) alkyl(C12-14) ethers), FINDET 1214N/23 (Polyoxyethylene(11) alkyl(C12-14) ethers), FINDET 13/17 (Polyoxyethylene (5) isotridecyl alcohol), FINDET 13/18.5 (Polyoxyethylene (6.5) isotridecyl alcohol), FINDET 13/21 (Polyoxyethylene (9) isotridecyl alcohol), FINDET 16/36 (Polyoxyethylene(24) alkyl(C16) ethers), FINDET 1618A/18 (Polyoxyethylene(6) alkyl(C16-18) ethers), FINDET 1618A/20 (Polyoxyethylene(8) alkyl(C16-18) ethers), FINDET 1618A/23 (Polyoxyethylene(11) alkyl(C16-18) ethers), FINDET 1618A/35-P (Polyoxyethylene(23) alkyl(C16-18) ethers), FINDET 1618A/52 (Polyoxyethylene(40) alkyl(C16-18) ethers), FINDET 1618A/72-P (Polyoxyethylene(60) alkyl(C16-18) ethers), FINDET 18/27 (Polyoxyethylene(15) alkyl(C18) ethers), FINDET 1816/14 (Polyoxyethylene(1.9) alkyl(C16-18 and C18-unsaturated) ethers), FINDET 1816/18 (Polyoxyethylene(6) alkyl(C16-18 and C18-unsaturated) ethers), FINDET 1816/3220 (Polyoxyethylene(20) alkyl(C16-18 and C18-unsaturated) ethers), FINDET 1816/32-E (Polyoxyethylene(20) alkyl(C16-18 and C18-unsaturated) ethers), FINDET AR/30 (Polyoxyethylene (18) castor oil.), FINDET AR-45 (Polyoxyethylene (33) castor oil), FINDET AR-52 (Polyoxyethylene (40) Hydrogenated castor oil), FINDET ARH-52 (Polyoxyethylene (40) castor oil), FINDET K-060 (Polyoxyethylene Coconut monoethanolamide), FINDET LI/1990 (Polyoxyethylene (7) fatty branched alcohol), FINDET LN/8750 (Polyoxyethylene (75) lanolin), FINDET LR4/2585 (Polyoxyethylene (13) fatty branched alcohol), FINDET OR/16 (Polyoxyethylene (4 EO) unsaturated fatty acid), FINDET OR/22 (Polyoxyethylene (10) unsaturated fatty acid), FINDET OR/25 (Polyoxyethylene (13) unsaturated fatty acid), FINDET ORD/17.4 (Polyoxyethylene (5,4) unsaturated fatty acid.), FINDET ORD/32 (Polyoxyethylene (20) unsaturated fatty acid), FINDET PG68/52-P (Polyoxyethylene(40) alkyl(C16-18) ethers), FINDET SE-2411 (Polyoxyethylene and polyoxypropylene decyl alcohol), (cetyl alcohol), (Octyl alcohol), KALCOL 1098 (Decyl alcohol), KALCOL 200GD (Octyl dodecanol), KALCOL 0880KALCOL 2098 (Lauryl alcohol), KALCOL 220-80 (Behenyl alcohol), KALCOL 2450 (Alcohol C 10-18 ), KALCOL 2455 (Alcohol C 10-18 ), KALCOL 2463 (Alcohol C 10-18 ), KALCOL 2470 (Alcohol C 12-16 ), KALCOL 2473 (Alcohol C 12-16 ), KALCOL 2474 (Alcohol C 12-14 ), KALCOL 2475 (Alcohol C 12-14 ), KALCOL 4098 (Myristyl alcohol), KALCOL 4250 (Alcohol C 12-16 ), KALCOL 6098 (Cetyl Alcohol), KALCOL 6850 (Alcohol C 14-18 ), KALCOL 6850 P (Alcohol C 14-18 ), KALCOL 6870 (Alcohol C 14-18 ), KALCOL 6870 P (Alcohol C 14-18 ), KALCOL 8098 (Stearyl alcohol), KALCOL 8665 (Alcohol C 16-18 ), KALCOL 8688, FARMIN CS (Coconut amine), FARMIN 08D (Octyl amine), FARMIN 20D (Lauryl amine), FARMIN 80 (Stearyl amine), FARMIN 86T (Stearyl amine), FARMIN O (Oleyl amine), FARMIN T (Tallow amine), FARMIN D86 (Distearyl amine), FARMIN DM24C (Dimethyl coconut amine), FARMIN DM0898 (Dimethyl octyl amine), FARMIN DM1098 (Dimethyl decyl amine), FARMIN DM2098 (Dimethyl lauryl amine), FARMIN DM2463 (Dimethyl lauryl amine), FARMIN DM2458 (Dimethyl lauryl amine), FARMIN DM4098 (Dimethyl myristyl amine), FARMIN DM4662 (Dimethyl myristyl amine), FARMIN DM6098 (Dimethyl palmityl amine), FARMIN DM6875 (Dimethyl palmityl amine), FARMIN DM8680 (Dimethyl stearyl amine), FARMIN DM8098 (Dimethyl stearyl amine), FARMIN DM2285 (Dimethyl behenyl amine), FARMIN M2-2095 (Didodecyl monomethyl amine), DIAMIN R-86 (Hydrogenated tallow propylene diamine), DIAMIN RRT (Tallow propylene diamine), FATTY AMIDE S (Stearamide), FATTY AMIDE T (Stearamide), AMIET 102 (Polyoxyethylene alkyl amine), AMIET 105 (Polyoxyethylene alkyl amine), AMIET 105A (Polyoxyethylene alkyl amine), AMIET 302 (Polyoxyethylene alkyl amine), AMIET 320 (Polyoxyethylene alkyl amine), AMIET TD/23 (Polyoxyethylene(11) Tallow amine), AMIET OD/14 (Polyoxyethylene(2) oleyl amine), AMINON PK-02S (Alkyl alkanolamide), AMINON L-02 (Alkyl alkanolamide), AMIDET A-15 (Fatty acid monoethanolamide), AMIDET A111 (Coconut oil fatty acid ethanolamide), AMIDET B-112 (Coconut oil fatty acid diethanolamide), AMIDET B-120 (Linolenic acid diethanolamide), AMIDET KDE (Coconut oil fatty acid diethanolamide), AMIDET SB-13 (Coconut oil fatty acid diethanolamide), FINDET K-060 (Polyoxyethylene Coconut monoethanolamide, marketed by Kao Chemicals Europe and Kao Corporation.
[0095] The non-ionic surfactant (c) can be a mixture of two or more non-ionic surfactants, or a single non-ionic surfactant. The preferred weight percentage of the non-ionic surfactant (c) with respect to the total active matter of the composition is from 0.1 to 90 wt %, preferably from 1 to 80 wt %, more preferably from 5 to 30 wt %, most preferred from 5 to 20 wt %.
The Component (d)
[0096] It is well known in the art that electrolytes are able to interact with surfactants in aqueous solution modifying the aggregation form of said surfactants leading thus to viscosity curves with surfactant concentration different to that observed in the absence of the electrolyte. The effects of electrolytes in this regard are usually interpreted in terms of their interactions with the structure of the micelle solution, the interactions between surfactants cylindrical aggregates, the transition between different surfactants lamellar phases, electrostatic interactions between ions and micelles, ionic hydratability and changes in the water structure. In general, it is known that the presence of the electrolyte in the diluted composition causes the development of more viscous surfactant phases, frequently the viscosity enhancement being the consequence of the reorganization of micellar phases (relatively low viscous) to the development of more viscous lamellar phases, which consist in certain arrangement of cylindrical aggregates of the surfactants.
[0097] The composition according to the invention comprises a component (d) comprising one electrolyte. Electrolytes according to the invention comprise both inorganic and/or organic electrolytes.
[0098] Suitable organic electrolytes according to the invention include short chain organic acid metal salts like citrates, acetates, lactates, oxalates, and the like and mixtures thereof. Suitable inorganic electrolytes include metalsulphates, chlorides, fluorides, iodides, sulphates, phosphates, nitrates, carbonates, hydrogencarbonates like those of sodium, potassium, calcium, magnesium and the like, and mixtures thereof.
[0099] In a preferred embodiment the composition according to the invention comprises an electrolyte comprising sodium chloride and/or magnesium chloride, more preferably magnesium chloride.
[0100] The electrolyte (d) can be a mixture of two or more electrolytes, or a single electrolyte. The preferred weight percentage of the electrolyte (d) with respect to the total weight of the composition is 1.5 to 8 wt %, more preferably 2 to 6 wt %.
The Component (e)
[0101] The composition according to the invention optionally comprises a component (e) comprising one or more solvents. Solvents can contribute to both the stability of the formulation and as improvers of the cleaning ability of the compositions according to the invention.
[0102] Examples of suitable solvents according to the invention are hydrocarbons (aromatic or aliphatic), halogenated hydrocarbons like chlorinated hydrocarbons, ether compounds, ketone compounds, aldehyde compounds, and mixtures thereof.
[0103] In a preferred embodiment the component (e) comprises one or more alkanols. Examples of alkanols according to the invention are methanol, ethanol, isopropanol, propanol.
[0104] In another embodiment of the invention the component (e) comprises ethers and glycols. Examples of suitable ethers and glycols according to the invention include mono and di alkyl ethers of alkylene glycols, dialkylene glycols, trialkylene glycols, polyglycols, propylene glycol, polyethylene glycol, polypropylene glycol, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, and triethyleneglycol.
[0105] The solvent (e) can be a mixture of two or more solvents, or a single solvent. The preferred weight percentage of the solvent (e) with respect to the total weight of the composition is 5 to 15 wt %, more preferably 6 to 12 wt %.
The Component (f)
[0106] In a preferred embodiment the composition according to the invention comprises a component (f) comprising a pH adjuster. The amount of pH adjuster added to the composition of the invention will be determined by the composition of the invention and the target pH.
[0107] Examples of suitable pH adjusters according to the invention are inorganic acids like hydrogen chloride acid and the like or organic acids like lactic acid and the like, inorganic bases like sodium carbonate, and organic bases and mixtures thereof.
[0108] In one embodiment of the invention the pH adjuster comprises an organic acid. Organic acids include, but are not limited to, formic acid, acetic acid, propanoic acid, propionic acid, glycolic acid, sorbic acid, oxalic acid, maleic acid, tartaric acid, adipic acid, lactic acid, malic acid, malonic acid and mixtures thereof.
[0109] In a preferred embodiment the pH adjuster comprises lactic acid.
[0110] The pH adjuster (f) can be a mixture of two or more pH adjusters, or a single pH adjuster. The preferred weight percentage of the pH adjuster (f) with respect to the total weight of the composition is up to 2 wt %, more preferably 0.5 to 1.5 wt %.
The Composition According to the Invention
[0111] According to a first aspect the present invention provides a concentrated dilutable cleaning composition, comprising:
[0112] (a) one or more anionic surfactants
[0113] (c) one or more non-ionic surfactants comprising one or more polyethoxylated glycerin ester compounds
[0114] (d) an electrolyte
[0115] and optionally
[0116] (b) one or more amphoteric surfactants
[0117] (e) one or more solvents
[0118] (f) one or more pH adjuster agents
[0119] and
[0120] (g) water up to 100 wt % of the composition;
[0121] wherein the total active matter of the composition calculated from the sum of (a), (c), and (b) if present, is from 45 wt % to less than 100 wt %, preferably from 45 wt % to 80 wt %, more preferably from 45 to 60 wt %, even more preferably 47 wt % to 80 wt %, most preferred from 47 wt % to 60 wt %, even most preferred from 50 wt % to 60 wt %, and more preferred from 60 wt % to less than 100 wt % when (b) is not present, and even more preferred from 70 wt % to less than 100 wt % when (b) is not present, taking as a whole the concentrated composition.
[0122] In one embodiment of the invention the composition of the present invention preferably consists of components (a), (c), (d), and (g) optionally together with component (e) and/or (f).
[0123] In a preferred embodiment of the invention the composition of the present invention preferably consists of components (a) to (d), and (g) optionally together with component (e) and/or (f).
In a specially preferred embodiment the composition according to the invention comprises (a), optionally (b), (c), (d), (e), (f) and (g), wherein are:
[0125] (a) is one or more compounds of Formula (I):
[0000] R 1 —O—(CH 2 —CH(R 2 )—O) n (CH 2 CH 2 O) m —SO 3 − (A) 1/z z+ Formula (I)
[0000] wherein R 1 is a linear or branched, saturated or unsaturated alkyl alkenyl chain having from 4 to 30 carbon atoms, R 2 is a C1-C3 linear or branched alkyl chain, A is a suitable countercation, n and m are 0 or an integer number between 1 to 30, and wherein the sum of m+n is from 0 to 30, preferably from 1 to 15 z is 1, 2 or 3.
[0126] (a) which is optionally present, is one or more amphoteric surfactants, preferably one or more amine oxides or one or more betaines
[0127] (b) is one or more non-ionic surfactants comprising one or more polyethoxylated glycerine ester compounds, preferably, the polyethoxylated glycerine ester composition comprising a mixture of compounds of Formula (IV):
[0000]
[0000] wherein each one of m, n, or 1 represents, independently, a number of 0 to 200, the sum of m, n and 1 being in the range of 1 to 200, B being a hydrogen atom or an acyl group represented by —CO—R′, R′ representing a hydrogen, alkyl or alkenyl group, linear or branched, with 3 to 21 carbon atoms, preferably with 5 to 17 carbon atoms, more preferably with 5 to 11 carbon atoms, wherein the mixture comprises the following compounds i. to iv.:
[0128] i. at least one component represented by Formula (IV), wherein, independently, one of the groups B represents an acyl group represented by —CO—R′ and the remaining ones represent H;
[0129] ii. at least one component represented by Formula (IV), wherein, independently, two of the groups B represent an acyl group represented by —CO—R′ and the remaining one represents H;
[0130] iii. at least one component represented by Formula (IV), wherein, independently, each one of the groups B represents an acyl group represented by —CO—R′;
[0131] iv. at least one component represented by Formula (IV), wherein each one of groups B represents H.
[0132] (a) is one or more electrolytes
[0133] (b) is one or more solvents
[0134] (c) is one or more pH adjuster agents
[0135] (d) is water up to 100 wt %,
[0000] wherein the total active matter of the composition calculated from the sum of (a), (b) if present, and (c) is from 45 wt % to less than 100 wt %, preferably from 48 wt % to 80 wt %, most preferred from 50 wt % to 60 wt % taking as a whole the concentrated composition.
[0136] In a further specially preferred embodiment the composition according to the invention comprises (a), (c), (d), and (g) optionally together with component (b) and/or (e) and/or (f), wherein
[0137] (a) is lauryl ether sulfate or a salt thereof
[0138] (b) which is optionally present, is one or more amphoteric surfactants, preferably one or more amine oxides or one or more betaines
[0139] (c) is one or more non-ionic surfactants comprising one or more polyethoxylated glycerine ester compounds, preferably, the polyethoxylated glycerine ester composition comprising a mixture of compounds of Formula (IV):
[0000]
[0000] wherein each one of m, n, or 1 represents, independently, a number of 0 to 200, the sum of m, n and 1 being in the range of 1 to 200, B being a hydrogen atom or an acyl group represented by —CO—R′, R′ representing a hydrogen, alkyl or alkenyl group, linear or branched, with 3 to 21 carbon atoms, preferably with 5 to 17 carbon atoms, more preferably with 5 to 11 carbon atoms, wherein the mixture comprises the following compounds i. to iv.:
[0140] i. at least one component represented by Formula (IV), wherein, independently, one of the groups B represents an acyl group represented by —CO—R′ and the remaining ones represent H
[0141] ii. at least one component represented by Formula (IV), wherein, independently, two of the groups B represent an acyl group represented by —CO—R′ and the remaining one represents H;
[0142] iii. at least one component represented by Formula (IV), wherein, independently, each one of the groups B represents an acyl group represented by —CO—R′;
[0143] iv. at least one component represented by Formula (IV), wherein each one of groups B represents H.
[0144] (a) is one or more electrolytes
[0145] (b) which is optionally present, is one or more solvents
[0146] (c) which is optionally present, is one or more pH adjuster agents
[0147] (d) is water up to 100 wt %,
[0000] wherein the total active matter of the composition calculated from the sum of (a), (c), and (b) if present, is from 45 wt % to less than 100 wt %, preferably from 45 wt % to 80 wt %, more preferably from 45 to 60 wt %, even more preferably 47 wt % to 80 wt %, most preferred from 47 wt % to 60 wt %, even most preferred from 50 wt % to 60 wt %, and more preferred from 60 wt % to less than 100 wt % when (b) is not present, and even more preferred from 70 wt % to less than 100 wt % when (b) is not present, taking as a whole the concentrated composition.
[0148] In a preferred embodiment of the invention the composition contains component (a), (c), and optionally (b), in the following content with respect to the total active matter:
[0149] (a) is from 0.1 to 90 wt %, preferably from 20 to 90 wt %, more preferably from 40 to 85 wt % most preferred from 50 to 85 wt %,
[0150] (c) is from 0.1 to 90 wt %, preferably from 1 to 80 wt %, more preferably from 5 to 30 wt %, most preferred from 5 to 20 wt %,
[0151] (b) if present, is from 0.1 to 65 wt %, preferably from 1 to 65 wt %, more preferably 5 to 40 wt %, most preferred 10 to 30 wt %.
[0152] In a preferred embodiment the total amount of component (d) calculated taking as a whole the concentrated formula is from 0.1 to 20 wt %, preferably from 0.5 to 15 wt %.
[0153] In a preferred embodiment the pH of concentrated composition according to the invention is between 2.5 to 8.5.
[0154] In one embodiment of the invention the pH of the concentrated composition according to the invention is between 2 to 6, more preferably from 3 to 5.
[0155] According to the present invention, preferred embodiments may be combined to provide even more preferred embodiments. For example, a particularly preferred embodiment of component (a) may be combined with a particularly preferred embodiment of component (c), and/or (d), and/or (e), and/or (f); a particularly preferred embodiment of component (a) may be combined with a particularly preferred embodiment of component (b), and/or (c), and/or (d), and/or (e), and/or (f); a particularly preferred embodiment of component (b) may be combined with a particularly preferred embodiment of component (a), and/or (c), and/or (d), and/or (e), and/or (f); a particularly preferred embodiment of component (c) may be combined with a particularly preferred embodiment of component (a), and/or (d), and/or (e), and/or (f); a particularly preferred embodiment of component (c) may be combined with a particularly preferred embodiment of component (a), and/or (b), and/or (d), and/or (e), and/or (f); a particularly preferred embodiment of component (d) may be combined with a particularly preferred embodiment of component (a), and/or (c), and/or (e), and/or (f); a particularly preferred embodiment of component (d) may be combined with a particularly preferred embodiment of component (a), and/or (b), and/or (c), and/or (e), and/or (f); a particularly preferred embodiment of component (e) may be combined with a particularly preferred embodiment of component (a), and/or (c), and/or (d), and/or (f); a particularly preferred embodiment of component (e) may be combined with a particularly preferred embodiment of component (a), and/or (b), and/or (c), and/or (d), and/or (f); a particularly preferred embodiment of component (f) may be combined with a particularly preferred embodiment of component (a), and/or (c), and/or (d), and/or (e) and a particularly preferred embodiment of component (f) may be combined with a particularly preferred embodiment of component (a), and/or (b), and/or (c), and/or (d), and/or (e).
[0156] In a preferred embodiment, the concentrated dilutable cleaning composition according to the invention has a viscosity at 20° C. which is a viscosity below 500 cps, preferably below 300 cps, and more preferably below 250 cps.
[0157] According to a second aspect the present invention provides a diluted cleaning composition prepared upon dilution with water of the concentrated composition according to the invention.
[0158] According to a third aspect the present invention provides a medium diluted cleaning composition with a total active matter from more than 20 to 35 wt % prepared from dilution with water of a concentrated composition according to the invention.
[0159] In a preferred embodiment, the medium diluted cleaning composition with a total active matter from more than 20 to 35 wt % according to the invention has a viscosity at 20° C. which is a viscosity in the range of 300 cps to 3500 cps, preferably in the range of 500 cps to 3000 cps, more preferably in the range of 600 cps to 2000 cps.
[0160] According to a fourth aspect the present invention provides a highly diluted cleaning composition with a total active matter from more than 5 to less than 20 wt % prepared from dilution with water of a concentrated composition according to the invention.
[0161] In a preferred embodiment, the highly diluted cleaning composition with a total active matter from more than 5 to less than 20 wt % according to the invention has a viscosity at 20° C. which is a viscosity in the range of 200 cps to 3500 cps, preferably in the range of 300 cps to 2000 cps, more preferably in the range of 400 cps to 1200 cps.
[0162] In one preferred embodiment the concentrated composition according to the invention has a pH in the range of 6 to 14, preferably in the range of 6 to 8.
[0163] In another preferred embodiment the concentrated composition according to the invention has a pH in the range of 2 to less than 6.
[0164] In one preferred embodiment the diluted cleaning composition has a pH in the range of 6 to 14, preferably in the range of 6 to 8.
[0165] In another preferred embodiment the diluted cleaning composition has a pH in the range of 2 to less than 6.
[0166] In one preferred embodiment the medium diluted cleaning composition has a pH in the range of 6 to 14, preferably in the range of 6 to 8.
[0167] In another preferred embodiment the medium diluted cleaning composition has a pH in the range of 2 to less than 6.
[0168] In one preferred embodiment the highly diluted cleaning composition has a pH in the range of 6 to 14, preferably in the range of 6 to 8.
[0169] In another preferred embodiment the highly diluted cleaning composition has a pH in the range of 2 to less than 6.
[0170] According to a fifth aspect the present invention provides a cleaning composition with a controlled viscosity profile that is satisfactory for the consumer, and wherein the concentrated dilutable cleaning composition according to the invention has a viscosity at 20° C., which is a low viscosity that is in a range which is usable for the consumer, and wherein the medium diluted cleaning composition obtained upon diluting the concentrated cleaning composition has a higher viscosity than the concentrate and which is a viscosity that is controlled to be in a range which is satisfactory for the consumer; and wherein the highly diluted cleaning composition obtained upon diluting the concentrated cleaning composition and/or the medium diluted cleaning composition has a maintained high or reduced viscosity with respect to the medium diluted cleaning composition which is a viscosity that is controlled to be in a range which is satisfactory for the consumer, preferably in the range of 200 cps-3500 cps.
[0171] In a preferred embodiment, the present invention provides a cleaning composition with a viscosity profile that is satisfactory for the consumer, and wherein the concentrated dilutable cleaning composition according to the invention has a viscosity at 20° C., which is a viscosity below 500 cps, preferably below 300 cps, more preferably below 250 cps; and wherein the medium diluted cleaning composition obtained upon diluting the concentrated cleaning composition has a total active matter from more than 20 to 35 wt %, and wherein the medium diluted cleaning composition has a viscosity at 20° C. which is a viscosity in the range of 300 to 3500 cps, preferably in the range of 500 cps to 3000 cps, more preferably in the range from 600 to 2000 cps; and wherein the highly diluted cleaning composition obtained upon diluting the concentrated cleaning composition and/or the medium diluted cleaning composition has a total active matter from more than 5 to 20 wt %, and wherein the highly diluted cleaning composition has a viscosity at 20° C. which is a viscosity in the range of 200 cps to 3500 cps, preferably in the range of 300 cps to 2000 cps, more preferably in the range from 400 to 1200 cps.
[0172] According to a sixth aspect the present invention provides a method to prepare a concentrated dilutable composition according to the invention.
[0173] According to a seventh aspect the present invention provides a method to prepare a diluted composition, a medium diluted composition or a highly diluted composition according to the invention.
[0174] In another aspect, the present invention provides a method to prepare a concentrated, a diluted, a medium diluted or a highly diluted cleaning composition according to the invention as hereinabove defined.
[0175] The concentrated dilutable compositions according to the invention can be prepared by dissolving the components (a), (c) and (d) and optionally (b), (e) and (f) in water, preferably under stirring and heating.
[0176] The diluted composition is preferably prepared by diluting the concentrated composition with water such as tap water; the medium diluted composition is preferably prepared by diluting the concentrated or a diluted composition with water such as tap water, the highly diluted composition is preferably prepared by diluting the concentrated or a diluted or medium diluted composition with water such as tap water.
A Cleaning Method According to the Invention
[0177] According to a further aspect, the present invention provides a method of cleaning comprising contacting said surface with a concentrated, a diluted, a medium diluted or a highly diluted cleaning composition as hereinbefore defined.
[0178] According to a further aspect, the present invention provides a method of cleaning comprising using a composition according to the invention.
[0179] According to an additional aspect the present invention provides a method of manual dishwashing using a composition according to the invention.
[0180] The compositions according to the invention are especially suitable for manual dishwashing although the compositions according to the invention could be used for hard surface cleaning or cleaning in general. The compositions according to the invention might be directly applied to the treated surface or could be used by being applied in a sponge, towel or other porous or any meshed suitable device.
[0181] According to a further additional aspect the present invention provides a foam generated from a dilution and mixture with air of a composition according to the invention.
[0182] Preferably the method to generate a foam cleaner using a composition according to the invention comprises the steps herein below defined. To apply the composition according to the invention over a surface a suitable foam generator device is used. The dilution of the composition according to the invention can be made prior to use or at the very moment of the application, meaning that the foaming generator device might includes a system that allows the composition according to the invention to be introduced at relatively high concentration and to be diluted to the suitable concentration for foam generation. Usually the foam generator device delivers the foam to a container and the foam is pumped to and put in contact with the surface to be treated.
Additives to the Composition According to the Invention
[0183] The composition according to the invention can comprise other components aimed to improve any technical aspect of the composition like the stability, the cleaning ability or the sensorial aspects related to the consumer perception.
Cationic Surfactants
[0184] Examples of cationic surfactants are alkyl benzyl dimethyl ammonium halides, alkyl trimethyl ammonium halides, alkyl hydroxyethyl ammonium halides, quaternized ethoxylated amines, esterquats derived from triethanolamine, methyldiethanolamine, dimethylaminopropanediol, oligomers of said esterquats and the like and mixtures thereof.
Disinfecting Agents
[0185] The cleaning composition according to the invention can comprise disinfecting agents in order to improve the disinfection ability of the surfaces to be treated. Suitable disinfecting agents according to the invention include any organic or inorganic compounds with antimicrobial activity. Examples of suitable antimicrobial agents according to the invention are phenols and derivatives; organic and inorganic acids, their esters and salts (acetic acid, propionic acid, undecanoic acid, sorbic acid, lactic acid, benzoic acid, salicylic acid, dehydroacetic acid, sulphur dioxide, sulphites, bisulphites); alcohols (ethanol, iso-propanol, n-propanol, methanol, benzyl alcohol, etc) and peroxides (hydrogen peroxide, peracetic acid, benzoyl peroxide, sodium perborate, potasium permanganate, etc.), aldehydes (formaldehyde, glutaraldehyde, glyoxal); quaternary ammonium compounds-quats (benzalconium chloride, cetylpiridinium chloride, didecyldimethylammonium chloride, etc); chlorine based derivatives such as chloramines, dichloroisocianurates, chloroform and chlorine releasing compounds (i.e: sodium hypochlorite); Iodine based compounds (free iodine, iodophors and iodoform); metals and salts (cadmium, silver, copper, etc). The selection of the suitable disinfecting agent can be made by the skilled in the art taking into consideration the specific characteristics of the target use of the composition according to the invention.
Sequestering/Chelating Agents of the Invention
[0186] The cleaning composition according to the invention can comprise organic or inorganic substance which could contribute to pH adjustment though main purpose is to contain the effects of water hardness on surfactants activity detriment. Examples of sequestering/chelating agents suitable for the composition according to the invention include hydroxides, carbonates, bicarbonates, silicates, borates, zeolites, citrates, polycarboxylates, EDTA, nitrilotriacetate, phosphonic acid, phosphonic acid derivatives, for instance those commercialized under the brandname DEQUEST available from Monsanto, phosphates and complex phosphates like polyphosphates and the like, and mixtures thereof.
Preservatives
[0187] The composition according to the invention can comprise certain amounts of preservatives or biocides in order to prevent biological degradations at certain conditions. Examples of suitable preservatives for the composition according to the invention include 1,2-benzisothiazol-3-one; Benzyl alcohol; 5-bromo-5-nitro-1,3-dioxane; 2-bromo-2-nitropropane-1,3-diol; Chloroacetamide; Diazolinidylurea; Formaldehyde; Glutaraldehyde; Guanidine, hexamethylene-, homopolymer; CMI+MIT in mixture 3:1 [5-chloro-2-methyl-4-isothiazolin-3-one]+[2-methyl-4-isothiazolin-3-one]; 2-methyl-2H-isothiazol-3-one (MIT); Methyldibromoglutaronitrile; e-phtaloimidoperoxyhexanoic acid; methyl-, ethyl- and propylparaben; o-phenylphenol; sodium benzoate; sodium hydroxy methyl glycinate; sodium nitrite; triclosan; phenoxy-ethanol.
Perfumes, Colorant, Dyes or Other Sensorial Improvers
[0188] The composition according to the invention might contain certain amounts of perfumes, fragrances, colorants or dyes or other components intended to improve its appearance or the sensorial experience of the user of the composition or intended to solve some practical matter like to enable the visual detection of the presence of the composition according to the invention.
[0189] Examples of suitable fragrances according to the invention include aldehydes, esters, ketones and the like.
[0190] The aldehydes useful in the present invention can be one or more of, but not limited to, the following group of aldehydes: phenylacetaldehyde, p-methyl phenylacetaldehyde, p-isopropyl phenylacetaldehyde, methylnonyl acetaldehyde, phenylpropanal, 3-(4-t-butylphenyl)-2-methyl propanal, 3-(4-t-butylphenyl)-propanal, 3-(4-methoxyphenyl)-2-methylpropanal, 3-(4-isopropylphenyl)-2-methylpropanal, 3-(3,4-methylenedioxyphenyl)-2-methylpropanal, 3-(4-ethylphenyl)-2,2-dimethylpropanal, phenylbutanal, 3-methyl-5-phenylpentanal, hexanal, trans-2-hexenal, cis-hex-3-enal, heptanal, cis-4-heptenal, 2-ethyl-2-heptenal, 2,6-dimethyl-5-heptenal (melonal), 2,6-dimethylpropanal, 2,4-heptadienal, octanal, 2-octenal, 3,7-dimethyloctanal, 3,7-dimethyl-2,6-octadien-1-al, 3,7-dimethyl-1,6-octadien-3-al, 3,7-dimethyl-6-octenal, 3,7-dimethyl-7-hydroxyoctan-1-al, nonanal, 6-nonenal, 2,4-nonadienal, 2,6-nonadienal, decanal, 2-methyl decanal, 4-decenal, 9-decenal, 2,4-decadienal, undecanal, 2-methyldecanal, 2-methylundecanal, 2,6,10-trimethyl-9-undecenal, undec-10-enyl aldehyde, undec-8-enanal, dodecanal, tridecanal, tetradecanal, anisaldehyde, bourgenonal, cinnamic aldehyde, α-amylcinnam-aldehyde, α-hexyl cinnamaldehyde, methoxy cinnamaldehyde, citronellal, hydroxy-citronellal, isocyclocitral, citronellyl oxyacet-aldehyde, cortexaldehyde, cumminic aldehyde, cyclamem aldehyde, florhydral, heliotropin, hydrotropic aldehyde, lilial, vanillin, ethyl vanillin, benzaldehyde, p-methyl benzaldehyde, 3,4-dimethoxybenzaldehyde, 3- and 4-(4-hydroxy-4-methyl-pentyl)-3-cyclohexene-1-caroxaldehyde, 2,4-dimethyl-3-cyclohexene-1-carboxaldehyde, 1-methyl-3-4-methylpentyl-3-cyclohexencarboxaldehyde, and p-methylphenoxyacetaldehyde.
[0191] Examples of ketones useful in the present invention can be one or more of, but not limited to, the group of following ketones: α-damascone, β-damascone, δ-damascone, β-damascenone, muscone, 6,7-dihydro-1,1,2,3,3-pentamethyl-4(5H)-indanone, cashmeran, cis-jasmone, dihydrojasmone, methyl dihydrojasmonate, α-ionone, β-ionone, dihydro-β-ionone, γ-methyl ionone, α-iso-methyl ionone, 4-(3,4-methylenedioxyphenyl)butan-2-one, 4-(4-hydroxyphenyl)butan-2-one, methyl β-naphthyl ketone, methyl cedryl ketone, 6-acetyl-1,1,2,4,4,7-hexamethyltetralin (tonalid), 1-carvone, 5-cyclohexadecen-1-one, acetophenone, decatone, 2-[2-(4-methyl-3-cyclohexenyl-1-yl)propyl]cyclopentan-2-one, 2-sec-butylcyclohexanone, β-dihydro ionone, allyl ionone, α-irone, α-cetone, α-irisone, acetanisole, geranyl acetone, 1-(2-methil-5-isopropyl-2-cyclohexenyl)-1-propanone, acetyl diisoamylene, methyl cyclocitrone, 4-t-pentyl cyclohexanone, p-t-butylciclohexanone, o-t-butylcyclohexanone, ethyl amyl ketone, ethyl pentyl ketone, menthone, methyl-7,3-dihydro-2H-1,5-benzodioxepine-3-one, fenchone, methyl naphthyl ketone, propyl naphthyl ketone and methyl hydroxynaphthyl ketone.
Hydrotopes
[0192] The composition according to the invention might comprise certain amounts of one ore more hydrotopes intended to enhance the solubility of certain substances. Examples of suitable hydrotopes to be used in the composition according to the invention are p-toluene sulfonates, xylene sulfonates and cumene sulfonates, preferably in the form of their calcium, potassium, sodium or ammonium salts.
[0193] If the compositions according to the invention are used for manual dishwashing, preferable additives can be selected from the list above. However, the compositions according to the invention could be used in different applications. In this regard, the suitable additives could include also other components like corrosion inhibitors, polymers, natural oils, silicones, fluorescent whitening agents, photo-bleaches, fiber lubricants, reducing agents, enzymes, enzyme stabilizing agents, powder finishing agents, builders, bleaches, bleach catalysts, soil release agents, dye transfer inhibitors, buffers, colorants, fragrances, pro-fragrances, rheology modifiers, anti-ashing polymers, soil repellents, water-resistance agents, suspending agents, aesthetic agents, structuring agents, sanitizers, solvents, fabric finishing agents, dye fixatives, fabric conditioning agents, deodorizers, etc.
[0194] The following examples are given in order to provide a person skilled in the art with a sufficiently clear and complete explanation of the present invention, but should not be considered as limiting of the essential aspects of its subject, as set out in the preceding portions of this description.
EXPERIMENTAL SECTION
1. Concentrated Dilutable Compositions According to the Invention: Preparation, Dilution and Characteristics
[0195] Table 1 summarizes the components of the concentrated compositions according to the invention (Examples 1-7) and comparative examples (Comparative Examples 1-7).
[0196] Concentrated compositions are prepared at room temperature introducing in a laboratory baker the suitable quantity of each one of the components detailed in the Table 1 in order to have the active matter contents indicated therein. The mixture containing all the components is stirred until complete homogenization. pH is measured in the concentrated formula, as it is, with a CRISON micropH 2001 pH-meter.
[0197] Table 2 summarizes the appearance, viscosity, pH and dilution ability characteristics of the concentrated compositions described in Table 1.
[0198] The dilution ability is measured during the preparation of the diluted compositions as follows. A suitable quantity of the concentrated composition is introduced in a glass bottle. Then the appropriate amount of water is added to the bottle. The mixture is manually shaken for 20 seconds. Then the mixture is allowed to equilibrate at room temperature. The time needed to observe the diluted composition exhibits a homogeneous aspect, this is without observing gel lumps or foam, is the parameter that characterizes the dilution ability. The lower the time observed the better the dilution ability.
[0199] In Table 2, diluted formulations noted as “2×” correspond to medium diluted compositions and are prepared by mixing 1 part per weight of concentrated formula and 1 part by weight of water. Correspondingly, diluted formulations noted as “3×” corresponds to highly diluted compositions and are prepared by mixing 1 part by weight of concentrated formula with 2 parts by weight of water.
[0200] Appearance is visually assessed at room temperature, for the concentrated and for the diluted formulas.
[0201] Viscosity is measured at 20° C. using a Brookfield LV viscometer, the appropriate spindle type and speed (rpm) combinations (spindle/rpm) are chosen following the instructions of the Brookfield devices. If not indicated otherwise, the viscosity of the concentrated dilutable cleaning compositions is measured with a spindle/speed combination of 1/6 (spindle/rpm) at 20° C., whereas the viscosity of the diluted cleaning compositions including the medium diluted and highly diluted cleaning compositions is measured with a spindle/speed combination of 2/6 (spindle/rpm) at 20° C.
[0202] Table 3 summarizes the foaming power (the ability to generate foam) of the different diluted compositions evaluated using a SITA Foam Tester R-2000 (by SITA Messtechnik GmbH). The foaming power is determined for a diluted composition at a concentration of 0.012 active matter wt % prepared using hard water (20° HF (544 ppm Ca 2+ and 156 ppm Mg 2+ ). The reason for doing the test using a composition of that low active matter is to observe the behavior of the composition at similar conditions to those occurring in real hand-dishwashing. The foaming power is evaluated in the absence and in the presence of olive oil. The reason for adding olive oil is to evaluate the foaming power in the present of fats. The foaming power is expressed as the maximum foam volume observed during the test. The test consists in the repetition of 50 cycles each one including the following steps:
[0000] Foam Power Measurement without Oil
[0203] Stirring cycle of 10 s at 1500 rpm
[0204] Observation of foam volume
[0000] Foam Power Measurement with Oil
[0205] Adding 50 μL of olive oil
[0206] Stirring cycle of 10 s at 1500 rpm
[0207] Observation of foam volume
[0208] The test is carried out at a temperature of 40° C. The purpose of the test is to show the foaming power of the diluted compositions according to the invention is equal or even better to that of comparative examples.
[0209] Cleaning ability is assessed using IKW Recommendation for the Quality Assessment of the Cleaning Performance of Hand Dishwashing detergents, published in SÖFW-Journal, 128, Jahrgang 5-2002. Cleaning ability corresponds to the number of cleaned dishes, soiled with IKW soil 1. The cleaning ability of a diluted composition according to the invention and of a commercial product is compared in Table 4. The results show that the performance of the diluted compositions according to invention is good.
[0000]
TABLE 1
Concentrated compositions
[wt %]
calculated taking the sum of (a) + (b) + (c) as a whole
[wt %]
component (b)
component (c)
calculated in respect of the total composition
component (a)
(amphoteric
(non-ionic
component (d)
component (e)
component (f)
Active
(lauryl ether sulfate)
surfactants)
surfactant)
(electrolytes)
(Ethanol)
(Citric acid)
Matter
pH
Example 1
60
20 (1)
20 (3)
4.8 (MgCl 2 )
9.6
0.5
47.9
6.5
Example 2
70
20 (1)
10 (3)
3.5 (MgCl 2 )
6.5
0.5
48.4
6.1
Example 3
75
20 (1)
5 (3)
1.8 (NaCl)
10
1.5
45.1
5.5
Example 4
80
10 (1)
10 (3)
5.1 (MgCl 2 )
9.1
0.5
51.3
5.9
Example 5
70
20 (1)
10 (3)
3.2 (MgCl 2 )
10
0.5
46.9
3.2
Example 6
70
20 (2)
10 (4)
3.5 (MgCl 2 )
9.5
0.5
48.4
6.0
Example 7
70
20 (2)
10 (4)
3.2 (MgCl 2 )
10
0.5
46.9
3.2
Comparative
70
30 (1)
0
2.5 (NaCl)
10
0.5
45.6
6.5
Example 1
Comparative
70
20 (1)
10 (5)
3.5 (MgCl 2 )
9.5
0.5
48.4
6.0
Example 2
Comparative
70
20 (1)
10 (6)
3.5 (MgCl 2 )
9.5
0.5
47.3
6.0
Example 3
Comparative
70
20 (1)
10 (7)
3.5 (MgCl 2 )
9.5
0.5
45.7
6.1
Example 4
Comparative
78
22 (b 1 )
0
3.2 (MgCl 2 )
10
0.5
44.7
3.1
Example 5
Comparative
70
20 (b 1 )
10 (8)
3.2 (MgCl 2 )
10
0.5
46.9
3.2
Example 6
Comparative
70
20 (b 1 )
10 (7)
3.2 (MgCl 2 )
10
0.5
44.3
3.0
Example 7
(X) stands for:
(1) cocoamidopropyl amine oxide
(2) cocoamidopropyl betaine
(3) capric/caprylic glycerin ester ethoxylated with 7 EO mols
(4) cocoate glycerin ester ethoxylated with 7 EO mols
(5) C 13 /C 15 alcohol ethoxylated with 7 EO mols
(6) C 8 /C 10 alkylpolyglucoside
(7) C 12 /C 14 alkylpolyglucoside
(8) C 9 -C 11 alcohol ethoxylated with 7 EO mols
[0000]
TABLE 2
Properties of the dilutions obtained from the concentrated compositions described in Table 1
Concentrated
Medium diluted compositions
Highly diluted compositions
compositions
“2X”
“3X”
Viscosity
Viscosity
Dilution
Active
Viscosity
Dilution
[cps]
Active Matter
[cps]
ability [h]
Matter
(cps)
ability [h]
Example 1
143
23.9
595
<1
16
425
<1
Example 2
220
24.2
1785
<1
16.1
950
<1
Example 3
141
22.6
1980
<1
15.0
595
<1
Example 4
184
25.7
1635
<1
17.1
830
<1
Example 5
160
23.5
1765
<1
15.6
815
<1
Example 6
229
24.2
2974
<1
16.1
3214
<1
Example 7
147
23.5
2895
<1
15.6
1590
<1
Comparative
>100000
(* 1 )
22.8
4894
(* 2 )
24
15.2
130
(* 3 )
24
Example 1
Comparative
242
24.2
3029
2
16.1
3989
2
Example 2
Comparative
290
23.7
2245
24
15.8
840
24
Example 3
Comparative
316
22.9
5279
(* 2 )
4
15.2
6139
4
Example 4
Comparative
35
(* 3 )
22.4
7000
( * 2 )
2
14.9
(**)
(**)
Example 5
Comparative
205
23.5
3579
2
15.6
3329
2
Example 6
Comparative
248
22.2
6459
(* 2 )
2
14.8
7058
(* 2 )
2
Example 7
(**) not homogeneous aspect, separate formula
Viscosity measurement at 20° C. carried out with (spindle/rpm) combination of:
(* 1 ) used 4/3;
(* 2 ) used 3/6;
(* 3 ) used 1/6
[0000]
TABLE 3
Foaming Power
Maximum Volume Foam
Maximum Volume Foam
(mL)
(mL)
without oil
with oil
Example 2
465
231
Example 4
470
267
Example 5
475
277
Example 6
447
261
Comparative
400
221
Example 2
Comparative
440
260
Example 4
[0000]
TABLE 4
Cleaning Ability
SITA with oil
IKW1
Example 2
231
19
Commercial Product (*)
216
17
(*) Fairy (Procter&Gamble)
[0210] It can be seen that compositions according to the invention provide formulations with suitable viscosity profiles and are more feasible dilutable than comparative examples.
[0211] The foaming behavior and the cleaning performance is adequate making the compositions according to the invention suitable for dishwashing. | Disclosed are aqueous, concentrated dilutable liquid cleaning compositions comprising one or more anionic surfactants, one or more non-ionic surfactants, and an electrolyte, preferably in combination with one or more amphoteric surfactants, having a total active matter higher than 45 wt % based on the sum of the surfactants above that exhibit a controllable viscosity profile that is satisfactory to the consumer while being easy to dilute, providing fast enough a diluted, a medium diluted or a highly diluted cleaning composition. | 2 |
BACKGROUND
As network operators and service providers strive to provide new or improved services and/or assets to users, network requirements may correspondingly increase. As a result, network operators and service providers must confront a host of challenges to ensure that quality of service (QOS) and other performance metrics are maintained. For example, one important challenge confronted by network operators and service providers is to ensure that service is not degraded or minimally degraded due to failures in the network.
Protection path(s) can be used to maintain end-to-end services when a network failure event occurs. The protection path(s) for a service can be pre-provisioned statically or generated dynamically in response to a network failure event.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram illustrating an exemplary environment in which in which exemplary embodiments may be implemented;
FIG. 2 is a diagram illustrating exemplary components of a device that may correspond to one or more devices in the exemplary environment depicted in FIG. 1 ;
FIG. 3 is a flowchart of an exemplary process for simulating a network model according to an exemplary embodiment of a Stratified-Dynamic Path Failure Importance Sampling (DPFS) algorithm;
FIGS. 4A and 4B are flowcharts of an exemplary process for simulating a network model according to an exemplary embodiment of an Adaptive Stratified-DPFS algorithm;
FIG. 5 is a flowchart of an exemplary process for simulating a network model according to an exemplary embodiment of a Path Group Failure Importance Sampling (PGFS) algorithm;
FIG. 6 is a flowchart of an exemplary process for simulating a network model according to an exemplary embodiment of the Stratified-PGFS algorithm; and
FIGS. 7A and 7B are flowcharts of an exemplary process for simulating a network model according to an exemplary embodiment of the Adaptive Stratified-PGFS algorithm.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The following detailed description refers to the accompanying drawings. The same reference numbers in different drawings may identify the same or similar elements. Also, the following detailed description does not limit the invention.
The term “network,” as used herein, is intended to be broadly interpreted to include a wireless network and/or a wired network. The network may have, for example, a mesh topology, a star topology, a fully-connected topology, or some other type of topology. The term “node,” as used herein, is intended to be broadly interpreted to include a network device having routing or switching capability. For example, the node may correspond to a router, a switch, a bridge, a gateway, a computer, a server, etc.
The term “path,” as used herein, is intended to be broadly interpreted to include a physical path and/or a logical path. For example, a path may correspond to an Internet Protocol (IP) path, a Multi-Protocol Label Switching (MPLS) path, a light (i.e., optical) path, a virtual circuit path, or any combination thereof. The path may correspond to an end-to-end path (e.g., from a source to a termination).
A simulation technique called Dynamic Path Failure Importance Sampling (DPFS) was developed for the Markov Monte Carlo simulation of path availability in mesh networks having dynamic path restoration. DPFS is described in detail in A. E. Conway, “Fast Simulation of Service Availability in Mesh Networks with Dynamic Path Restoration,” IEEE/ACM Transactions on Networking, Jul. 12, 2010, and in U.S. Patent Application Publication No. 20100232299, which are incorporated in their entirety herein. In DPFS, the failure rates of network elements are biased at increased rates until path failures are observed under an assumed dynamic path rerouting algorithm.
The exemplary embodiments described herein pertain to modifications of the DPFS algorithm. A first modification of the DPFS algorithm is called Stratified-DPFS. In a network, the unavailability of one or multiple end-to-end paths may be higher relative to other end-to-end path(s). In fact, there may be orders of magnitude differences between end-to-end paths. As a result, some path failures may not be sampled during a simulation with DPFS, at least not without an excessive number of simulation regenerations. According to an exemplary embodiment, in Stratified-DPFS, the transition rates (e.g., failures rates and/or repair rates) may be biased at increased rates or decreased rates until a particular chosen path failure is observed under rerouting.
A second modification to the DPFS algorithm is called Adaptive Stratified-DPFS. In Stratified-DPFS, the number of simulation regenerations used in the biasing for each path is made equal. In Adaptive Stratified-DPFS, the number of simulation regenerations used in the biasing for a path is adapted based on an observed sample coefficient of variation of the path unavailability. In this way, the sampling of all path failures is more likely to occur during a simulation. For example, a path that has an intrinsically higher unavailability sample variance may be subjected to more simulation regenerations than a path that has an intrinsically lower unavailability sample variance.
Other variations of the DPFS algorithm may be designed specifically for networks that use groups of static, pre-provisioned protection paths for end-to-end service protection. A first modification of DPFS is called Path Group Failure Importance Sampling (PGFS). In PGFS, the transition rates of links are biased at increased rates or decreased rates until a path group failure is observed. A second modification and a third modification are called Stratified-PGFS and Adaptive Stratified-PGFS. In Stratified-PGFS, the transition rates may be biased at an increased rate or a decreased rate until a particular path group failure is observed under rerouting. In Adaptive Stratified-DPFS, the number of simulation regenerations used in the biasing for each path group is adapted based on an observed sample coefficient of variation of the path group availability.
FIG. 1 is a diagram illustrating an exemplary environment 100 in which exemplary embodiments may be implemented. As illustrated in FIG. 1 , exemplary environment 100 may include a mesh network 105 that includes nodes 110 - 1 through 110 -X (referred to as nodes 110 or individually as node 110 ), links 115 - 1 through 110 -Z (referred to as links 115 or individually as link 115 ), and user device 120 .
The number of devices and configuration in environment 100 is exemplary and provided for simplicity. According to other embodiments, environment 100 may include additional devices, fewer devices, different devices, and/or differently arranged devices than those illustrated in FIG. 1 . Environment 100 may include wired and/or wireless connections among the devices illustrated.
Mesh network 105 may include one or multiple networks of one or multiple types. Nodes 110 may include a network device having routing or switching capability. Links 115 may include connections or communication paths between nodes 110 .
User device 120 may include a computational device. For example, user device 120 may correspond to a computer or a server, which may reside inside or outside of mesh network 105 . User device 120 may include an application (e.g., a Stratified-DPFS application, an Adaptive Stratified-DPFS application, a PGFS application, a Stratified-PGFS application, and/or an Adaptive Stratified-PGFS application) to provide network simulation(s) according to the exemplary embodiments of the algorithms described. By way of example, the application may be implemented as a text-based simulation environment (e.g., Visual Basic, ns-2, ns-3, MATLAB, Octave, Python, Comsol Script, MATRIX, Mathcad, Maple, C++, C, JAVA, etc.) a graphically-based simulation environment (e.g., Simulink, Simflow, VisSim, LabView), or a hybrid simulation environment that includes text-based and graphical-based environments.
With reference to FIG. 1 , according to an exemplary process, user device 120 may receive network topology information pertaining to mesh network 105 and initialization information for executing one of the Stratified-DPFS application, the Adaptive Stratified-DPFS application, the PGFS application, the Stratified-PGFS application, or the Adaptive Stratified-PGFS application. Depending on the application executed, user device 120 may simulate mesh network 105 , and calculate, among other things, mean estimates of average times for path or path group unavailabilities and estimates of unavailability of paths or path groups, as described further below. The estimates may be output (e.g., as a file, displayed, etc.) to a user. The user may use this information for assessing service availability, etc., as such factors pertain to mesh network 105 .
According to exemplary embodiments, mesh network 105 may be formulated in terms of nodes, links, circuits, and paths. A unidirectional circuit traverses one or more unidirectional links. A unidirectional path traverses one or more unidirectional circuits. Mesh network 105 may include L unidirectional point-to-point links. The bandwidth of a link x is denoted by B link (x) bits/second. A link can be in an operational state or a failed state. A failed link has no available bandwidth. The instantaneous available bandwidth of a link x at a time t is denoted by B link (x,t) with initial condition B link (x,0)=B link (x). A bidirectional link can be modeled using a pair of unidirectional links.
A circuit is defined to be a unidirectional connection between two nodes 110 over a set of interconnected links 115 . The total number of circuits in mesh network 105 is denoted by C. The total bandwidth in a circuit i is denoted by B circuit (i) bits/second. The circuit i consumes the bandwidth B circuit (i) in each link of circuit i. The circuit routing matrix is defined to be C=[c ix : 1≦i≦C, 1≦x≦L], in which c ix =1 if circuit i uses link x, and 0 otherwise. The circuit routing matrix C is static in time. A link may be used by more than one circuit. The bandwidth of a circuit is less than or equal to the bandwidth of any of the links that the circuit uses, i.e., B circuit (i)≦Min {B link (x)|c ix =1, 1≦x≦L}. The sum of the bandwidths of the circuits that use link x is less than or equal to the link bandwidth B link (x). If a circuit uses a link that is in a failed state, then the circuit is considered to be in a failed state with no available bandwidth. An instantaneous available bandwidth of circuit i at time t is denoted by B circuit (i,t), in which B circuit (i,t)≦Min {B link (x,t)|c ix =1, 1≦x≦L}, with initial condition B circuit (i,0)=B circuit (i). A bidirectional circuit is modeled using a pair of unidirectional circuits. The two directions of a bidirectional circuit can have different routes over the links of the network
A path is defined to be a unidirectional end-to-end connection between two nodes 110 over a set of interconnected circuits. The total number of paths is denoted by P. The required bandwidth of a path i is denoted by B path (i) bits/second. A path consumes the bandwidth B path (i) in each of the circuits that it uses. A circuit may be used by more than one path.
In the case of dynamic path restoration, the routing of a particular path in terms of working circuits may change in time as circuit failures occur due to link failures and paths are rerouted. The state of the path routing at a time t is given by a time-varying path routing matrix P(t)=[p ic (t):1≦i≦P, 1≦c≦C], in which p ic (t)=1 if a path i uses a circuit c at time t, and 0 otherwise. The routing of all paths is subject to the available bandwidth of each circuit. The initial path matrix P(0) is assumed to be given. If a working route for a path cannot be found, then the path is no longer operational. Let A(i,t)=1 if path i is operational at time t, and 0 otherwise, with the initial condition A(i,0)=1 for 1≦i≦P.
In the case of groups of static protection paths, the path routing is given by a static path routing matrix P=[p ic :1≦i≦P, 1≦c≦C], in which p ic =1 if a path i uses a circuit c, and 0 otherwise. The paths may be fully disjoint or partially linked-disjoint. In the case of partial disjointedness, different paths may have some circuits in common. The static paths are assigned to S groups. Each path is assigned to one particular group. The number of paths in a group s is denoted by N(s). The path group s is operational if at least one of the paths in group s is operational, otherwise it is not operational. If N(s)=1, then paths is an unprotected path.
A failure equivalence group (FEG) is defined to be a particular subset of unidirectional links together with an associated failure and repair process in mesh network 105 . A particular link may belong to one or more FEGs. During any instance in time, each FEG is in either an operational state or a failed state. When a FEG is in a failed state, all of the unidirectional links in the FEG are unusable. A unidirectional link is useable, if and only if all other unidirectional links in the FEG, to which the unidirectional link belongs, are operational. Each FEG experiences the arrival of failure events that cause the FEG to be in a failed state. The failure events in a particular FEG are repaired by a finite or an infinite pool of repair personnel that is dedicated to the FEG. When a FEG is operational and a failure event arrives to the FEG, the FEG enters the failed state and the repair of the failure event is started by a repair person. While in the failed state, the FEG may also experience additional independent arrivals of failure events. The additional failure events may be repaired by additional repair persons in parallel or placed in a repair queue. In general, the failure and repair process for each FEG is modeled as a dedicated finite source, multi-server queue or an infinite source, multi-server queue, with the number of servers corresponding to the population of the repair personnel associated with the FEG. Whenever the repair of all outstanding failure events in the FEG has been completed, the FEG re-enters the operational state. The FEG construct enables the modeling of bidirectional link failures/repairs, multiple simultaneous cuts in series along particular unidirectional or bidirectional links, the failure/repair of in-line optical fiber amplifiers, node failures, geographically distributed physical failure events, and preventative maintenance.
The number of FEGs in the network mesh 105 is denoted by G. The failure and repair processes of the FEG are assumed to be independent and Markovian. The failure arrival process of a FEG may correspond to either an infinite source or a finite source. The maximum possible number of failure events in FEG g is K g . In the case of an infinite source, the failure event arrival rate of FEG g is λ g and K g =∞. In the case of a finite source, the number of sources is K g and the arrival rate for each source is λ g . The repair rate of a group g failure, by a repair person, is μ g . Let μ g =λ g /μ g .
The state of the FEG at time t is given by the random variable N(t)=(N 1 (t), . . . , N G (t))), in which N g (t) is the number of FEG g failure events at time t that have not been repaired. If N g (t)=0, then FEG g is in the operational state, otherwise it is in the failed state. The number of repair personnel associated with FEG g is R g . The FEG failure and repair process forms a continuous-time Markov chain with state-space F={n|n=(n 1 , . . . , n G ), 0≦n g ≦K g , 1≦g≦G} and initial state N(0)=(0, . . . , 0). Since each FEG is independent and each FEG process corresponds to a Markovian queue, the joint steady-state probability distribution π(n) of the FEG process is given by the product-form represented by the following expression:
π( n )=Π g=1 G f g ( n g ),
in which f g (.) corresponds to the steady-state distribution of an M/M/R g /K g /K g type of queue.
According to a DPFS simulation, path unavailabilities, rather than path availability is used. The path unavailability U(i), 1≦i≦P, is the average proportion of time that path i is not operational in steady-state. Let T be the random variable of the recurrence time of the state n=0. It follows that the path unavailability U(i) is given by the following expression:
U ( i )= D ( i )(Σ g=1 G ξ g λ g )Π g=1 G f g (0)
in which D(i) is the average time that path i is not operational in a recurrence time T, ξ g =1, if FEG g is an infinite source, and ξ g if FEG g is a finite source. A method of estimating the average downtime D(i) in a recurrence time T is to apply regenerative simulation to the associated embedded discrete-time Markov chain (DTMC) with state n=0 as the regenerative state.
Let B circuit (k) be the state of the circuit bandwidths at time epoch k in the DTMC, and let P(k) be the state of the path routing at time epoch k in the DTMC. The state of the circuits and paths do not change during the holding time in a state. When there is a transition out of a state due to a FEG failure event or a repair, the state of the circuits becomes B circuit (k+1) and the state of the paths become P(k+1), in which P(k+1)=R(P(k), B circuit (k+1)) and R(.) is the path rerouting function, which is assumed to be given. Let U(i, k)=1 if path i is not operational at time epoch k in the DTMC under B circuit (k) and P(k), and 0 otherwise.
Let T(z) be the set of all possible tours t(z) of length z in the DTMC, starting at state 0 and returning back to state 0 in z steps, in which t(z)=(0, t 2 , . . . , t z , 0), t k is the DTMC state at time epoch k, t k =(t 1k , . . . , t Gk ), and t gk is the number of FEG g failures at time epoch k that have not been repaired. Let Π(t(z),z) be the probability of realizing tour t(z). Then, D(i) can be expressed as:
D ( i ) = ∑ z = 2 ∞ ∑ t ( z ) ∈ T ( z ) ∏ ( t ( z ) , z ) ∑ k = 1 z U ( i , k ) h ( t k ) ,
in which Π(t(z),z)=p(0, t 2 )p(t 2 , t 3 ) . . . p(t z , 0), and p(t a , t b ), t a , t b εF, is the state transition probability from state t a to t b in the DTMC. Hence, if the DTMC is simulated using conventional Markov Monte Carlo simulation starting at state 0 until it returns to state 0, then an estimate of D(i) is given by Σ k=1 z U(i,k)h(t k ), in which z is the realized number of steps in the tour in the DTMC. With the DTMC simulated using importance sampling, the state transition probabilities p(t a , t b ), t a , t b εF, are modified to the values p*(t a , t b ) so that FEG failure events are more likely to arrive. Then, D(i) can be expressed as:
D
(
i
)
=
∑
z
=
2
∞
∑
t
(
z
)
∈
T
(
z
)
∏
*
(
t
(
z
)
,
z
)
Λ
(
t
(
z
)
,
z
)
∑
k
=
1
z
U
(
i
,
k
)
h
(
t
k
)
,
in which Π*(t(z),z)=p*(0, t 2 )p*(t 2 , t 3 ) . . . p*(t z , 0), and
Λ ( t ( z ) , z ) = ∏ ( t ( z ) , z ) ∏ * ( t ( z ) , z ) = p ( 0 , t 2 ) p ( t 2 , t 3 ) … p ( t z , 0 ) p * ( 0 , t 2 ) p * ( t 2 , t 3 ) … p * ( t z , 0 )
is the likelihood ratio.
Hence, if a simulation of the DTMC starts at state 0 until it returns to state 0, then an estimate of the average downtime D(i) is given by Λ(t, z) Σ k=1 z U(i, k)h(t k ), in which z is the realized number of steps in the tour in the modified DTMC. The manner in which the DTMC transition probabilities can be modified to p*(.) is very general. In DPFS, the failure rates λ g are set in the FEG at an increased level until path failures are observed to occur or state n=0 is reached in a regenerative cycle. More specifically, in DPFS, the FEG failure bias is defined as a constant β,β>1, such that the failure rate λ g is increased to βλ g for 1≦g≦G. A target failure rate ratio α,α>0 is also defined. The target is a desired ratio of the sum of the biased FEG failure rates βλ g and the sum of the FEG repair rates μ g . If the target is α, whose value may be set by a user, then the FEG failure bias β is expressed by:
β=αΣ g=1 G μ g /Σ g=1 g λ g .
DPFS provides for a simulation of the DTMC with the biased failure rates βλ g starting from state n=0 until a path failure is observed or a state n=0 is reached. Once a path failure is observed, the bias β is set to 1.0 (i.e., turned off). The system then eventually returns to state n=0 after all FEG repairs have been made.
According to an exemplary embodiment, the DPFS algorithm for a mesh network with dynamic path restoration may be performed according to the following, in which the total number of independent regenerations is denoted by I, the estimate D(i) obtained in regeneration r is denoted by D′(i,r), and m=(m 1 , . . . , m G ) is a dummy variable.
Set the target failure rate ratio α.
Set the bias β.
For r = 1, ..., I
{
Set the initial state to n = 0.
Set m ≠ 0.
Initialize circuits state B circuit (0) and paths routing P(0).
For 1 ≦ g ≦ G: Set failure rate λ g to β λ g (i.e., turn the bias on).
For 1 ≦ i ≦ P: Set D′(i,r) = 0 and U(i, 0) = 0.
Set k = 0 and Λ = 1.0.
While m ≠ 0
{
For 1 ≦ i ≦ P: D′(i,r) = D′(i,r) + U(i, k)h(n).
If U(i, k) = 1 for any i, 1 ≦ i ≦ P:
Set failure rate of FEG g to λ g (i.e., turn the bias off) for
1 ≦ g ≦ G.
Randomly sample the next state transition out of state n in the
DTMC:
New state is m.
Set Λ = Λ p(n, m) / p*(n, m) and k = k+1.
Update B circuit (k).
Update path routing P(k) = R(P(k−1), B circuit (k)).
For 1 ≦ i ≦ P: Update U(i, k).
Set n = m.
}
For 1 ≦ i ≦ P: D′(i,r) = D′(i,r) Λ.
}
Following the completion of the DPFS simulation, the mean estimate of D(i), denoted by D′(i), can be expressed according to the following:
D′ ( i )=Σ r=1 I D′ ( i,r )/ I. (1)
Additionally, the estimate of the unavailability of path i, denoted by U′(i), can be expressed according to the following:
U′ ( i )= D′ ( i )(Σ g=1 G ξ g λ g )Π g=1 g f g (0). (2)
FIG. 2 is a diagram illustrating exemplary components of a device 200 that may correspond to one or more of the devices in environment 100 . For example, device 200 may correspond to node 110 and/or user device 120 depicted in FIG. 1 . As illustrated, device 200 may include a processing system 205 , memory/storage 210 including applications 215 , a communication interface 220 , an input 225 , and an output 230 . According to other implementations, device 200 may include fewer components, additional components, different components, and/or a different arrangement of components than those illustrated in FIG. 2 and described herein.
Processing system 205 may include one or multiple processors, microprocessors, data processors, co-processors, multi-core processors, application specific integrated circuits (ASICs), controllers, programmable logic devices, chipsets, field programmable gate arrays (FPGAs), system on chips (SoCs), microcontrollers, central processing units (CPUs), or some other component that may interpret and/or execute instructions and/or data. Depending on the type of processing system 205 , processing system 205 may be implemented as hardware, or a combination of hardware and software, may include a memory (e.g., memory/storage 210 ), etc.
Processing system 205 may control the overall operation, or a portion of operation(s) performed by device 200 . Processing system 205 may perform one or multiple operations based on an operating system and/or various applications (e.g., applications 215 ). Processing system 205 may access instructions from memory/storage 210 , from other components of device 200 , and/or from a source external to device 200 (e.g., another device, a network, etc.).
Memory/storage 210 may include one or multiple memories and/or one or multiple other types of tangible storage mediums. For example, memory/storage 210 may include one or multiple types of memories, such as, random access memory (RAM), dynamic random access memory (DRAM), cache, read only memory (ROM), a programmable read only memory (PROM), a static random access memory (SRAM), a single in-line memory module (SIMM), a dual in-line memory module (DIMM), a flash memory, and/or some other type of memory. Memory/storage 210 may include a hard disk (e.g., a magnetic disk, an optical disk, a magneto-optic disk, a solid state disk, etc.) and a corresponding drive. Memory/storage 210 may be external to and/or removable from device 200 , such as, for example, a Universal Serial Bus (USB) memory stick, a dongle, a hard disk, mass storage, off-line storage, or some other type of storing medium (e.g., a computer-readable medium, a compact disk (CD), a digital versatile disk (DVD), a Blu-Ray® disk (BD), etc.). Memory/storage 210 may store data, application(s), and/or instructions related to the operation of device 200 .
The term “computer-readable medium,” as used herein, is intended to be broadly interpreted to include, for example, a memory, a CD, a DVD, a BD, or another type of tangible storage medium.
Applications 215 may include software that performs various services or functions. For example, with reference to node 110 , applications 215 may include one or multiple applications pertaining to routing packets or other forms of network traffic. With reference to user device 120 , applications 215 may include applications for simulating a network in accordance with Stratified-DPFS, Adaptive Stratified-DPFS, PGFS, Stratified-PGFS, and/or Adaptive Stratified-PGFS.
Communication interface 220 may permit device 200 to communicate with other devices, networks, systems and/or the like. Communication interface 220 may include one or multiple wireless interface(s) and/or wired interface(s). Communication interface 220 may include one or multiple transmitter(s) and receiver(s), or transceiver(s).
Input 225 may permit an input into device 200 . For example, input 225 may include a keyboard, a mouse, a camera, a scanner, a microphone, a display (e.g., a touchscreen), a touchpad, a button, a switch, an input port, voice recognition logic, fingerprint recognition logic, a web cam, and/or some other type of visual, auditory, tactile, etc., input component. Output 230 may permit an output from device 200 . For example, output 230 may include a speaker, a display, a light, an output port, and/or some other type of visual, auditory, tactile, etc., output component.
Device 200 may perform operation(s) and/or process(es) in response to processing system 205 executing software instructions stored by memory/storage 210 . For example, the software instructions may be read into memory/storage 210 from another memory/storage 210 or from another device via communication interface 220 . The software instructions stored in memory/storage 210 may cause processing system 205 to perform processes described herein. Alternatively, according to another implementation, device 200 may perform processes based on the execution of hardware (e.g., processing system 205 , etc.), the execution of hardware and firmware, or the execution of hardware, software (e.g., applications 215 ), and firmware.
A problem that can arise when applying DPFS to a mesh network with dynamic path restoration is that DPFS may not obtain any non-zero estimates D′(i,r) for a path i. In such a case, DPFS is not able to obtain an estimate U′(i) for the unavailability of path i. This situation can arise if the unavailability of paths is imbalanced or have orders of magnitude difference. In practice, one reason for this problem stems from the fact that paths between node pairs that are geographically closer to each other will, naturally and typically, have a lower service unavailability compared to paths between node pairs that are more distant from each other. According to Stratified-DPFS, this potential problem may be minimized by turning the failure biasing off in DPFS only when the failure of each path, as opposed to any path, has been sampled. This makes it much more likely path failure samples for all paths in the network may be obtained.
In Stratified-DPFS, I(p) regenerations are assigned for the sampling of path p failures. The total number of simulated regenerations is I=I(1)+ . . . +I(P). Without loss of generality, I(1) may be set to I(1)=I(2)= . . . =I(P). According to exemplary embodiment, a Stratified-DPFS simulation may include to simulate I(1) regenerations with the failure biasing turned on until the failure of path 1 is sampled or the regenerative state n=0 is reached; simulate I(2) regenerations with the failure biasing turned on until the failure of path 2 is sampled or the regenerative state n=0 is reached; and so on, until all I regenerations have been completed. According to an exemplary embodiment, the Stratified-DPFS algorithm may be performed according to the following pseudo-code:
Set the target failure rate ratio α.
Set the bias β.
For 1 ≦ p ≦ P
{
For x = 1, ..., I(p)
{
r = x + Σ i=1 p−1 I(i)
Set the initial state to n = 0.
Set m ≠ 0.
Initialize circuits state B circuit (0) and paths routing P(0).
For 1 ≦ g ≦ G: Set failure rate λ g to β λ g (i.e., turn the bias on).
For 1 ≦ i ≦ P: Set D′(i,r) = 0 and U(i, 0) = 0.
Set k = 0 and Λ = 1.0.
While m ≠ 0
{
For 1 ≦ i ≦ P: D′(i,r) = D′(i,r) + U(i, k)h(n).
If U(p, k) = 1:
Set failure rate of FEG g to λ g (i.e., turn the bias off)
for 1 ≦ g ≦ G.
Randomly sample the next state transition out of state n in the
DTMC:
New state is m.
Set Λ = Λ p(n, m) / p*(n, m) and k = k+1.
Update B circuit (k).
Update path routing P(k) = R(P(k−1), B circuit (k)).
For 1 ≦ i ≦ P: Update U(i, k).
Set n = m.
}
For 1 ≦ i ≦ P: D′(i,r) = D′(i,r) Λ.
}
}
Following the completion of a Stratified-DPFS simulation, the estimates D′(i) and U′(i) can obtained using equations (1) and (2), respectively.
FIG. 3 is a flowchart of an exemplary process 300 for simulating a network model according to an exemplary embodiment of the Stratified-DPFS algorithm. Process 300 may be performed on user device 120 . For example, processing system 205 may execute a Stratified-DPFS application 215 that includes the Stratified-DPFS algorithm described.
In block 305 , user device 120 receives network information. For example, a user may input into user device 120 a network graph of a network (e.g., network 105 ) and initialization information (e.g., setting values to L, B link (x), B circuit (i), B p (i), (C, P, bias β, target failure rate ratio α, I regenerations, Λ, n, R g , repair rate μ g , failure rate λ g , etc.), as previously described. This information is stored in memory/storage 210 and accessible to the Stratified-DPFS application 215 during execution.
In block 310 , user device 120 simulates the network. For example, the network (e.g., network 105 ) is simulated (e.g., executed) by the Stratified-DPFS application 215 based on the network graph and initialization information. According to an exemplary embodiment, a DTMC is executed during the simulation with deterministic state holding times.
In block 315 , user device 120 biases failure probabilities and/or failure rates. For example, during the Stratified-DPFS simulation, the probability of transitioning from one state to another state is biased (e.g., increased or decreased), which may depend on the failure rates and/or repair rates. Additionally, during the Stratified-DPFS simulation, a particular number of regenerations I(p) is simulated until the failure of the path p is sampled or the regenerative state n=0 is reached. For example, as illustrated in block 320 , during the Stratified-DPFS simulation, it is determined whether the path failed. If a path failure does not occur during the Stratified-DPFS simulation (block 320 —NO), the simulation of the network and biasing of failure probabilities of the path continues (blocks 310 and 315 ). If a path failure does occur during the Stratified-DPFS simulation (block 320 —YES), the failure probabilities are unbiased (i.e., turned off) for this path (block 325 ).
In block 330 , user device 120 continues to simulate the network. For example the Stratified-DPFS simulation of the network continues with unbiased transition probabilities while the path is being repaired according to a repair rate. In block 335 , it is determined whether the network has returned to its original state. If the network has not returned to its original state (block 335 —NO), the Stratified-DPFS simulation of the network continues (block 330 ). If the network has returned to its original state (block 335 —YES), it is determined whether another regeneration for this path p is to be conducted (e.g., based on the value of I(p)) (block 340 ). If so (block 340 —YES), the Stratified-DPFS simulation continues to block 310 . If not (block 340 —NO), it is determined whether another path is to be simulated (block 345 ). For example, as previously described, during the Stratified-DPFS simulation, each path is sampled according to a particular number of regenerations I(p) so path failure samples may be obtained for all paths even when differences of unavailabilities among paths exist. If another path is to be simulated (block 345 -YES), process 300 continues to block 310 . Otherwise, the Stratified-DPFS simulation ends (block 350 ) and the estimates D′(i) and U′(i) can obtained using equations (1) and (2), respectively.
Although FIG. 3 illustrates an exemplary process 300 for simulating a network according to the Stratified-DPFS algorithm, according to other implementations, process 300 may include additional operations, fewer operations, and/or different operations than those illustrated in FIG. 3 and described herein.
According to Stratified-DPFS previously described, the number of regenerations I(p) assigned to the sampling of path p failures is a parameter. For example, I(1) can be set I(1)=I(2)= . . . =I(P). However, according to Adaptive Stratified-DPFS, the number of regenerations I(p) may be chosen to provide more regenerations to paths that have an intrinsically higher sample coefficient of variation of path unavailability relative to other paths. As a result, this may improve the estimates of path unavailability.
According to an exemplary embodiment of Adaptive Stratified-DPFS, the number of regenerations I(p) may be made proportional to the sample coefficient of variation of the downtime of path p in a regenerative cycle, as found with a set of T test regenerations. The test regenerations can be simulated using the Stratified-DPFS algorithm with I(p)=T/P, in which T is some multiple of P. Following the completion of the T test regenerations, the sample coefficient of variation χ′(i) of the downtime of a path i, 1≦i≦P, can be expressed according to the following expression:
χ
’
(
i
)
=
∑
r
=
1
T
(
D
′
(
i
,
r
)
-
D
′
(
i
)
)
2
D
′
(
i
)
2
(
T
-
1
)
.
Following the completion of the T test regenerations, a simulation according to Stratified-DPFS may be used, in which I=I(1)+ . . . +I(P) regenerations modifies the Stratified-DPFS based on the following expression:
I ( p )= I χ′( p )/Σ i=1 P χ′( i ).
Following the completion of the I regenerations, the estimates D′(i) are computed using all of the T+I regenerations that have been simulated, according to the following expression:
D ′( i )=Σ r=1 T+I D′ ( i,r )/( T+I ). (3)
The estimates for U′(i) are then calculated according to equation (2) stated above.
FIGS. 4A and 4B are flowcharts of an exemplary process 400 for simulating a network model according to an exemplary embodiment of the Adaptive Stratified-DPFS algorithm. Process 400 may be performed on user device 120 . For example, processing system 205 may execute an Adaptive Stratified-DPFS application 215 that includes the Adaptive Stratified-DPFS algorithm described.
In block 405 , user device 120 conducts with a set of T test regenerations. For example, as previously described, the test regenerations can be simulated using the Stratified-DPFS algorithm with I(p)=T/P, in which T is some multiple of P, and P is the number paths.
In block 410 , user device 120 calculates the sample coefficient of variation χ′(i) of the downtime of each path i, as explained above, based on the previously conducted T test regenerations.
In block 415 , user device 120 receives network information. For example, a user may input into user device 120 a network graph of a network (e.g., network 105 ) and initialization information (e.g., setting values to L, B link (x), B circuit (i), B path (i), C, P, bias β, target failure rate ratio α, I(p) regenerations for each path (calculated based on the sample coefficient of variation for each path i), Λ, n, m, G, R g , repair rate μ g , failure rate λ g , etc.), as previously described. This information is stored in memory/storage 210 and accessible to the Adaptive Stratified-DPFS application 215 during execution.
In block 420 , user device 120 simulates the network. For example, the network (e.g., network 105 ) is simulated (e.g., executed) by the Adaptive Stratified-DPFS application 215 based on the network graph and initialization information. According to an exemplary embodiment, a DTMC is executed during the simulation with deterministic state holding times.
In block 425 , user device 120 biases failure probabilities and/or failure rates. For example, as previously described above, during the Adaptive Stratified-DPFS simulation, the probability of transitioning from one state to another state is biased (e.g., increased or decreased), which may depend on the failure rates and/or repair rates. Additionally, as previously described, during the Adaptive Stratified-DPFS simulation, a particular number of regenerations I(p), based on the calculated sample coefficient of variation, is simulated for a path p until the failure of the path is sampled or the regenerative state n=0 is reached. For example, as illustrated in block 430 , during the Adaptive Stratified-DPFS simulation, it is determined whether the path failed. If a path failure does not occur during the Adaptive Stratified-DPFS simulation (block 430 —NO), the simulation of the network and biasing of failure probabilities of the path continues (blocks 420 and 425 ). If a path failure does occur during the Adaptive Stratified-DPFS simulation (block 430 —YES), the failure probabilities are unbiased (i.e., turned off) for this path (block 435 ).
In block 440 , user device 120 continues to simulate the network. For example the Adaptive Stratified-DPFS simulation of the network continues with unbiased transition probabilities while the path is being repaired according to a repair rate. In block 445 , it is determined whether the network has returned to its original state. If the network has not returned to its original state (block 445 —NO), the Adaptive Stratified-DPFS simulation of the network continues (block 440 ). If the network has returned to its original state (block 445 —YES), it is determined whether another regeneration for this path p is to be conducted (e.g., based on the value of I(p)) (block 450 ), as illustrated in FIG. 4B . If so (block 450 —YES), the Adaptive Stratified-DPFS simulation continues to block 420 . If not (block 450 —NO), it is determined whether another path is to be simulated (block 455 ). For example, as previously described, during the Adaptive Stratified-DPFS simulation, each path is sampled according to a particular number of regenerations I(p), based on the calculated sample coefficient of variation, so path failure samples may be obtained for all paths even when differences of unavailabilities between paths exist. If another path is to be simulated (block 455 —YES), the number of I(p) regeneration for the path is selected (block 460 ) and process 400 continues to block 420 . Otherwise, the Adaptive Stratified-DPFS simulation ends (block 465 ), and the estimates D′(i) are computed according to equation (3) in which all of the T+I regenerations have been simulated and the estimates for U′(i) are also calculated according to equation (2).
Although FIGS. 4A and 4B illustrate an exemplary process 400 for simulating a network according to the Adaptive Stratified-DPFS algorithm, according to other implementations, process 400 may include additional operations, fewer operations, and/or different operations than those illustrated in FIGS. 4A and 4B , and described herein.
According to an exemplary embodiment, another variation of DPFS called Path-Group Failure Importance Sampling (PGFS) is described. PGFS is applicable to mesh networks with S groups of static, pre-provisioned protection paths and a static path routing matrix P. In PGFS, a path group s is defined to be operational if at least one path in the group of N(s) paths is operational. Otherwise, the path group is not operational (i.e., if all paths in a path group are not operational). The notation for the downtime measures D( ) and unavailability measures U( ) now refers to groups of paths (i.e., path groups), as opposed to individual paths. Also, U(s, k)=1 if path group s is not operational at time epoch k in the DTMC under B circuit (k) and P, and 0 otherwise. The importance sampling scheme in PGFS turns off the failure biasing in a regenerative cycle only when all the N(s) paths in any particular path group s have failed or when state n=0 is reached. This is in contrast to DPFS in which the bias is turned off when any particular path fails, and in turn, the failure of a particular group could remain a rare event and may likely not be sampled in a simulation. The group failure biasing in PGFS makes the sampling of path group failures much more likely. According to an exemplary embodiment, the PGFS algorithm may be performed according to the following pseudo code:
Set P.
Set the target failure rate ratio α.
Set the bias β.
For r = 1, ..., I
{
Set the initial state to n = 0.
Set m ≠ 0.
Initialize circuits state B circuit (0).
For 1 ≦ g ≦ G: Set failure rate λ g to β λ g (i.e., turn bias on).
For 1 ≦ s ≦ S: Set D′(s,r) = 0 and U(s, 0) = 0.
Set k = 0 and Λ = 1.0.
While m ≠ 0
{
For 1 ≦ s ≦ S: D′(s,r) = D′(s,r) + U(s, k)h(n).
If U(s, k) = 1 for any s, 1 ≦ s ≦ S:
Set failure rate of FEG g to λ g (i.e., turn bias off)
for 1 ≦ g ≦ G.
Randomly sample the next state transition out of state n in the
DTMC:
New state is m.
Set Λ = Λ p(n, m) / p*(n, m) and k = k+1.
Update B circuit (k).
For 1 ≦ s ≦ S: Update U(s, k).
Set n = m.
}
For 1 ≦ s ≦ S: D′(s,r) = D′(s,r) Λ.
}
Following the completion of the PGFS simulation, the mean estimate of D(s) can be expressed by:
D′ ( s )=Σ r=1 I D′ ( s,r )/ I. (4)
The estimate of the unavailability of path group s can be expressed by:
U′ ( s )= D ′( s )(Σ g=1 G ξ g λ g )Π g=1 G f g (0). (5)
FIG. 5 is a flowchart of an exemplary process 500 for simulating a network model according to an exemplary embodiment of the PGFS algorithm. Process 500 may be performed on user device 120 . For example, processing system 205 may execute a PGFS application 215 that includes the PGFS algorithm described.
In block 505 , user device 120 receives network information. For example, a user may input into user device 120 a network graph of a network (e.g., network 105 ) and initialization information (e.g., setting values to L, B link (x), B circuit (i), B path (i), (C, P, bias β, target failure rate ratio α, Λ, n, R g , repair rate μ g , failure rate λ g , etc.), as previously described. Additionally, a user may input a value for S and define the path groups. A path group includes one or multiple paths. According to an exemplary implementation, the user may arbitrarily define path groups in the network. Alternatively, a path group may be defined based on a common source node, a common destination node, or a combination thereof. For example, a path group may be defined based on a particular destination from different sources, or a path group may be defined based on a particular source traversing different paths to a common destination. This information is stored in memory/storage 210 and accessible to the PGFS application 215 during execution.
In block 510 , user device 120 simulates the network. For example, the network (e.g., network 105 ) is simulated (e.g., executed) by the PGFS application 215 based on the network graph and initialization information. According to an exemplary embodiment, a DTMC is executed during the simulation with deterministic state holding times.
In block 515 , user device 120 biases failure probabilities and/or failure rates. For example, as previously described above, during the PGFS simulation, the probability of transitioning from one state to another state is biased (e.g., increased or decreased), which may depend on the failure rates and/or repair rates. As previously described, a path group failure occurs when all the paths in the path group fail. If a path group failure does not occur during the PGFS simulation (block 520 —NO), the simulation of the network and biasing of failure probabilities continues (blocks 510 and 515 ). If a path failure does occur during the PGFS simulation (block 520 —YES), the failure probabilities are unbiased (i.e., turned off) (block 525 ).
In block 530 , user device 120 continues to simulate the network. For example the PGFS simulation of the network continues with unbiased transition probabilities while the path group is being repaired according to a repair rate. In block 535 , it is determined whether the network has returned to its original state. If the network has not returned to its original state (block 535 —NO), the PGFS simulation of the network continues (block 530 ). If the network has returned to its original state (block 535 —YES), it is determined whether another simulation is to be conducted (block 540 ). For example, the user may enter the number of simulations to be run in block 505 , or the user may be prompted. However, during a PGFS simulation it is probable that the failure of each path group s will not be realized. Rather, a path group having a higher susceptibility of unavailability relative to other path groups will likely fail first. This issue is addressed in Stratified-PFGS and Adaptive Stratified-PGFS, described below. Referring back to FIG. 5 , if additional simulations are to be conducted (block 540 —YES), the PGFS simulation continues to block 510 . If no additional simulations are to be conducted (block 540 —NO), process 500 ends (block 545 ) and the estimates D′(s) and U′(s) can obtained using equations (4) and (5), respectively.
Although FIG. 5 illustrates an exemplary process 500 for simulating a network according to the PGFS algorithm, according to other implementations, process 500 may include additional operations, fewer operations, and/or different operations than those illustrated in FIG. 5 and described herein.
A problem that can arise when applying PGFS to a mesh network with groups of static protection paths is that PGFS may not obtain any non-zero estimates D′(s,r) for a path group s. In such a case, it is not able to obtain an estimate for U′(s). This situation can arise if the unavailability of path groups is imbalanced or have orders of magnitude difference. Imbalances may arise from differences in the distances between node pairs, from groups having different numbers of static paths, and from combinations of these factors. In practice, some path groups may include only one unprotected path, while other path groups may include two, three, or more paths, depending on the quality of service availability being offered to a customer. In Stratified-PGFS, this potential problem may be minimized by turning the failure biasing off in PGFS only when the failure of a particular path group, as opposed to any group, has been sampled. This makes it much more likely path group failure samples for all path groups in the network may be obtained.
In Stratified-PGFS, I(z) regenerations are assigned for the sampling of path group z failures. The total number of simulated regenerations is I=I(1)+ . . . +I(S). Without loss of generality, I(1) may be set to I(1)=I(2)= . . . =I(S). According to an exemplary embodiment, a Stratified-PGFS simulation may include to simulate I(1) regenerations with the failure biasing turned on until the failure of path group 1 is sampled or the regenerative state n=0 is reached, simulate I(2) regenerations with the failure biasing turned on until the failure of path group 2 is sampled or the regenerative state n=0 is reached; and so on, until all I regenerations have been completed. According to an exemplary implementation, the Stratified-PGFS algorithm may be performed according to the following pseudo code:
Set P.
Set the target failure rate ratio α.
Set the bias β.
For 1 ≦ z ≦ S
{
For x = 1, ..., I(z)
{
r = x + Σ i=1 z−1 I(i)
Set the initial state to n = 0.
Set m ≠ 0.
Initialize circuits state B circuit (0).
For 1 ≦ g ≦ G: Set failure rate λ g to β λ g (i.e., turn the bias on).
For 1 ≦ s ≦ S: Set D′(s,r) = 0 and U(s, 0) = 0.
Set k = 0 and Λ = 1.0.
While m ≠ 0
{
For 1 ≦ s ≦ P: D′(s,r) = D′(s,r) + U(s, k)h(n).
If U(z, k) = 1:
Set failure rate of FEG g to λ g (i.e., turn the bias off)
for 1 ≦ g ≦ G
Randomly sample the next state transition out of state n in the
DTMC:
New state is m.
Set Λ = Λ p(n, m) / p*(n, m) and k = k+1.
Update B circuit (k).
For 1 ≦ s≦ S: Update U(s, k).
Set n = m.
}
For 1 ≦ s ≦ S: D′(s,r) = D′(s,r) Λ.
}
}
Following the completion of the above simulation, the estimates D′(s) and U′(s) are obtained using equations (4) and (5), respectively.
FIG. 6 is a flowchart of an exemplary process 600 for simulating a network model according to an exemplary embodiment of the Stratified-PGFS algorithm. Process 600 may be performed on user device 120 . For example, processing system 205 may execute a Stratified-PGFS application 215 corresponding to the Stratified-PGFS algorithm described.
In block 605 , user device 120 receives network information. For example, a user may input into user device 120 a network graph of a network (e.g., network 105 ) and initialization information (e.g., setting values to L, B link (x), B circuit (i), B path (i), (C, P, bias β, target failure rate ratio α, I regenerations, Λ, n, R g , repair rate μ g , failure λ g , etc.), as previously described. Additionally, a user may input a value for S and define the path groups. A path group includes one or multiple paths. According to an exemplary implementation, the user may arbitrarily define path groups in the network. Alternatively, a path group may be defined based on a common source node, a common destination node, or a combination thereof. For example, a path group may be defined based on a particular destination from different sources, or a path group may be defined based on a particular source traversing different paths to a common destination. This information is stored in memory/storage 210 and accessible to the Stratified-PGFS application 215 during execution.
In block 610 , user device 120 simulates the network. For example, the network (e.g., network 105 ) is simulated (e.g., executed) by the PGFS application 215 based on the network graph and initialization information. According to an exemplary embodiment, a DTMC is executed during the simulation with deterministic state holding times.
In block 615 , user device 120 biases failure probabilities and/or failure rates. For example, as previously described above, during the Stratified-PGFS simulation, the probability of transitioning from one state to another state is biased (e.g., increased or decreased), which may depend on the failure rates and/or repair rates. Additionally, as previously described, during the Stratified-PGFS simulation, a particular number of regenerations I(z) is simulated for a path group s until the failure of the path group s is sampled or the regenerative state n=0 is reached. For example, as illustrated in block 620 , during the Stratified-PGFS simulation, it is determined whether the path group failed. If a path group failure does not occur during the Stratified-PGFS simulation (block 620 —NO), the simulation of the network and biasing of failure probabilities of the path group continues (blocks 610 and 615 ). If a path group failure does occur during the Stratified-PGFS simulation (block 620 —YES), the failure probabilities are unbiased (i.e., turned off) for this path group (block 625 ).
In block 630 , user device 120 continues to simulate the network. For example the Stratified-PGFS simulation of the network continues with unbiased transition probabilities while the path group is being repaired according to a repair rate. In block 635 , it is determined whether the network has returned to its original state. If the network has not returned to its original state (block 635 —NO), the Stratified-PGFS simulation of the network continues (block 630 ). If the network has returned to its original state (block 635 —YES), it is determined whether another regeneration for this path group s is to be conducted (e.g., based on the value of I(z)) (block 640 ). If so (block 640 —YES), the Stratified-PGFS simulation continues to block 610 . If not (block 640 —NO), it is determined whether another path group is to be simulated (block 645 ). For example, as previously described, during the Stratified-PGFS simulation, each path group is sampled according to a particular number of regenerations I(z) so path group failure samples may be obtained for all path groups even when differences of unavailabilities between path groups exist. If another path group is to be simulated (block 645 —YES), process 600 continues to block 610 . Otherwise, the Stratified-PGFS simulation ends (block 650 ) and the estimates D′(s) and U′(s) can obtained using equations (4) and (5), respectively.
Although FIG. 6 illustrates an exemplary process 600 for simulating a network according to the Stratified-PGFS algorithm, according to other implementations, process 600 may include additional operations, fewer operations, and/or different operations than those illustrated in FIG. 6 and described herein.
According to Stratified-PGFS previously described, the number of regenerations I(z) assigned to the sampling of path group z failures is a parameter and the number of regenerations is the same for each path group. However, according to Adaptive Stratified-PGFS, the number of regenerations I(z) may be chosen to provide more regenerations to path groups that have an intrinsically higher sample coefficient of variation of path group unavailability relative to other path groups. As a result, this may improve the estimates of path group unavailability.
According to an exemplary embodiment of Adaptive Stratified-PGFS, the number of regenerations may be made proportional to the sample coefficient of variation of the downtime of path group s in a regenerative cycle, as found with a set of T test regenerations. The test regenerations can be simulated using the Stratified-PGFS algorithm with I(s)=T/S, in which T is some multiple of S, and S is the number of path groups. Following the completion of the T test regenerations, the sample coefficient of variation χ′(s) of the downtime of path group s, can be expressed according to the following:
χ
’
(
s
)
=
∑
r
=
1
T
(
D
′
(
s
,
r
)
-
D
′
(
s
)
)
2
D
′
(
s
)
2
(
T
-
1
)
.
Following the completion of the T test regenerations, a simulation according to the Stratified-PGFS scheme may be used, in which I=I(1)+ . . . +I(S) regenerations modifies the Stratified-PGFS based on the following expression:
I
(
z
)
=
I
χ
’
(
z
)
∑
s
=
1
S
χ
’
(
s
)
.
Following the completion of the I regenerations, the estimates D′(s) are computed using all of the T+I regenerations that have been simulated, according to the following expression:
D ′( s )=Σ r=1 T+I D′ ( s,r )/( T+I ). (6)
The estimates for U′(i) are then calculated according to equation (5) stated above.
FIGS. 7A and 7B are flowcharts of an exemplary process 700 for simulating a network model according to an exemplary embodiment of the Adaptive Stratified-PGFS algorithm. Process 700 may be performed on user device 120 . For example, processing system 205 may execute an Adaptive Stratified-PGFS application 215 corresponding to the Adaptive Stratified-PGFS algorithm described.
In block 705 , user device 120 conducts a set of T test regenerations. For example, as previously described, the test regenerations can be simulated using the Stratified-PGFS algorithm with I(s)=T/S, in which T is some multiple of S, and S is the number of path groups.
In block 710 , user device 120 calculates the sample coefficient of variation χ′(z) of the downtime of each path group z, as explained above, based on the previously conducted T test regenerations.
In block 715 , user device 120 receives network information. For example, a user may input into user device 120 a network graph of a network (e.g., network 105 ) and initialization information (e.g., setting values to L, B link (x), B circuit (i), B path C, P, bias β, target failure rate ratio α, I(z) regenerations for each path group z (based on the sample coefficient of variation), Λ, n, m, G, R g , repair rate μ g , failure rate λ g etc.), as previously described. Additionally, a user may input a value for S and define the path groups. A path group includes one or multiple paths. According to an exemplary implementation, the user may arbitrarily define path groups in the network. Alternatively, a path group may be defined based on a common source node, a common destination node, or a combination thereof. For example, a path group may be defined based on a particular destination from different sources, or a path group may be defined based on a particular source traversing different paths to a common destination. This information is stored in memory/storage 210 and accessible to the Adaptive Stratified-PGFS application 215 during execution.
In block 720 , user device 120 simulates the network. For example, the network (e.g., network 105 ) is simulated (e.g., executed) by the Adaptive Stratified-PGFS application 215 based on the network graph and initialization information. According to an exemplary embodiment, a DTMC is executed during the simulation with deterministic state holding times.
In block 725 , user device 120 biases failure probabilities and/or failure rates. For example, as previously described above, during the Adaptive Stratified-PGFS simulation, the probability of transitioning from one state to another state is biased (e.g., increased or decreased), which may depend on the failure rates and/or repair rates. Additionally, as previously described, during the Adaptive Stratified-PGFS simulation, a particular number of regenerations I(z), based on the calculated sample coefficient of variation, is simulated for a path group s until the failure of the path group s is sampled or the regenerative state n=0 is reached. For example, as illustrated in block 730 , during the Adaptive Stratified-PGFS simulation, it is determined whether the path group failed. If a path group failure does not occur during the Adaptive Stratified-PGFS simulation (block 730 —NO), the simulation of the network and biasing of failure probabilities of the path group continues (blocks 720 and 725 ). If a path group failure does occur during the Adaptive Stratified-PGFS simulation (block 730 —YES), the failure probabilities are unbiased (i.e., turned off) for this path group (block 735 ).
In block 740 , user device 120 continues to simulate the network. For example the Adaptive Stratified-PGFS simulation of the network continues with unbiased transition probabilities while the path group is being repaired according to a repair rate. In block 745 , it is determined whether the network has returned to its original state. If the network has not returned to its original state (block 745 —NO), the Adaptive Stratified-PGFS simulation of the network continues (block 740 ). If the network has returned to its original state (block 745 —YES), it is determined whether another regeneration for this path group s is to be conducted (e.g., based on the value of I(z)) (block 750 ), as illustrated in FIG. 7B . If so (block 750 —YES), the Adaptive Stratified-PGFS simulation continues to block 720 . If not (block 750 —NO), it is determined whether another path group is to be simulated (block 755 ). For example, as previously described, during the Adaptive Stratified-PGFS simulation, each path group is sampled according to a particular number of regenerations I(z), based on the calculated sample coefficient of variation, so path group failure samples may be obtained for all path groups even when differences of unavailabilities between path groups exist. If another path group is to be simulated (block 755 —YES), the number of I(z) regeneration for the path group is selected (block 760 ) and process 700 continues to block 720 . Otherwise, the Adaptive Stratified-PGFS simulation ends (block 765 ), and the estimates D′(s) and estimates U′(s) are also calculated according to equations (6) and (5), respectively.
Although FIGS. 7A and 7B illustrate an exemplary process 700 for simulating a network according to the Adaptive Stratified-PGFS algorithm, according to other implementations, process 700 may include additional operations, fewer operations, and/or different operations than those illustrated in FIGS. 7A and 7B , and described herein.
The foregoing description of implementations provides illustration, but is not intended to be exhaustive or to limit the implementations to the precise form disclosed. Accordingly, modifications to the implementations described herein may be possible.
The algorithms described herein may be extended to the case of a mesh network that uses both dynamic path restoration and groups of static protection paths for the end-to-end protection of services. In such a mixed case, some end-to-end services may be protected by dynamic path restoration, some services may be protected using groups of static protection paths, and some services may not have any protection. The mixed case may arise in practice when different levels of service protection are to be provided to customers that have different service availability requirements and/or service level agreements. For the availability analysis of such a mixed network, Stratified-DPFS or Adaptive Stratified-DPFS may be applied to the services that are protected by dynamic path restoration and Stratified-PGFS or Adaptive Stratified-PGFS may be applied to the services that are protected by groups of static protection paths.
Other modifications may be applied to the algorithms described herein. For example, the rate of failure and/or the rate of repair may apply to circuits or some other type of network element. Also, embodiments described herein use failure rate λ g and repair rate μ g , but other types of transition rates (i.e., a rate to which a network element (e.g., a link, a node, etc.) and/or a model state (e.g., a Markov model state, etc.) transitions to a different state or condition), probabilities, etc. may be applied.
The terms “a,” “an,” and “the” are intended to be interpreted to include one or more items. Further, the phrase “based on” is intended to be interpreted as “based, at least in part, on,” unless explicitly stated otherwise. The term “and/or” is intended to be interpreted to include any and all combinations of one or more of the associated items.
In addition, while series of blocks are described with regard to the processes illustrated in FIGS. 3-7B , the order of the blocks may be modified in other implementations. Further, non-dependent blocks may be performed in parallel. Additionally, with respect to other processes described in this description, the order of operations may be different according to other implementations, and/or operations may be performed in parallel.
The embodiments described herein may be implemented in many different forms of software and/or firmware executed by hardware. For example, a process or a function may be implemented as “logic” or as a “component.” The logic or the component may include, for example, hardware (e.g., processing system 205 , etc.), a combination of hardware and software (e.g., applications 215 ), a combination of hardware and firmware, or a combination of hardware, software, and firmware. The implementation of software or firmware has been described without reference to the specific software code since software can be designed to implement the embodiments based on the description herein. Additionally, a computer-readable medium may store instructions, which when executed, may perform processes and/or functions pertaining to the exemplary embodiments described herein.
In the preceding specification, various embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional embodiments may be implemented, without departing from the broader scope of the invention as set forth in the claims that follow. The specification and drawings are accordingly to be regarded as illustrative rather than restrictive.
No element, act, operation, or instruction described in the present application should be construed as critical or essential to the embodiments described herein unless explicitly described as such. | A method including receiving a network model including paths having dynamic path restoration capabilities; receiving network simulation information including a failure rate that indicates a rate of failure, a repair rate that indicates a rate of repair, a number of repair personnel assigned to each failure equivalence group, and a regeneration value indicating a number of regenerations to occur for each designated path during a network simulation, biasing the failure rate; determining whether one of the designated paths enters a failure state; unbiasing the failure rate when it is determined that the designated path enters the failure state; identifying when the network model returns to an operative state; ceasing an execution of the network simulation when it is determined no other designated paths are to be simulated; calculating an average time of path unavailability for each designated path simulated; and calculating path unavailability for each designated path simulated. | 7 |
TECHNICAL FIELD
The present invention relates to a fluid control apparatus used in a semiconductor manufacturing apparatus or the like and a thermal sensor installation structure with respect to the fluid control apparatus and, specifically, a fluid control apparatus formed by integrating a plurality of fluid control instruments and a thermal sensor installation structure with respect to such a fluid control apparatus.
BACKGROUND ART
In a fluid control apparatus used in a semiconductor manufacturing apparatus, a plurality of fluid control instruments are arranged adjacently, and lines attached to a supporting member are arranged in parallel on a base member, so that integration which constitutes part of the fluid control apparatus is in progress without the intermediary of a pipe and a joint, and heating means may be provided thereon (PTL 1).
In the fluid control apparatus as described above, temperature control is required, and examples of sensors preferable therefor include a thermal sensor.
CITED REFERENCE
Patent Literature
PTL 1: JP-A-2006-349075
SUMMARY OF INVENTION
Technical Problem
According to the integrated fluid control apparatus, since a plurality of the fluid control instruments are arranged adjacently, a sufficient space for installing the thermal sensor is missing, and a problem of being difficult to install arises.
It is an object of the present invention to provide the fluid control apparatus which allows installation of the thermal sensor for temperature control by a simple work by an effective utilization of a space in the fluid control apparatus, and a thermal sensor installation structure with respect to the fluid control apparatus.
Solution to Problem
A fluid control apparatus of the invention is a fluid control apparatus including a first fluid control instrument and a second fluid control instrument adjacent to each other and a thermal sensor configured to measure a temperature of a fluid flowing in a fluid channel of the first fluid control instrument, further including a supporting member attached to one of the first fluid control instrument and the second fluid control instrument to support the thermal sensor.
The fluid control apparatus includes a plurality of lines arranged in parallel and formed normally by the first fluid control instrument and the second fluid control instrument arranged adjacently in series, and a plurality of third and fourth fluid control instruments and the like arranged in series thereto.
The thermal sensor is, for example, a sensor using a thermal electromotive force (Seebeck effect) generated by a temperature gradient between different types of metals. The thermal sensor may be installed in all of the lines of the fluid control apparatus and may be arranged some of the lines.
The supporting member configured to support the thermal sensor is attached to any one of the first fluid control instrument and the second fluid control instrument. In the case where the thermal sensor is attached to the first fluid control instrument, the supporting member may be attached by using the second fluid control instrument. However, in the case where attaching to the first fluid control instrument is easier, the supporting member may be attached by using the first fluid control instrument. Accordingly, installation of the thermal sensor is achieved by using the space in the fluid control instrument effectively and with a simple work.
The first fluid control instrument measured by the thermal sensor is, for example, a flow rate controller. However, it is not limited thereto, and may be the first fluid control instrument whereby an opening-and-closing valve, a regulator, a filter, and a channel block are measured by the thermal sensor as needed. The second fluid control instrument adjacent to the first fluid control instrument measured by the thermal sensor is, for example, the opening-and-closing valve. However, the flow rate controller, the regulator, the filter, the channel block, or the like is the second fluid control instrument adjacent to the first fluid control instrument as needed.
The first fluid control instrument is configured to control a flow rate (a mass flow controller or a fluid variable flow rate control apparatus), and the second fluid control instrument is preferably the opening-and-closing valve configured to block and release the fluid channel of the first fluid control instrument.
The second fluid control instrument (opening-and-closing valve) includes a casing having an opening-and-closing mechanism integrated therein, and the supporting member is preferably detachably attached to the casing from above the casing.
The fluid control instrument which controls the flow rate (that is, the mass flow controller, the fluid variable flow rate control apparatus, or the like) is a principle fluid control instrument arranged one per one line, and the opening-and-closing valve is always arranged adjacent thereto. Therefore, the temperature of a fluid flowing in the fluid control instrument which controls the flow rate is measured, and the supporting member of the thermal sensor is arranged by using the opening-and-closing valve, so that the structure of installation of the thermal sensor does not have to be change even when the number and the types of the fluid control instruments which constitute the single line vary.
Preferably, the first fluid control instrument (in other words, the mass flow controller, the fluid variable flow rate control apparatus, and the like) includes a leak port, and a detecting end portion of the thermal sensor is inserted into the leak port.
The leak port is used when testing the presence or absence of leakage, and by using this, the fluid temperature can be measured at a position close to the fluid without performing an additional work, and hence the fluid temperature can be measured accurately.
As long as the thermal sensor is capable of measuring the temperature by inserting the detecting end portion thereof into the leak port, various types may be used.
Preferably, the supporting member includes an annular main body provided with a slit at one position in a circumferential direction, and a pair of projecting portions provided integrally with the main body so as to extend the slits provided with the main body radially outward, and an inner peripheral surface of the main body has a shape corresponding to an outer periphery of a top wall of the casing.
In this configuration, attachment of the supporting member to the fluid control instrument is achieved easily.
Preferably, one of the projecting portions is provided with a screw insertion hole for allowing insertion of a male screw for the supporting member from an opposite surface to a surface opposing the other projecting portion, and the other projecting portion is provided with a female screw portion with which the male screw for the supporting member engages so as to extend in the same direction as the screw insertion hole.
In this configuration, by tightening the male screw for the supporting member, a width of the slit is narrowed and the supporting member is fixed to the fluid control instrument, so that the attachment of the supporting member with respect to the fluid control instrument is achieved easily.
The screw insertion hole and the female screw portion are provided so that the screw insertion hole is positioned upward by inclining with respect to an upper surface of the top wall of the casing, and the male screw for the supporting member is a hexagon socket head cap screw preferably.
In the integrated fluid control apparatus, since the plurality of lines are installed in parallel, it is difficult to secure a working space. However, by inclining the screw insertion hole (and the female screw portion in associated therewith), utilization of the space present above the top wall of the casing is enabled, so that the attachment of the supporting member is achieved so as to avoid interference with the casing, the supporting member or the like.
A thermal sensor installation structure with respect to the fluid control apparatus of the present invention is a thermal sensor installation structure for installing a thermal sensor configured to measure a temperature of a fluid flowing in a fluid channel of a flow rate controller on the fluid control apparatus including the flow rate controller configured to control the flow rate, and an opening-and-closing valve having a casing arranged adjacently to the flow rate controller and an opening-and-closing mechanism integrated therein, and configured to block and release the fluid channel of the flow rate controller, characterized in that a supporting member configured to support the thermal sensor is provided, and the supporting member is detachably attached to the casing of the opening-and-closing valve from above the casing.
The detecting end of the thermal sensor is preferably configured to allow insertion into the leak port provided on the flow rate controller.
Preferably, the supporting member includes an annular main body provided with a slit at one position in a circumferential direction, and a pair of projecting portions provided integrally with the main body so as to extend the slits provided with the main body radially outward, and an inner peripheral surface of the main body has a shape corresponding to an outer periphery of the top wall of the casing of the opening-and-closing valve.
Preferably, one of the projecting portions is provided with the screw insertion hole for allowing insertion of a male screw for the supporting member from an opposite surface to a surface opposing the other projecting portion, and the other projecting portion is provided with a female screw portion with which the male screw for the supporting member engages so as to extend in the same direction as the screw insertion hole.
The screw insertion hole and the female screw portion are provided so that the screw insertion hole is positioned upward by inclining and the male screw for the supporting member is a hexagon socket head cap screw preferably.
Advantageous Effects of Invention
According to the fluid control apparatus of the present invention, since the supporting member attached to any one of the first fluid control instrument and the second fluid control instrument and configured to support the thermal sensor is further provided, the thermal sensor is attached to the first fluid control instrument, and the supporting member configured to support the thermal sensor is required to be attached to only one of the fluid control instruments (the fluid control instrument which allows easier installation), so that installation of the thermal sensor is achieved by using the space in the fluid control apparatus effectively and with a simple work.
According to the thermal sensor installation structure with respect to the fluid control apparatus of the present invention, since the supporting member configured to support the thermal sensor is detachably attached to the casing of the opening-and-closing valve from above the casing, the installation of the thermal sensor is achieved by using the space in the fluid control apparatus effectively and with a simple work
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of an embodiment of a fluid control apparatus and a thermal sensor installation structure with respect to the fluid control apparatus of the invention.
FIG. 2 is a plan view of a principal portion of FIG. 1 .
FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2 .
FIG. 4 is an exploded perspective view of a thermal sensor unit.
REFERENCE SIGNS LIST
( 1 ) fluid control apparatus, ( 3 ) flow rate controller (first fluid control instrument), ( 4 ) opening-and-closing valve (second fluid control instrument), ( 12 a ) leak port, ( 15 ) casing, ( 15 a ) top wall ( 17 ) thermal sensor ( 17 a ) detecting end portion, ( 19 ) supporting member ( 21 ) main body ( 21 b ) inner peripheral surface ( 22 ) slit ( 23 ) first projecting portion ( 24 ) second projecting portion ( 25 ) male screw for the supporting member ( 26 ) screw insertion hole, ( 27 ) female screw portion
DESCRIPTION OF EMBODIMENTS
Embodiments of the invention will be described with reference to the drawings below. In the following description, expressions upper and lower correspond to upper and lower of FIG. 1 . The opening-and-closing valve side in FIG. 1 corresponds to front and a flow rate controller side corresponds to rear. The expressions upper, lower, front and rear are used for the sake of convenience, and the apparatus may be used with the upper and lower sides replaced by the left and right sides.
FIG. 1 illustrates part of two lines ( 2 ) of the integrated fluid control apparatus ( 1 ) including a plurality of lines.
The respective line ( 2 ) includes the flow rate controller (first fluid control instrument) ( 3 ), an opening-and-closing valve (second fluid control instrument) ( 4 ) configured to block and release a fluid channel of the flow rate controller ( 3 ) (not illustrated), a plurality of fluid control instruments (another opening-and-closing valve, regulator, filter and the like) which is not shown and a thermal sensor unit ( 5 ) configured to control the temperature of a fluid flowing in the fluid channel of the flow rate controller ( 3 ).
The flow rate controller ( 3 ) is referred to as a mass flow controller and includes a main body ( 11 ) having a function of adjusting the flow rate integrated therein and front and rear protruding channel blocks ( 12 ) ( 13 ) supporting the same. The protruding channel block ( 12 ) is provided with a leak port ( 12 a ) used in a leakage test for the flow rate controller ( 3 ) so as to open upward.
The opening-and-closing valve ( 4 ) is an air operate valve and includes a cubic block-shaped main body ( 14 ) having a channel communicating with the fluid channel of the flow rate controller ( 3 ), and a casing ( 15 ) provided upward of the main body ( 14 ) and having an actuator (opening and closing mechanism) integrated therein.
The casing ( 15 ) includes a top wall ( 15 a ) and a joint portion ( 16 ) configured to connect a compressed air introduction tube configured to introduce compressed air into the interior of the casing ( 15 ) at a center portion of the top wall ( 15 a ) is provided. The top wall ( 15 a ) has a shape like a disc having both sides cut off.
The fluid channel of the flow rate controller ( 3 ) and a fluid channel of the opening-and-closing valve ( 4 ) communicate with each other by a channel block ( 6 ) provided downward of the front protruding channel block ( 12 ) and the main body ( 14 ) of the opening-and-closing vale ( 4 ) so as to straddle the same. The front protruding channel block ( 12 ) and the main body ( 14 ) of the opening-and-closing valve ( 4 ) are fixed to the channel block ( 6 ) by a hexagon socket head cap screw ( 7 ) from above.
The thermal sensor unit ( 5 ) includes a thermal sensor ( 17 ) having a cord shape having a detecting end portion ( 17 a ) at a distal end thereof, a flange ( 18 ) passing through the thermal sensor ( 17 ) and a supporting member ( 19 ) attached to the opening-and-closing valve ( 4 ) and supporting the thermal sensor ( 17 ).
The thermal sensor ( 17 ) is provided with a sheath thermocouple.
The flange ( 18 ) has a square plate shape, and includes a sensor insertion hole ( 18 a ) configured to allow insertion of the thermal sensor ( 17 ), and a screw insertion hole ( 18 b ) configured to allow insertion of a flange male screw ( 20 ) for fixing the flange ( 18 ) with screwing.
The supporting member ( 19 ) includes an annular main body ( 21 ) provided with a slit ( 22 ) at one position in the circumferential direction, and a pair of projecting portions (first projecting portion ( 23 ) and a second projecting portion ( 24 )) provided integrally on the main body ( 21 ) so as to extend the slit ( 22 ) provided on the main body ( 21 ) radially outwardly.
The main body ( 21 ) has an outer peripheral surface ( 21 a ) having a short cylindrical surface, and an inner peripheral surface ( 21 b ) having a shape corresponding to the outer periphery of the top wall ( 15 a ) of the casing ( 15 ) (for example, both sides of the cylindrical surface are flat surfaces). The main body ( 21 ) is provided with the slit ( 22 ), so that resiliency in a direction of widening or narrowing the width of the slit ( 22 ).
The first projecting portion ( 23 ) is provided with a screw insertion hole ( 26 ) for allowing a male screw ( 25 ) for the supporting member to be inserted thereto from a surface on the opposite side to the surface opposing the second projecting portion ( 24 ) for the supporting member. The second projecting portion ( 24 ) is provided with a female screw portion ( 27 ) with which the male screw ( 25 ) for the supporting member is engaged so as to extend in the same direction as the screw insertion hole ( 26 ). The second projecting portion ( 24 ) is further provided with a female screw portion ( 28 ) extending upward.
The screw insertion hole ( 26 ) and the female screw portion ( 27 ) are orthogonal to a direction of extension of the slit ( 22 ) when viewed from above as illustrated clearly in FIG. 3 , but is inclined so that the insertion hole ( 26 ) comes upward with reference to the horizontal surface (a lower surface of the opening-and-closing valve ( 4 ), an upper surface of the top wall ( 15 a ) of the casing ( 15 ) and the like). The male screw ( 25 ) for the supporting member is a hexagon socket head cap screw, which can be tightened by using a tightening jig specific for the hexagon socket head cap screw.
The inner peripheral surface ( 21 b ) of the annular main body ( 21 ) of the supporting member ( 19 ) has a shape, which can be fitted loosely onto the outer peripheral surface of the top wall ( 15 a ) of the casing ( 15 ). Therefore, by tightening the male screw ( 25 ) for the supporting member, the width of the slit ( 22 ) is narrowed, whereby the supporting member ( 19 ) is fixed to the casing ( 15 ).
Surfaces of the pair of projecting portions ( 23 ) ( 24 ) opposing each other are provided with depressions ( 29 ) ( 30 ) respectively having a semi-circular cross-section extending in the vertical direction, and the thermal sensor ( 17 ) is inserted into a through-whole portion formed by these two depressions ( 29 ) ( 30 ). If the male screw ( 25 ) for the supporting member is tightened in order to fix the supporting member ( 19 ) to the casing ( 15 ), the depressions ( 29 ) ( 30 ) get closer to each other, and the thermal sensor ( 17 ) is clamped between the two depressions ( 29 ) ( 30 ).
The flange ( 18 ) having the thermal sensor ( 17 ) inserted into the sensor insertion hole ( 18 a ) is attached to the supporting member ( 19 ) by tightening the flange male screw ( 20 ) in a state in which the supporting member ( 19 ) is not attached on the opening-and-closing valve ( 4 ). The supporting member ( 19 ) to which the thermal sensor ( 17 ) is attached is fitted to the casing ( 15 ) from above and, in this state, the detecting end portion ( 17 a ) of the thermal sensor ( 17 ) is inserted into the leak port ( 12 a ), and then the supporting male screw ( 25 ) is tightened. When tightening the male screw ( 25 ) for the supporting member, since the insertion hole ( 26 ) and the female screw portion ( 27 ) are inclined, working from above the top wall ( 15 a ) of the casing ( 15 ) is enabled, so that the supporting member ( 19 ) may be attached while avoiding interference of the adjacent opening-and-closing valve ( 4 ) with respect to the top wall ( 15 a ) and the thermal sensor unit ( 5 ). In this manner, the thermal unit ( 5 ) is detachably attached to the opening-and-closing valve ( 4 ).
In order to measure the temperature of the fluid (gas), it is preferable to arrange the detecting end portion ( 17 a ) of the thermal sensor ( 17 ) at a position as close to the fluid as possible. By using the leak port ( 12 a ) provided on the protruding block ( 12 ) of the flow rate controller ( 3 ), the temperature may be measured with high degree of accuracy.
When using the leak port ( 12 a ), it is also possible to fix the flange ( 18 ) to which the thermal sensor ( 17 ) is inserted to the front protruding channel block ( 12 ) by using the hexagon socket head cap screw ( 7 ) fixed the front protruding channel block ( 12 ) to the channel block ( 6 ). In this case, however, it is also possible to remove the flow rate controller ( 3 ) at the time of attaching and detaching the thermal sensor ( 17 ) and hence the line is opened to the atmosphere and a problem that mounting and demounting of the thermal sensor ( 17 ) takes a lot of troubles arises.
In the above-described embodiment, it is not necessary to remove the flow rate controller ( 3 ), and attaching and detaching of the thermal sensor unit ( 5 ) can be performed without affecting the function of the fluid control apparatus ( 1 ). In addition, since the thermal sensor unit ( 5 ) is fixed by using the opening-and-closing valve ( 4 ), the space present in the fluid control apparatus ( 1 ) is effectively utilized, so that installation of the thermal sensor unit ( 5 ) is possible even when attaching of the thermal sensor ( 17 ) by the use of the hose band is difficult in terms of space.
In the description described above, the mas flow controller is exemplified as the flow rate controller ( 3 ). However, the fluid variable flow rate control apparatus may be made as the flow rate controller ( 3 ). Instead of installing the thermal sensor unit ( 5 ) by using the flow rate controller ( 3 ) and the opening-and-closing valve ( 4 ), other two fluid control instruments adjacent to each other may be used. In this case, an inner peripheral surface shape of the main body of the supporting member is changed as needed in accordance with the shape of the fluid control instrument to which the supporting member is attached. An outer peripheral surface shape of the main body of the supporting member may be a circumferential surface (cylindrical shape) as described above, and may be a square cylindrical shape.
INDUSTRIAL APPLICABILITY
According to the invention, since the thermal sensor may be installed easily to the fluid control apparatus used in the semiconductor manufacturing apparatus and the like, the control accuracy of the fluid control apparatus is improved and the application is expanded. | The present invention provides a fluid control apparatus which allows installation of a thermal sensor for temperature control by a simple work by an effective utilization of a space in the fluid control apparatus, and a thermal sensor installation structure with respect to the fluid control apparatus. The fluid control apparatus 1 includes a first fluid control instrument 3 and a second fluid control instrument 4 adjacent to each other and the thermal sensor 17 configured to measure a temperature of a fluid flowing in the first fluid control instrument 3 . The fluid control apparatus 1 further includes a supporting member 19 configured to support the thermal sensor 17 attached to the second fluid control instrument 4. | 5 |
RELATED APPLICATIONS
The present application is a continuation-in-part of U.S. patent application Ser. No. 09/894,461, filed Jun. 28, 2001, now abandoned, which claims priority to U.S. Provisional Application No. 60/214,998 filed Jun. 29, 2000. Each of the identified patent applications is hereby incorporated by reference in their entirety.
FIELD OF THE INVENTION
The present invention relates to the protection of materials stored on an industrial reel and, more particularly, to a corrugated wrap that is used to wrap the circumference of an industrial reel thereby providing protection to the materials stored thereon.
BACKGROUND OF THE INVENTION
Traditionally, wooden spools or industrial reels that are used to transport, store, and dispense various materials, e.g., fiber optics, other types of transmission cables, wires, etc., have had their contents protected through use of wood lagging strips, as shown in the prior art of FIG. 1 .
Referring to FIG. 1 , the traditional, prior art manner of preparing an industrial reel 10 for shipping through the use of wood lagging 12 is shown. Industrial reel 10 is generally fabricated from wood and includes a central spool 14 and a pair of end plates 16 . Various types of wire and/or cable 18 are wrapped about the central spool 14 and maintained thereon by virtue of end plates 16 allowing industrial reel 10 to operate as a shipment, storage and dispensement container all in one. To prepare industrial reel 10 for shipment, wood lags (lagging strips) 12 are placed one-by-one around the circumference of industrial reel 10 , requiring significant preparation time. Each wood lag 12 is secured at each end by a nail 19 to one of end plates 16 . The nail is directed into the width 20 of each of end plates 16 rather than the interior face 22 or exterior face 23 of end plates 16 . As such, a nail directed at an angle presents the possibility of extending through the interior face 22 of end plate 16 , resulting in an unreliable wood lag and the possibility of damaging the contents of industrial reel 10 .
Each of the lagging strips 12 has been cut to the width of the industrial reel and secured to end plates through the use of nails and a nail gun. The wood lagging 12 presents gaps between individual lagging strips through which foreign material may reach the industrial reel contents. The securing and subsequent removal of the lagging strips 12 from the industrial reel 10 adds significant time, and resultant costs, to the industrial reel shipping process. The use of nails and a powered nail gun provides the possibility of injury to the individual preparing the shipment and, as well, the possibility of injury to the spool contents through virtue of a misdirected, long-shanked nail. Additionally, the wood lagging 12 itself adds significant cost to the shipping due to the weight the lagging adds to the industrial reel and its contents. Further, the disposal and/or re-use of the wood lagging 12 is not easily facilitated and also presents a significant recycling concern. Similar problems are presented by plywood and Masonite® lagging when used in place of the wood lagging 12 .
In an effort to address at least some of the problems described above, one manufacturer has produced an alternative to wood lagging 12 . Specifically, the alternative is a triple-layered material, i.e., an inner layer of polypropylene foam cushioning, a middle layer of recycled polypropylene, and an outer layer of spunbonded polypropylene. The inner layer is placed in direct contact with contents of the industrial reel and is wrapped directly about the contents rather than about the circumference of the reel end plates, as shown in the prior art of FIG. 2 . The material is secured against the contents of the industrial reel through use of metal banding strips, leaving the end plates exposed.
Referring to FIG. 2 , the prior art alternative to the configuration of FIG. 1 is shown. In the prior art embodiment of FIG. 2 , a triple-layered material 24 , i.e., an inner layer of polypropylene foam cushioning, a middle layer of recycled polypropylene, and an outer layer of spunbonded polypropylene, is wrapped about the contents of industrial reel 10 and is positioned within the diameter of end plates 16 . Material 24 is held in position, i.e., in direct contact with the contents of industrial reel 10 , through use of one or more metal banding strips 26 . As a result of this direct contact, possible damage to the contents of industrial reel 10 is increased according to the pressure applied by metal banding strips 26 upon the contents. Note that because the contents of the industrial reel is most often spooled in a manner wherein the exterior of the contents is visible as a coursed configuration, i.e., the contents is in a side-to-side/top-to-bottom layer configuration as opposed to a layer-beneath-layer configuration as in adhesive tape, many portions of the contents are exposed for potential damage from the elements or reel-to-reel contact.
The alternative described above with reference to FIG. 2 does significantly reduce the time needed to wrap and unwrap the industrial reel, it does reduce the overall weight of the industrial reel, and it does eliminate the need for nails and the possible injury they may cause. However, it introduces new problems that were not present with wood lagging. Because the material 24 of the alternative approach is in direct contact with the contents of the industrial reel 10 , there is the possibility that the pattern of the material 24 will be imprinted on the contents of the industrial reel 10 . Further, because this alternative approach wraps the contents of the industrial reel 10 rather than the circumference of the end plates of the industrial reel 10 , there is a possibility that the exposed end plate 16 of an industrial reel 10 will roll into the contents of another industrial reel 10 , thereby damaging its contents.
As such, there is a need in the art for a product that addresses the problems presented by wood, plywood, and Masonite® lagging as well as the problems presented by the above-described alternative approach.
SUMMARY OF THE INVENTION
The needs described above are in large measure met by the industrial corrugated reel wrap of the present invention. The industrial reel wrap is designed for wrapping an industrial reel having a central spool and a pair of end plates connected thereto. The industrial reel contains spooled contents that are generally wound so that a plurality of courses exists between the first and second end plates. The industrial reel wrap includes a central portion that is spannable across a distance between the end plates of the industrial reel. The industrial reel wrap additionally includes first and second side portions that are coupled to the central portion. The first and second side portions each include a number of tabs along the length of the industrial reel wrap. The tabs are securable to the exterior surface of each the end plates.
In one embodiment of the invention the industrial reel wrap is preferably provided with sufficient length so that it may continuously surround the exterior circumference of the industrial reel, spanning the distance between end plates, and so that the last tab secured to the industrial reel overlaps the first tab secured to the industrial reel to ensure a complete enclosure thereof. The tabs may be place in a side-by-side or gapped arrangement.
In another embodiment of the invention, the central portion of the industrial reel wrap is unitary with the first and second side portions of the industrial reel wrap, with the side portions being separated from the central portion by a formed double crease. The double crease is preferably used when the industrial reel wrap is of a corrugated material and the flutes of corrugation are oriented opposite to the length of the reel wrap, i.e., the flutes extend from end plate to end plate rather than about the circumference of the industrial reel.
In still another embodiment of the invention, at least the central portion is provided with one or more scores enabling the industrial reel wrap itself to be folded to a more compact shape for shipment purposes. Bi-fold or tri-fold configurations are two options for a folding scheme of the industrial reel wrap. In the instance of the industrial reel wrap being made from a double-faced corrugated material, the score line is preferably only made through one face of the double-faced corrugated material leaving the underlying corrugated and second face intact.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a prior art configuration of an industrial reel, the contents of which have been protected through the use of wood lagging about the circumference of the industrial reel;
FIG. 2 is a prior art configuration of an industrial reel, the contents of which have been protected through the use of a wrap that is wrapped about and in direct contact with the contents of the industrial reel;
FIG. 3 depicts an industrial reel, the contents of which have been protected through the use of an industrial corrugated reel wrap of the present invention;
FIG. 4 depicts a corrugated material that may be used in the industrial corrugated reel wrap of the present invention;
FIG. 5 depicts an alternative corrugated material that may be used in the industrial corrugated reel wrap of the present invention;
FIG. 6 depicts one pattern, having closely spaced tabs, for the industrial corrugated reel wrap of the present invention;
FIG. 7 depicts an alternative pattern, having set-apart tabs, for the industrial corrugated reel wrap of the present invention;
FIG. 8 depicts the industrial corrugated reel wrap, with the pattern of FIG. 7 , wrapped partially about an industrial reel;
FIG. 9 depicts the industrial corrugated reel wrap of the present invention being applied to an industrial reel through use of a pneumatic fastening tool;
FIG. 10 depicts an industrial reel wrapped by the industrial corrugated reel wrap of the present invention wherein the end of the wrap is completed by topping the first tab with the last tab;
FIG. 11A depicts a single crease configuration that may be provided between the center and side portions of the industrial reel wrap;
FIG. 11B depicts a double crease configuration that may be provided between the center and side portions of the industrial reel wrap;
FIG. 12 depicts the industrial corrugated reel wrap having been scored to enable folding for shipping purposes; and
FIG. 13 depicts a plurality of industrial corrugated reel wraps that have been folded and stacked atop each other for shipping.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An industrial, corrugated reel wrap of the present invention is shown generally at 50 in the figures and is used to protect and shield the contents of an industrial reel 10 . The corrugated reel wrap 50 provides for fast installation and removal, significantly reduces the amount of weight added to the industrial reel compared to wood lagging, and reduces the possibility of injury to the shipper and/or contents of the industrial reel.
The industrial, corrugated reel wrap 50 of the present invention is shown in FIGS. 3–5 . As FIG. 3 depicts, industrial, corrugated reel wrap 50 is designed to span the overall width of industrial reel 10 and to be secured to the exterior of industrial reel 10 by staples 51 , thereby avoiding the problems associated with nailing wood lagging to the end plates. Staples 51 are selected with a length that is insufficient to penetrate the end plate 16 , thereby protecting the contents of the industrial reel 10 from damage. Referring to FIGS. 3 and 6 , industrial, corrugated reel wrap 50 incorporates a central portion 56 , which is of sufficient width to extend between end plates 16 of industrial reel 10 , and two side portions 58 that are preferably unitary with central portion 56 , being joined at a respective side margin of the central portion 56 . Each of side portions 58 includes a plurality of tabs 60 that have been preferably die-cut to include angled sides 62 that extend into an arc portion 64 that is common with the angled side 62 of the next proximate tab 60 . Industrial, corrugated reel wrap 50 may be of any desired length and width that is suitable to a specific application.
As FIG. 4 depicts, industrial, corrugated reel wrap 50 is not a wood product but rather is a multi-layered material manufactured from high-density polyethylene (HDPE), i.e., a plastic, having a basis weight of 300 to 500 lbs. Of course, other plastics or plasticized materials, e.g., plastic coated fiberboard, may be used without departing from the spirit or scope of the invention. HDPE is used to create an industrial, corrugated reel wrap 50 that preferably incorporates two outside liners 52 and a fluted center 54 , as shown in FIG. 4 . Alternatively, industrial, corrugated reel wrap 50 may include only a single outside liner 52 in combination with fluted center 54 , as shown in FIG. 5 . The flutes 55 of fluted center 54 may extend along the length or along the width of industrial, corrugated reel wrap 50 . Industrial, corrugated reel wrap 50 may be manufactured through lamination, extrusion, or other like processes.
Because industrial, corrugated reel wrap 50 is manufactured from HDPE it is 100% recyclable, thus eliminating the element of waste product that results from wood lagging. Further, because industrial, corrugated reel wrap 50 is manufactured from HDPE, it may be customized with minimal investment and can be made available in a wide range of colors, including translucents. The HDPE material also means that industrial, corrugated reel wrap 50 is unaffected by water, is stronger and more durable than corrugated fiberboard, is extremely lightweight, will not rust, rot, mildew or corrode like metal or wood, and will resist a wide range of chemicals, grease and dirt. The HDPE material allows industrial, corrugated reel wrap 50 to be easily and clearly printed upon, and to be tear, puncture, and impact-resistant for protection of the contents of industrial reel 10 . The HDPE material also allows for industrial, corrugated reel wrap 50 to be made anti-static, non-conductive, ultra-violet inhibiting, flame retardant, corrosion retardant, and/or non-skid if desired. Additionally, industrial, corrugated reel wrap 50 may be made with FDA approved resins.
FIGS. 7 and 8 depict industrial, corrugated reel wrap 50 incorporating an alternative tab pattern to that presented in FIGS. 3 and 6 ; of course, numerous other patterns may be used for corrugated reel wrap 50 without departing from the spirit or scope of the invention. The alternative pattern finds industrial, corrugated reel wrap 50 having a central portion 56 , which is of sufficient width to extend between end plates 16 of reel 10 , and two side portions 58 that are preferably unitary with central portion 56 . Each of side portions 58 includes a plurality of tabs 60 that have been preferably die-cut to include angled sides 62 . However, different from the pattern described in the paragraph above, tabs 60 are separated by an elongate space 63 , i.e., gapped, that is substantially equivalent in width to that of one of tabs 60 .
FIG. 9 depicts the application of industrial, corrugated reel wrap 50 to an industrial reel 10 . As shown, industrial, corrugated reel wrap 50 is positioned such that central portion 56 extends between end plates 16 of reel 10 , allowing tabs 60 to protrude outward. To secure tabs 60 to industrial reel 10 , they are manually bent downward and fastened, preferably through use of a pneumatic fastening tool 66 (e.g., stapler, nail gun, etc.) to exterior face 23 of end plate 16 , causing central portion 56 to smoothly lie along the edges of end plates 16 . Arc portion 64 and spacing between tabs 60 allow each tab 60 to be bent individually without stress on proximate tabs 60 and to lie flat against end plate 16 without causing gaps between end plates 16 and central portion 56 . Only one fastener 68 (including, for example, staple 51 ) is needed per tab 60 to secure it to industrial reel 10 . Fasteners 68 are selected to have a shank length such that each of fasteners 68 does not penetrate end plate 16 and protrude through interior face 22 upon being secured to end plate 16 . The process of bending and fastening is repeated for each tab 60 through the rolling of industrial reel 10 until all tabs 60 are secured and the area intermediate end plates 16 of industrial reel 10 is enclosed.
Completing the enclosure of the area intermediate end plates 16 may be achieved by overlapping the ends of industrial, corrugated reel wrap 50 . Using this manner of completing the enclosure allows for industrial, corrugated reel wrap 50 to be dispensed and cut to a desired length for application to industrial reel 10 . In a preferred embodiment of the invention, the industrial, corrugated reel wrap 50 is manufactured such that an overlap in the ends of the wrap 50 also results in an overlap of tabs 60 , i.e., at least a portion of the very last tab 60 a on industrial, corrugated reel wrap 50 is secured atop the very first tab 60 b of industrial, corrugated reel wrap 50 , see FIG. 10 . The overlap of first 60 b and last 60 a tabs 60 helps to ensure that industrial, corrugated reel wrap 50 does not separate keeping the contents of the industrial reel 10 always enclosed. In addition to or alternatively, industrial, corrugated reel wrap 50 may be manufactured to a specific length where the ends overlap to complete the enclosure. Within these alternatives, if desired, the ends of industrial, corrugated reel wrap 50 may be provided with an interlocking notch 70 and tab 72 combination to complete the enclosure of wrap 50 , as shown in FIGS. 3 and 9 .
In a preferred embodiment of industrial, corrugated reel wrap 50 , side portions 58 are unitarily joined to central portion 56 via a single seam crease 72 , see FIG. 11A and, even more preferably, through a double seam crease 74 , see FIG. 11B . The single seam crease 72 is more appropriately used when the direction of corrugation of the flutes 55 of the industrial reel wrap 50 extend through the length of the industrial reel wrap 50 ; the direction of corrugation is in the same direction as the seam crease 72 making the bending or folding of the tabs 60 at the crease an easy task. The double seam crease 74 is more appropriately used when the direction of corrugation of the flutes 55 of industrial reel wrap 50 extend cross-wise to the length of the industrial reel wrap 50 . In this instance, the corrugation of the flutes 55 works against the easy folding of the tabs 60 and the double seem crease 74 provides two flex points 76 at the seam enabling easier folding of the tabs 60 .
By using industrial, corrugated reel wrap 50 as described above, the time spent by an individual in preparing an industrial reel for shipment is reduced by greater than ⅓ when compared to traditional wood lagging. The time for removing industrial, corrugated reel wrap 50 is also significantly reduced over the removal time of wood lagging. Further, industrial, corrugated reel wrap 50 is of a greatly reduced weight, compared to wood, plywood, or Masonite® lagging, for reduced shipping costs. Further, the possibility of injury to the shipper or to the industrial reel contents is reduced by using fasteners of reduced length and preferred placement on end plate 16 . For example, staple prongs are of a significantly reduced length and width when compared to that of the shank of a nail which is used with wood lagging. Additionally, the shank of a nail used in fastening the present invention may be shorter than that used in wood lagging since the present invention is secured to exterior face 23 of end plate 16 rather than fully penetrating a piece of wood lagging and then being directed into the width of end plate 16 as is the case in wood lagging.
Further, by using industrial, corrugated reel wrap 50 as described above, only the circumference of an industrial reel 10 is wrapped, i.e., there is no direct contact with the contents of the industrial reel 10 when the contents assume a circumference that is less than the circumference of the end plates 16 . There is no possibility that the pattern of the industrial, corrugated reel wrap 50 is imprinted on the contents in this condition. When wrapping the circumference of the end plates 16 with industrial, corrugated reel wrap 50 , a substantially rigid material, the possibility that an object may break through wrap 50 to damage the contents of the industrial reel 10 is virtually eliminated unlike the alternative prior art method shown in FIG. 2 . Wrapping of the circumference with industrial, corrugated reel wrap 50 also provides a moisture barrier for the underlying contents of industrial reel 10 .
For shipping to customer locations wherein the industrial, corrugated reel wraps 50 will be applied to industrial reels 10 , the industrial reel wrap 50 is preferably provided with one or more scores 78 , FIG. 12 shows a preferred embodiment incorporating two, across the width of the industrial reel wrap 50 . The scores 78 preferably only penetrate one of the outside liners 52 ; the scores 78 do not continue down through the fluted center 54 or the second of the outside liners 52 . The scoring of the industrial reel wrap 50 enables the industrial reel wrap 50 to be folded, stacked atop each other, and atop a pallet for shipping. FIG. 13 shows a stack of tri-folded industrial reel wraps 50 , each of the reel wraps 50 has two scores 78 along its width. The cutting of only one of the outside liners 52 of the industrial reel wrap 50 , leaving the fluted center 54 and remaining outside liner 52 intact prevents the industrial reel wrap 50 from separating or splitting to ensure continuous and complete enclosure of the contents of the industrial reel 10 .
The present invention may be embodied in other specific forms without departing from the spirit of the essential attributes thereof; therefore, the illustrated embodiments should be considered in all respects as illustrative and not restrictive, reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention. | An industrial reel wrap is designed for wrapping an industrial reel having a central spool and a pair of end plates connected thereto. The reel wrap includes a central portion that is spannable across a distance between the end plates of the reel. The reel wrap additionally includes first and second side portions that are coupled to the central portion. The first and second side portions each include a number of tabs along the length of the reel wrap. The tabs are securable to the exterior surface of each the end plates, the first and last of the tabs are preferably overlapped to completely enclose the industrial reel. The tabs are separated from the central portion by a double crease seam to enable easier folding of the tabs. The reel wrap may be scored to enable compact folding for shipment. | 1 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a divisional of application Ser. No. 09/800,148, filed Mar. 6, 2001.
FIELD OF THE INVENTION
This invention relates to electrical contacts between printed circuit boards and electronic modules, particularly involving contact sites through land grid array (LGA) sockets.
BACKGROUND OF THE INVENTION
A typical LGA interposer system comprises a printed circuit board (PCB) with electrically conductive contact pads, a module (or other printed circuit board) with a corresponding set of electrically conductive contact sites, an interposer between the module and the printed circuit board and an array of spring elements to make electrical contact between the module and the printed circuit board. Clamps are used to mechanically hold the module to the interposer and to electrically join the module contact sites through the spring elements to the printed circuit board pads.
A cooling device or heat sink is typically coupled to the module required to provide cooling of the entire electronic assembly. Many of the heat sinks have a substantial size and mass relative to the other components. This size and mass create a moment arm, causing relative movement between the module and the other components when the assembly is subjected to shock or vibration.
The spring elements used to make the electrical contact between the module sites and the PCB pads may be any one of a number of different types. Among the spring elements are metal filled elastomers, such as those sold by Tyco Inc. (formerly Thomas & Betts) as Metal Particle Interconnect Elastomers. Others are compressible wadded wires, commonly referred to as fuzz buttons shown, for example, in the following patents: U.S. Pat. No. 5,552,752; U.S. Pat. No. 5,146,453 and U.S. Pat. No. 5,631,446. These are small, irregularly wound and inter-twined pads or balls and are made of gold plated beryllium copper wool or gold plated molybdenum wire. Metal springs are also used. These metal springs generally are leaf springs having a number of geometries, such as C-shaped or V-shaped.
In typical LGA applications, shock and vibration can cause a variety of problems which may manifest themselves in decreased reliability and life expectancy, resulting in ongoing maintenance and repair problems. These problems can be viewed from two coordinate systems; 1) The in-plane or x-y axis, as seen when looking at an LGA interposer site, and 2) The x-z or y-z planes which are perpendicular to the board surface.
Problems along the In-plane or x-y Axis
Typically, an interposer structure uses eight leaf springs (two per side positioned toward the corners) to center the module in an interposer housing. Using spring support on all four edges of the module provides very low (i.e. near zero) spring constant for the module during shock and vibration. As the heat sink mass increases, the natural frequency of the response decreases.
Sliding can occur between the surface of the module and the corresponding surface of the interposer. The module is held in position relative to the interposer by at least two springs on each edge of the module. The shear force between the surfaces is equal to the clamping force applied at right angles to the surfaces, multiplied by the coefficient of friction between the two surfaces.
Efforts that have been used to combat this problem include increasing the assembly clamping force. This increases the friction between the module and the interposer and tends to flatten the two components. Consequently, it increases stresses within these components, thereby leading to cracks or failures of the module and reduced product life
As the response natural frequency of the system decreases, the alignment springs provide less module restraint during excitation. The only remaining support is the frictional contact that may occur between the module and the spring elements and/or interposer housing.
Problems along the x-z or y-z Plane
The z-axis problem contains some additional attributes of significance. Module substrate flatness is a critical factor for module motion that is perpendicular to the printed circuit board surface. A flatness of 3 to 6 mils for a ceramic module is common in the industry today, but there is no control over whether the surface is ‘concave’ or ‘convex’. For a ‘convex’ module surface, the center portion of the contact array field is closer to the interposer surface than to the edge portions. There are no established standards or specifications for the flatness of the surface of the interposer, although it is common to strive for a flatness of +/−2 mils.
When a non-flat module substrate is mated to an interposer, this center of the substrate can contact the interposer housing surface first, creating a second loading path (parallel to the spring elements). If there are approximately the same number of spring elements on either side of the contacting portions of the module and interposer, the net stiffness of the elements is again very small. When this assembly is subject to shock and vibration, the heat sink mass and movement arm tend to ‘rock’ the module in the interposer housing. This ‘rocking’ creates contact micro-motion, leading to contact wear, and electrical resistance problems. Contact motion of a small amplitude or micro-motion creates two reliability risks for an electrical contact. First is the risk of disturbing the contact ‘a’ or asperity spot where electrical contact actually occurs. If the ‘a’ spot is disturbed, the electrical contact must be re-established before the next pulse of a digital signal can pass through the connection. This time to re-establish would be measured in nano-seconds. Secondly, small amounts of contact motion can wear the plated precious metal layer intended to protect the contact from corrosion. If the plated layer wears through to the base material susceptible to corrosion, the electrical resistance of the contact can increase, thereby inhibiting the electrical signal from passing.
Another drawback is that there is no protocol for the assembly of the module and interposer in a manner that will provide for the two mating surfaces to be matched so that a concave portion of one body will coincide with a convex surface of the other. Thus, whenever there are non-planar contact points, micro movements in the plane or at an angle to the plane of the module and the interposer can occur.
U.S. Pat. No. 5,720,630 relates to electrical connectors that are adapted to function reliably even under conditions of extreme vibration. These serve to overcome the necessity of providing a large contact area between male and female contact sites. This decreases the degree of design flexibility for the connectors, and the weight of the connector assembly. The connectors utilize a compressible, conductive contact enabling electric signals and current to flow between male contact pins.
SUMMARY OF THE INVENTION
The present invention relates to the prevention or reduction of the contact motion during shock and vibration or other mechanical disturbance of an LGA socket, thereby substantially minimizing electrical resistance problems and mechanical failures between a printed circuit board and a module or other PCB.
One objective of the present invention is to increase the natural frequency of the module-to-LGA mounting system under a given load to accommodate more mechanical disturbance of the assembled system. As the natural frequency increases, the displacement decreases, thereby providing less module motion and increased contact life.
Another objective is to alleviate contact micro-motion and to reduce reliability problems, while at the same time supporting larger heat sink masses.
Yet another objective is to reduce rocking motion between a module, such as a ceramic module, and an interposer in situations wherein the contact surface of the module is convex with respect to the surface of the interposer.
For purposes of briefly describing the present invention, the interposer, module and circuit board are deemed to be rectangular in shape, generally flat and relatively thin in proportion to their planar surfaces. It is understood, however, that the teachings of the invention are likewise applicable to these components, even though they may have other designs, shapes, and configurations.
One solution to this motion problem in the x-y plane is to provide fixed restraints around the periphery on at least two edges of the module/interposer system. One arrangement comprises the use of two substantially rigid projections on a first edge of the interposer. At least one, and more typically two, spring members are located on an edge (i.e. edge 3 ) opposite of the first edge. One or two substantially rigid projections are positioned on a second edge (edge 2 ) that is adjacent and substantially perpendicular to the first edge to provide a second restraint. At least one, and more typically at least two, spring members are located on the edge (edge 4 ) opposite of the second edge, thereby creating a force toward the alignment position on the second edge.
Among the benefits of this solution along the x-y plane are:
Alignment spring rate does not essentially cancel during micro-motion;
Better absolute positional tolerance; and
During shock and vibration toward the spring members (i.e. edges 3 and 4 ), spring preload must be overcome before module motion is a concern.
Rocking motion along the z-axis may be caused by any convex curvature of the surface of the module facing the interposer, or partial compression of contacts leaving a gap between the adjacent surfaces of the module and the interposer insulator. This problem is solved by the use of one or more substantially rigid supports, which are provided on the interposer along the z-axis. These supports serve as stops to prevent rocking of the module relative to the interposer during shock and vibration. The force to maintain contact between the stops and the module is provided by the conventional clamping system. These rigid supports provide a support rim on the perimeter of the module that is higher than the non-flatness of the module. Preferably, the combined height of the stops is at least equal to two times the vertical distance between the perimeter of the convex surface and the top of the convex surface, whereby the stops engage the perimeter of the module without the module contacting the planar portion of the interposer.
Advantages of the z-axis solution:
A common goal for the LGA interposer system is to increase the contact compliance or contact travel under a given amount of loading to accommodate more actuation tolerance. As the contact compliance increases, the spring rate decreases, thereby allowing for greater module motion during actuation and, therefore, during shock and vibration. This z-axis support method alleviates contact micro-motion and reliability problems while supporting larger heat sink masses.
The present invention comprises an electronic assembly including a printed circuit board, an electronic module and an interposer, and a method of controlling the relative motion between the module and the interposer in such an assembly. The printed circuit board includes a plurality of electrical contact pads thereon. The module can be made of ceramic, a dielectric, plastic or other rigid material. It has a bottom surface that includes a plurality of contact sites, some of which correspond to the pads on said printed circuit board. The interposer is positioned between said printed circuit board and said bottom surface of the module and comprises an insulator and a plurality of compressible spring elements, each adapted to electrically connect one of said electrical contact pads of said printed circuit board to a respective one of said contact sites on the surface of said module. The assembly further includes means for controlling relative motion between the interposer and the module. This is achieved by the use of an interposer having two spacedly positioned supports projecting therefrom toward said module such that said module engages said supports. If the module is not planar, but has a convex surface facing the interposer, the supports serve as stop members spaced apart and extending at right angles to the planar surface of the interposer, and along two edges thereof, into contact with the module. These stops serve to limit rocking motion caused by the convex curvature of the module relative to the planar surface of the interposer. The interposer may also include two contiguous edges containing edge restraints positioned to align the contact sites of the module with the contact pads on the PCB. Springs interconnect the other two edges of the interposer to the module. The restraints serve to limit sliding along the planar surfaces of the module and the interposer.
The invention also relates to an interconnection between one or more contact pads on a surface of a printed circuit board and the corresponding contact sites on a surface of an electrical module. The interposer is positioned between the printed circuit board and the module and includes a compressible, electrically conductive contact for each pad and site. The interposer further includes a plurality of stop members and/or restraints projecting therefrom to limit the motion between the module, the interposer and the printed circuit board caused by the clamping force applied during the assembly process. If the bottom surface of the module is convex, the interposer includes two spacedly positioned stop members projecting therefrom toward said module such that the edges of the module engage only said stop members and the spring elements. The two stop members extend at right angles to the planar surface of the interposer and limit the rocking movement of the module that may occur due to shock and vibration. Means for controlling the relative sliding motion between the module and the interposer comprise two contiguous edges of the interposer containing edge restraints positioned to align the contact sites of the module with the contact pads of the PCB. This also serves to reduce the available surface area of the interposer against which the module can slide. The springs interconnect the other two edges of the interposer to the module.
The invention also relates to a sub-assembly and its method of assembly comprising a rigid electronic module having a generally planar surface and an interposer having a generally planar surface against which the module is clamped. The module can be ceramic, a dielectric, plastic or other rigid material. Means are provided to limit the relative movement of the module with respect to the interposer when the sub-assembly is subject to shock and/or vibration. The limiting means serves to limit relative sliding movement along the x and y axis parallel to the planar surfaces, and comprises restraints along two contiguous sides of the interposer. The limiting means can also limit the relative movement along the z-axis orthogonal to the planar surfaces and comprise at least two stops that restrict the rocking movement of the module with respect to the interposer caused by a lack of planarity of the bottom surface of the module.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view of a printed circuit board assembly;
FIG. 2 is a cross-sectional view of a module of the prior art;
FIG. 3 is a view in cross-section of the module showing partial details of the present invention for limiting motion in the x-z and y-z directions;
FIG. 4 is an enlarged sectional view taken along lines 4 - 4 ′ of FIG. 3;
FIG. 5 is a planar view of the prior art showing a module suspended from an interposer housing;
FIG. 6 is a cross-sectional view taken along lines 6 - 6 ′ of FIG. 5;
FIG. 7 is a planar view of a module of the present invention suspended from an interposer housing;
FIG. 8 is a cross-sectional view taken along lines 8 - 8 ′ of FIG. 7, and
FIG. 9 is a cross-section similar to that shown in FIG. 8 .
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and particularly to FIG. 1, an electronic circuit board assembly 10 is shown. The electronic assembly 10 comprises a printed circuit board 12 of standard construction typically composed of multiple circuitized conductive layers interleaved with layers of high dielectric material (these various layers not being shown) in the form of a laminate. One side of the board is backed with an insulator 50 and a stiffener 56 . A spring plate 52 is mounted on posts 54 and includes a screw 60 that urges the stiffener against the insulator and the PCB 12 , thereby serving to maintain the planarity of the PCB. The screw typically includes an Allen head 62 which is turned with an Allen-head wrench. Turning the screw 60 in one direction increases the spacing between the middle of the spring plate and the stiffener, thereby increasing the pressure exerted by the spring plate on the stiffener at the posts 54 . Turning the screw 60 the other way decreases this spacing and, thus, the applied pressure. Mushroom slots (not shown) along the sides of the spring plate allow the spring plate to engage the posts 54 and to be held in place by end caps 64 .
On the opposite side of the PCB 12 is an electrical module 14 . An interposer 16 separates the module 14 from the PCB 12 . A heat conductive cap 28 is placed on top of the module and interfaces with a heat sink 32 . The heat sink typically includes heat transfer fins 38 to dissipate heat generated during the operation of the assembly. The entire assembly is clamped together by posts 54 that extend through holes passing through the various components and secured in place by nuts (not shown).
FIG. 2 shows a sub-assembly 110 comprising an electronic module 14 and an interposer 16 . The module 14 is made from a ceramic material. The interposer 16 is comprised of two elements, an insulator and the electrical spring elements (herein shown as contact springs 34 ). The interposer is generally planar and is made from plastic or similar material, such as a polyphenylsulfide resin having good mechanical strength and dimensional stability. It serves to electrically and mechanically isolate the module 14 from the PCB (not shown) and to position the springs 34 . The interposer 16 includes a first planar surface 18 in contact with a corresponding surface (not shown) of the PCB, and a second surface 20 facing a first surface 26 of the module. A cap 28 covers the second surface 30 of the module. A heat sink 32 is shown in contact with the cap 28 . A plurality of contact springs 34 serve to keep the module accurately positioned with respect to the board. These springs also provide electrical continuity between contact sites on the module and corresponding contact pads on the circuitized surface of the PCB. The clamp provides a compressive clamping force to the subassembly in the manner shown in FIG. 1
When the module and the interposer are clamped together, the clamping force F c . is distributed over the entire contact surfaces if they are fully coplanar. When the surfaces are not coplanar, as shown in FIG. 2, the force within the area of contact between the ceramic module and the interposer is increased substantially, possibly causing one or more cracks 40 to form on the second surface 30 of the module in compression. These cracks could eventually lead to failure of the module 14 and the entire assembly 10 .
Turning now to FIG. 3, there is shown the sub-assembly 110 a comprising a printed circuit board 12 , a ceramic module 14 and an interposer 16 . The interposer includes a first planar surface 18 adapted to contact a corresponding surface of the PCB 12 and a second surface 20 facing the convex surface 26 of the module. A cap 28 covers the second surface 30 of the module and is sealed thereto with a sealant 72 , such as Sylgard. The heat sink 32 is shown in contact with the cap 28 . As before, contact springs 34 provide electrical continuity between contact sites 15 on the module and corresponding contact pads 13 on the circuitized surface of the PCB. A pair of stop members 42 are positioned at the edges of the interposer and contact the periphery 44 of the module. These serve to limit the rotation or rocking movement between the module and the interposer caused by the mass of the heat sink 32 when the sub-assembly is subjected to shock and/or vibration.
The addition of the two stop members 42 serves to limit the rocking motion between the convex contact surfaces of the module and the interposer, provided the clamping force is sufficient to keep one or both of the stop members in contact with the convex surface of the module. The combined height of the stop members should correspond to the curvature of the convex surface, whereby the stop members engage the perimeter of the module without the module contacting the interposer with any more than a minimum amount of pressure when the total clamping force equals the nominal contact normal force times the number of contact springs 34 .
FIG. 4 is an enlargement showing the metal cap 28 joined to the ceramic module substrate 14 with an adhesive sealant 72 , such as Sylgard®. An edge stop 42 extends at right angles to the interposer 16 and contacts the edge 44 of the module 14 . Preferably, the stop 42 is positionally aligned with the cap 28 on opposite sides of the module to minimize bending stress in the module. The edge stop 42 co-acts with a corresponding edge stop (not shown) on the opposite side of the interposer to restrict any rocking motion between the module 14 and the interposer 16 caused by shock or vibration to the assembly. It should also be understood that the edge stop may consist of a one-piece ring extending around all edges of the module.
FIGS. 5 and 6 show a module 14 joined to an interposer 16 by a plurality of suspension springs 66 . Heat is transferred from the module 14 to the heat sink 32 . The interposer 16 is shown as being generally planar with raised edges 68 forming a housing in which the module is suspended. Two springs connect each edge of the module to a corresponding edge 68 of the interposer housing. The force required to cause the module to slide in a given direction against the planar surface of the interposer is equal to the summation of forces of the springs acting perpendicular to the direction of motion, plus any clamping force applied perpendicular to the plane shown multiplied by the coefficient of friction between the two surfaces. Added to this is the spring force of any spring elements (not shown here) acting perpendicular to the direction of motion multiplied by the coefficient of friction for each spring element.
FIGS. 7 and 8 show the configuration of FIGS. 5 and 6 wherein the springs 66 on two sides of the interposer housing 68 are replaced by edge restraints 70 . According to the teachings of the present invention, these edge restraints are positioned so that the conductive sites on the module are aligned, whereby the pads are centered with respect to the contact spring elements (not shown) and the pads on the printed circuit board (not shown). By using these restraints 70 on two contiguous edges of the housing 68 , the summation of forces in the x-plane are equal to zero.
Among the benefits that accompany the use of these restraints are 1) the alignment springs do not cancel each other out; 2) better absolute positional tolerance is achieved, and 3) during vertical shock, the remaining alignment springs still contribute toward assisting module motion.
The invention contemplates the use of the stop members for z-axis motion, and the restraints for motion control in the x-y plane, either together or separately. For example, turning to FIG. 9, a sub-assembly 10 is shown wherein a module 14 is suspended within a interposer housing 68 by springs 66 along two contiguous sides and edge restraints 70 along the other two sides. The module 14 is shown with the surface 26 having a convex curvature. Stop members 42 extend at right angles to the planar surface of the interposer 16 into contact with the periphery 44 of the module 14 to prevent rocking motion. Thus, the combined effect of the restraints 70 and the stop members 42 serve to minimize the micro-motion that can occur when the assembly is subjected to shock and/or vibration.
The specific details and operation of the assembly are known to persons of ordinary skill in the art and do not comprise a part of the present invention, except to the extent that these details and operation have been modified to become part of the present invention, and to interengage with other components of the system. The specific details, including the programming of the individual computers or processors in which the present invention is used, are not deemed to comprise a part of the present invention.
While the invention has been described in combination with embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing teachings. Accordingly, the invention is intended to embrace all such alternatives, modifications and variations as fall within the spirit and scope of the appended claims. | An electronic subassembly comprises a printed circuit board and an electronic module, particularly a ceramic module, electrically connected to one another through a planar interposer. The interposer comprises an insulator sheet and electrical spring elements joining contact sites on the module with contact pads on the PCB. The invention includes modifications that improve the integrity of electrical connections between the printed circuit board and the electronic module. This is achieved by compensating for non-planarity between the surfaces of the interposer and the module, particularly resulting from a convex curvature of the module, by minimizing relative movement, such as rocking in the x-z and y-z planes. It also includes modifications to the suspension of the module within the interposer housing to reduce the effects caused by any sliding that may occur between the interposer and the module in the x-y plane. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application relates to U.S. patent application Ser. No. 13/176,842, filed Jul. 6, 2011, entitled “Pipeline Power Gating,” naming inventors Daniel W. Bailey et al., which application is incorporated herein by reference in its entirety.
BACKGROUND
[0002] 1. Field of the Invention
[0003] This invention relates to power savings in integrated circuits and more particularly to reducing leakage current during runtime.
[0004] 2. Description of the Related Art
[0005] Power consumption in integrated circuits can be attributed to both actively switching circuits and to idle circuits. Even when circuits are idle, leakage current from the transistors results in undesirable power consumption. Previous solutions to saving power have identified large architectural features that have been idle for a period of time and have implemented power savings in such circuits by reducing the voltage being supplied and/or the frequency of clock signals being supplied to the unused circuitry. For example, in a multi-core processor, one or more of the cores may be placed in a lower power consumption state by reducing the supplied frequency and/or voltage while maintaining active other functional blocks, such as input/output blocks. However, particularly in battery driven devices, such as mobile devices, laptops, and tablets, finding additional ways to save power is desirable to extend battery life, reduce heat generation, and ease cooling requirements. Even in desktop or server systems, reducing power consumption leads to reduced heat generation, cost savings by reducing electricity use, and reduced cooling requirements. Power saving considerations continue to be an important aspect of integrated circuit and system design.
SUMMARY OF EMBODIMENTS OF THE INVENTION
[0006] Additional power savings can be achieved by focusing on small-grained features of the integrated circuit. One embodiment provides a method of reducing leakage current that includes waking a first plurality of gates coupled between first source storage elements and second destination storage elements, to allow current flow in the first plurality of gates, the waking in response to assertion of any of one or more first source clock enable signals associated with the first source storage element. The method includes waking a second plurality of gates, coupled between second source storage elements and second destination storage elements plurality, to allow current flow in the second plurality of gates, in response to assertion of any of one or more second source clock enable signals associated with the second source storage elements. The method further includes waking a third plurality of gates, in response to assertion of any of the one or more first source clock enable signals and waking the third plurality of gates in response to the assertion of the any of the one or more second source clock enable signals. The third plurality of gates are slept to reduce leakage current in the third plurality of gates in response to, at least in part, all of the one or more first and second source clock enable signals being deasserted.
[0007] In another embodiment, an apparatus includes a plurality of first power-gated gates coupled between first source storage elements and first destination storage elements. A plurality of second power-gated gates are coupled between second source storage elements and second destination storage elements. A plurality of third power-gated gates are coupled between at least one of the first or second source storage elements and the first and second power-gated gates. At least one power gate is coupled in series between a power supply node and the third power-gated gates, the power gate to reduce current flow through the third power-gated gates in response to a power gate control signal indicating a sleep state and to allow current flow through the power-gated gates in response to the power gate control signal indicating a wake state. Control logic for the at least one power gate is configured to cause the power gate control signal to indicate the wake state based on first and second control signals associated with the first and second power gated gates that respectively cause the first and second power-gated gates to enter sleep and wake states.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention may be better understood, and its numerous objects, features, and advantages made apparent to those skilled in the art by referencing the accompanying drawings.
[0009] FIG. 1 shows a high level diagram of an integrated circuit suitable for using embodiments of the invention.
[0010] FIG. 2 illustrates a high level diagram of power-gating logic gates according to an embodiment of the invention
[0011] FIG. 3 illustrates a timing diagram associated with the embodiment of FIG. 2 .
[0012] FIG. 4A illustrates an exemplary power-gating approach.
[0013] FIG. 4B illustrates an exemplary power-gating approach utilizing additional power gates.
[0014] FIG. 4C illustrates a high level diagram of an exemplary power-gating power approach in which timing constraints are eased by eliminating gates from being power gated.
[0015] FIG. 5 illustrates a configuration in which gates in Group A and gates in Group B are power gated and gates in Group AB are not power gated.
[0016] FIG. 6 illustrates a configuration in which logical coverage is increased over the configuration of FIG. 5 .
[0017] FIG. 7 illustrates another configuration for multiple groups providing improved logical coverage as compared to the configuration of FIG. 5 and improved power savings compared to the configuration of FIG. 6 .
[0018] FIG. 8 illustrates additional details of Group AB found in one embodiment.
[0019] The use of the same or similar reference symbols in different drawings indicates similar or identical items.
DETAILED DESCRIPTION
[0020] Power gating groups of gates achieves additional power savings during run-time operation by reducing the leakage current of transistors in the gates. In one embodiment a power gate is formed by a transistor (or many transistors in parallel) that are in series between the power-gated gates and their power supplies, e.g., VDD and/or GND. The power gate(s) are then selectively controlled to disconnect the gates from VDD and/or ground so the leakage current can be reduced when the gates are not being used.
[0021] Referring to FIG. 1 , a high-level block diagram illustrates an integrated circuit 101 such as a microprocessor, which includes multiple macro architectural features 102 such as processing cores, whose power can be controlled by placing them in power states that provide varying levels of performance, from a sleep state to a fully powered state. In addition, one or more of the macro architectural features have groups of gates 103 that can be controlled to reduce power consumption during the full (or a reduced) operational state during run time.
[0022] FIG. 2 illustrates an exemplary embodiment of how the groups of gates can be controlled during run time to decrease power consumption. Referring to FIG. 2 , nFET power gate 201 is in series between the power-gated gates 203 and GND. The power-gated gates 203 correspond to the group of gates 103 shown in FIG. 1 . The gates that are power gated are typically AND, OR, NOR, NAND, and similar logic gates and are represented in FIG. 2 as power-gated gates 203 . When the gates 203 are idle, the power gate 201 can be turned off, reducing the voltage across the gates and thereby reducing the leakage current from the gates. In addition, or instead of using the nFET 201 , a pFET 202 can be used in series with VDD, and switched off to reduce the voltage across the gates, thereby reducing the leakage current.
[0023] A significant issue with run-time power gating is having adequate time to transition the gates from sleeping to fully powered, i.e., having enough time to wake. That is, when power gate 201 is turned on, the power-gated gates take time to fully charge to their fully powered state in response to power gate 201 (and/or 202 ) turning on. One approach is to include sufficient timing margin in the design, e.g., a guard band in the timing design, to ensure the gates are fully powered. However, such a timing penalty is generally unacceptable in high-performance integrated circuits such as microprocessors.
[0024] Control logic 205 monitors the clock gate enables 221 and 223 of the source flip-flops 207 to determine when to wake, and when to sleep the power-gated gates. The number of clock gate enables shown is illustrative and other numbers of enables may be utilized based on design requirements. Note that the AND gate 208 may also be considered part of control logic 205 and helps control the clocking of the destination flip-flops as described further herein. Note that while flip-flops are shown in FIG. 2 , any source and destination storage elements, such as latches, may be used instead of, or in addition to, the flip-flops shown in FIG. 2 .
[0025] FIG. 2 illustrates the basic operation and construction of an exemplary embodiment. A chosen set of destination flip-flops 209 determines the set of gates 203 that can be power gated. That is, a gate can be power gated if all of its output paths terminate exclusively at one or more of the destination flip-flops 209 . Gates with output paths that go to places other than destination flip-flops are not power gated. For example, the inverter 215 has an output path 217 that goes somewhere other than destination flip-flops 209 , e.g., to a different flip-flop, latch, or output port. Accordingly, inverter 215 is not included as part of the power-gated gates 203 . In an exemplary embodiment the control logic 205 is a state machine that controls the power gate, monitors the clock gate enables and determines when to wake the power-gated gates, and when the power-gated gates can sleep.
[0026] Consider an initial state of sleep. In the initial sleep state shown in FIG. 2 , destination flip-flops 209 are blocked from clocking and the power-gated gates 203 are sleeping. The term sleeping refers to the power gate 201 (or 202 ) being turned off to reduce leakage current in the power-gated gates 203 . In the sleeping state the state machine in the control logic 205 is in a first state in which the WAKE signal is deasserted. FIG. 3 illustrates a timing diagram associated with the circuits shown in FIG. 2 . The term “wake” refers to the power gate 201 (and/or 202 ) being turned on to allow current to flow in the power-gated gates 203 .
[0027] Referring to FIG. 3 , assume a clock signal CLK 301 on clock signal line 224 . Latches 226 and 228 are used to supply the enable signals ENA 1 221 and ENA 2 223 for the clock signals for source flip-flops 207 . The enable signals are ANDed with the clock signals in AND gates 230 and 232 . Gates 203 wake in response to assertion of any of the source flip-flop clock gate enables 221 or 223 (shown at 302 ) after the delay through OR gates 225 , 227 , and 229 . The state machine flip-flop 231 asserts its output on the rising edge of the next cycle at 304 , thus changing to a second state. The assertion of the output of the flip-flop 231 results, after a delay, in the assertion of the DEST_ENA_ 3 signal at the output of the AND gate 208 at 306 . The destination flip-flops 209 are then clocked after the delay through latch 210 and AND gate 212 . The enable (ENA 3 ) for the destination flip-flops is assumed to be asserted at that time. Using the state machine, there is at least a one-cycle delay between assertion of the source enables at 302 and the assertion of the destination enable at 306 , allowing the power-gated gates time to fully charge before the destination flip-flop clocks are unblocked and clocked.
[0028] The power-gated gates 203 are held awake by the control logic 205 until the destination flip-flops are clocked. Once destination flip-flops are clocked after DEST_ENA_ 3 236 is asserted at 306 and the source enables 221 and 223 are deasserted, the output of the state machine flip-flop deasserts at 308 at the rising clock edge, returning to the first state, causing the power-gated gates to sleep by deassertion of the WAKE signal at 310 . Any further clocks for the destination flip-flops 209 are blocked by AND gate 208 until source flip-flops are clocked again. The destination flip-flops will not change, of course, if the source flip-flops do not change. The blocking function allows a full clock period before destination flip-flop inputs are consumed.
[0029] An embodiment may have multiple destination enables. If so, there is a need to wait until all destination clock enable signals have asserted before putting the power-gated gates to sleep. Since conceivably the destination enables can arrive at different times, the signals can be stored in flip-flops and then reset when all bits have been asserted at least once and supplied to the logic to cause sleep through the flip-flop 231 . In an embodiment, bits could be encoded to save on the number of flip-flops.
[0030] FIG. 4A illustrates an embodiment in which the power-gated gates 403 between source flip-flop 402 and destination flip-flop 404 are coupled to a single power gate 405 . In FIG. 4B multiple power gates 407 and 409 are used. If there are a large number of power-gated gates, the distribution of WAKE to the power gates may take several stages of buffers. FIG. 4B shows how timing requirements can be relaxed by partitioning gates into critical timing gates (attached to WAKE 1 ) and non-critical timing gates (attached to WAKE 2 ). Thus, power gate 407 receives WAKE 1 and power gate 409 receives WAKE 2 . Gates temporally closest to the source flip-flops are most critical. In the embodiment shown in FIG. 4B , the power gate for the critical gates receive WAKE 1 using no buffers (or fewer buffers) as compared to WAKE 2 . For ease of illustration, WAKE 2 is shown being generated with one buffer and WAKE 1 with no buffers. Other number of buffers may be required depending on the particular implementation and the number of power gates driven by each of the wake signals.
[0031] Timing requirements are aggressive, but can be relaxed. The OR of the enables of the source flip-flops supplies the state machine flip-flop 231 . The clock for the flip-flop 231 can be delayed, however, since it initiates the sleeping function, not the waking.
[0032] A second timing constraint is that the gates should be fully powered by the time they are used, or timing can suffer. They should be wakened by the time the source flip-flops outputs can transition. This timing constraint can be relaxed by not power gating stages of gates immediately following the source flip-flops. Referring to FIG. 4C , gates 411 and 415 are not power gated and not included with power-gated gates 417 to provide additional timing margin for the control signal WAKE to wake the power-gated logic gates. Both of these timing relaxation techniques shown in FIGS. 4B and 4C reduce the leakage savings. As shown in FIG. 4C , the setup requirement can be relaxed by trading off coverage of how many gates are subject to power gating.
[0033] The active power gating approach described herein is applicable to microprocessor design, but is widely applicable to circuit design generally. Because the techniques herein can be generally applied to digital circuitry, the active power gating described herein can achieve high coverage, which in turn means more power savings. Timing impact is modest. The timing impact results from a term being ANDed in AND gate 208 in the clock enable path, and there is additional load for the one or more source enable signals from the OR tree. As clock gating efficiency improves over current approaches, the active power gating herein will automatically improve in terms of its impact on leakage savings.
[0034] Power gating described herein may lead to higher use of LowVT (LVT) gates, or even UltraLowVT (ULVT) gates, within power-gated domains because leakage power is selectively and transiently reduced. Active-mode power gating puts leakage power on par with dynamic power when making performance-power tradeoffs.
[0035] An additional benefit of the approach described in FIG. 2 is that dynamic power is likely to be reduced, too, because of the clock blocking function by AND gate 208 on the clock for the destination flip-flops. That is, if the destination clocks are blocked by the control logic 205 , additional power savings occurs.
[0036] As has been described above, pipeline Power Gating (PPG) reduces leakage of inactive circuits during run time. In certain embodiments, it is possible to increase the logical coverage of PPG while preserving the original power savings so that leakage savings is increased.
[0037] Referring to FIG. 5 , consider the illustrated configuration in which gates in Group A supplying destination flip-flops 501 and gates in Group B supplying destination flip-flops 503 are power gated. Gates in Group AB are not power gated because they terminate in more than one set of destinations, both Group A destination flip-flops and Group B destination flip-flops. Group AB gates must be awake anytime either Group A or Group B destination flops are clocked.
[0038] Another important concern is that power-gated domain outputs must not drive fully powered gates without isolation gates. The consequence would be crossover current and possible compromise of reliability. An isolation gate is a gate that is configured to selectively ignore an input, and requires a full-rail signal to control it. For Group A and Group B gates, the isolation gates are the destination flops, and the isolation controls are the clocks. Adding isolation gates to the outputs of Group AB gates would impact timing if generally applied.
[0039] As shown in FIG. 6 , logical coverage can be increased by combining the multiple sets of destination flip-flops into a single set of destination flops. As shown in FIG. 6 , groups of gates A and B are subsumed into a larger Group AB. The circuit shown in FIG. 6 increases the logical coverage, but the main problem with this approach is that static and dynamic power savings may actually be reduced. Group A gates are now likely to be slept less often than in the original configuration since they are awakened by any of the Group A and Group B source enables. Similarly, dynamic power is likely to increase because Group A destination flops are clocked when either ENA 3 _A or ENA 3 _B is asserted, instead of just ENA 3 _A. The same static and dynamic disadvantages apply to Group B gates.
[0040] In addition, there are two other problems with the approach shown in FIG. 6 . First, it is unclear which group of gates should be combined when there are more than two sets of destinations. Consider if there are also Group C, AC, BC, and ABC gates. If all groups are subsumed into a Group ABC, then the power savings problem described above is worse. If Group AB is formed, then Groups AC, BC, and ABC are not included in the logical coverage (without duplication of logic). The second problem is that the register transfer language (RTL) description must be rewritten to restructure the logic as groups are combined.
[0041] FIG. 7 shows an exemplary approach for combining power-gated groups that provides improved logical coverage and power savings. Unlike the circuit in FIG. 6 , in FIG. 7 Group A and Group B gates are power gated as often as they are in the original configuration in FIG. 5 . Also, Group A and Group B destination flip-flops are clocked as often as they are in the original configuration. Therefore, in FIG. 7 , Group AB gates add to the leakage savings. In this approach, anytime either Group A or Group B gates are awake, Group AB gates are also woken. The function of the AND gate 701 driving the Group A power gate is to ensure Group AB gates are awake before Group A gates are woken, i.e., the AND is for power deracing. The same principle applies to the AND gate 703 driving the Group B power gate.
[0042] The approach described by FIG. 7 provides another advantage in that the formation of any groups does not prevent the formation of other groups. If there are also Group C, AC, BC, and ABC gates, they can all be power gated separately using similar logic.
[0043] Note that the preferred approach reduces timing margin by adding an AND gate delay in the power gate enable path. Also, the register transfer language (RTL) description of the circuit has to be updated as combined groups are added. But the approach of FIG. 7 increases the logical coverage and leakage savings from Pipeline Power Gating without decreasing the dynamic power savings, and the approach is scalable for all combinations of groups.
[0044] FIG. 8 illustrates an embodiment in which flip-flops 502 and 504 supply AND gate 801 in Group AB. Other logic gates are typically included in Group AB but FIG. 8 only shows AND gate 801 for ease of illustration. As can be seen in FIGS. 5-8 , source storage element 502 is a source element for both Group A and Group B through the combinational logic in Group AB. Similarly, source storage element 504 is a source element for both Group A and Group B supplied through combinational logic in Group AB. Thus, source storage elements such as flip-flops 502 and 504 may serve as source storage elements for different groups of destination storage elements 809 and 811 . Thus, assertion of either of the clock enable signals ENA 1 _B or ENA 1 _A wakes both Group A and Group B (and Group AB). The power savings can be seen in that Group A can remain power gated when ENA 2 _B is asserted and Group B can remain power gated when ENA 2 _A is asserted. Group AB is wakened whenever any of the enables for Group A or Group B are asserted. Thus, Group AB can be slept when both Group A and Group B are slept, saving power as compared to FIG. 5 . In addition, Group A can be slept when Group AB and B are awake and Group B can be slept when Group A and AB are awake, thus providing power savings as compared to FIG. 5 or 6 .
[0045] While circuits and physical structures have been generally presumed in describing embodiments of the invention, it is well recognized that in modern semiconductor design and fabrication, physical structures and circuits may be embodied in computer-readable descriptive form suitable for use in subsequent design, simulation, test or fabrication stages. Structures and functionality presented as discrete components in the exemplary configurations may be implemented as a combined structure or component. Various embodiments of the invention are contemplated to include circuits, systems of circuits, related methods, and computer-readable medium having encodings thereon (e.g., HDL, Verilog, GDSII data) of such circuits, systems, and methods, as described herein. Computer-readable medium includes tangible computer readable medium e.g., a disk, tape, or other magnetic, optical, or electronic storage medium. In addition to computer-readable medium having encodings thereon of circuits, systems, and methods, the computer-readable media may store instructions as well as data that can be used to implement the invention. Structures described herein may be implemented using software executing on a processor, firmware executing on hardware, or by a combination of software, firmware, and hardware.
[0046] The description of the invention set forth herein is illustrative, and is not intended to limit the scope of the invention as set forth in the following claims. Other variations and modifications of the embodiments disclosed herein may be made based on the description set forth herein, without departing from the scope and spirit of the invention as set forth in the following claims. | A first and second plurality of gates are coupled respectively between first and second source storage elements and first and second destination storage elements. The first and second plurality of gates are slept to reduce leakage current in the plurality of gates under certain conditions by turning off respective one or more transistors between the first and second plurality of gates and power supplies. A third plurality of gates are maintained in a reduced leakage current state (sleep state) or regular state (wake state) based on conditions associated with the source and destination elements for the first and second plurality of gates. | 8 |
RELATED APPLICATIONS
This application claims priority under 35 U.S.C. §119(e) from Provisional Patent Application No. 60/144,293 filed Jul. 16, 2000.
FIELD OF THE INVENTION
This invention relates generally to fireplaces and more particularly to a glass enclosure for closing the front of an open fireplace box.
BACKGROUND OF THE INVENTION
Fireplaces have been used for centuries as a means for providing heat, for cooking and for simply decorative purposes. Modern fireplaces typically have a front enclosure panel that may be sealed to the front of the fireplace box, or which may include operable doors enabling access into the fireplace box.
The fireplace box that defines the combustion chamber can assume a number of different configurations. In traditional wood burning fireplaces of brick or mortar construction, the combustion chamber generally extends over the full height of the. fireplace box, and a log holding grate rests on the floor of the combustion chamber. For gas burning fireplaces, the burner assembly and associated gas supply mechanisms are typically located below the floor of the combustion chamber but often still within the open cavity defined by the fireplace box. A number of fireplaces also include a heating plenum that pulls room air into the plenum near the bottom of the. fireplace box, heats the air, and emits the heated air back into the room near the top of the fireplace box. In order to provide an aesthetically pleasing design for the fireplace front enclosure, most such enclosures provide wide metal panels near the top and bottom portions of the open front fireplace box assembly, to cover or mask the unsightly looks of the mechanisms or openings located at those positions. Such molded panels may be typically coated with brass, bronze or anondized metal finishes. The vertical area between the upper and lower decorative metal panels, generally contains one or more panels of glass that can be of a nature that forms a seal with the front of the fireplace box or which includes operable door panels for gaining access to the combustion chamber.
It would be desirable from both aesthetic and cost viewpoints to eliminate the upper and lower metal decorative panels of a fireplace front enclosure and to form the entire front fireplace box enclosure from glass, except for the relatively narrow surrounding framework. The present invention addresses this need.
SUMMARY OF THE INVENTION
The present invention provides a glass surround or enclosure for the front of a fireplace box. The surround includes a glass enclosure or panel sized and configured to correspond to a front of the fireplace box, a support for securing the glass enclosure adjacent to the front of the fireplace box, and a pattern arrangement disposed on the glass enclosure for masking at least a portion of the contents of the fireplace box. In one aspect, the glass enclosure is comprised substantially entirely of glass, except for the support arrangement. The enclosure can be in the nature of a sealing panel, for sealing the open front of the fireplace box, or can include operable glass door members for enabling access into the fireplace box. The enclosure member can be configured for attachment to any type of fireplace assembly, whether of masonry or brick construction, of prefabricated modular construction, of retrofit insert construction for existing fireplaces, or the like.
The surround enclosure panel includes a support for securing the enclosure adjacent to the front of the fireplace box, for example, a heat resistant adhesive, or conventional mechanical fasteners, such as bolts or the like. In another aspect, the support includes an outer frame of relatively narrow or a thin profile configuration when viewed from the front of the panel, that operatively peripherally supports one or more panels of glass. The glass panels substantially fill or close the area peripherally defined and encircled by the frame. The frame is preferably made from a metal material; however, the construction need not necessarily be of metal. The frame includes fasteners that can be in the form of one or more hanger members for detachably securing the frame and the glass carried thereby to the front of a fireplace box.
Silk screened patterns of various shapes and configurations can be applied to the back or inner surfaces of the glass panel(s) at selected positions therealong, to visually mask portions of the fireplace box when viewed from outside of the enclosure. For example, a rectangular surround enclosure panel may include a screened rectangular portion adjacent the top of the glass panel(s) for masking unsightly structures near the top edge of the fireplace box, and might include a similar rectangular silk screened portion near the bottom of the glass panel(s) for masking the burner assembly structure in a gas burning fireplace. Alternatively, or in addition to the use of silk screening for masking out unsightly portions of the fireplace box, the screening may be applied to the glass in various patterns, shapes and/or in graphical manner soas to provide a desired aesthetic look or viewing area through the glass and into the combustion chamber when the glass is illuminated from within the fireplace box, as it might be when there is a flame burning within the combustion chamber.
Some embodiments of the invention are particularly well suited for gas burning fireplaces to mask the burner assembly and associated gas supply mechanisms or heating. Other embodiments are particularly well suited for modern wood burning fireplace box inserts that include heating plenums, and are designed to cover or mask the unsightly looks of the mechanisms or openings.
These and other features of the invention will become apparent to those skilled in the art upon a more detailed description of preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to the drawings wherein like numerals represent like parts throughout the several views:
FIG. 1 is a front elevation view of a first embodiment of a glass surround enclosure according to the principles of this invention;
FIG. 2 is a top elevational view of the glass surround enclosure of FIG. 1;
FIG. 3 is a right side elevational view of the glass surround enclosure of FIG. 1;
FIG. 4 is a cross-sectional side view of the glass surround enclosure of FIG. 1, generally taken along 4 — 4 in FIG. 1;
FIG. 5 is a front elevational view of a second embodiment of a glass surround enclosure of the present invention;
FIG. 6 is a top elevational view of the glass surround enclosure of FIG. 5;
FIG. 7 is right side elevational view of the glass surround enclosure of FIG. 5;
FIG. 8 is a cross-sectional end view of the glass surround enclosure of FIG. 5, generally taken along the Line 8 — 8 of FIG. 5; and
FIG. 9 is a diagrammatic schematic cross-sectional side view of the enclosure of this invention illustrated mounted to a fireplace box constructed of molded ceramic material and installed within a wall.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the figures, a first embodiment of a glass surround enclosure generally constructed according to the principles of this invention is illustrated at 10 in FIGS. 1-4. The enclosure includes a support for securing the enclosure adjacent to the front of the fireplace box, for example, a heat resistant adhesive, or conventional mechanical fasteners, such as bolts or the like. In an alternative embodiment, the support includes an outer frame 11 of relatively narrow or a thin profile configuration when viewed from the front of the panel, that operatively peripherally supports one or more panels of glass. The peripheral, relatively narrow profile frame 11 is sized to cooperatively engage the front surface of a fireplace box soas to cover the surface area defined by the open front of the fireplace box. An upper panel of glass 12 is mounted to the inner surface of the frame 11 , and a pair of hinged door assemblies 13 and 14 are respectively mounted to the frame 11 by vertically spaced hinge pairs 15 and 16 respectively. The left hinged door assembly 13 includes a pair of pivotally connected glass panels 13 a and 13 b hinged about upper and lower hinge pairs 15 a and 15 b to the left side of the frame 11 . The right door assembly 14 includes a pair of glass door panels 14 a and 14 b pivotally connected to one another and supported by the upper and lower hinges 16 a and 16 b to the right side portion of frame 11 . Each of the hinged door assemblies 13 and 14 includes a handle 17 and 18 respectively for opening and closing the hinged door assemblies.
The upper edges of the door assemblies 13 and 14 include a cap of extruded decorative metal 20 , and their lower edge is also trimmed by a thin strip of decorative metal 21 . In the embodiment illustrated, their is a narrow gap 22 between the lower edge of the upper glass panel 12 and the upper edge of the metal strip 20 . There is also a small gap 23 between the lower edge of the metal strip 21 of the door assemblies and the upper edge of the frame 11 .
The back or inside surface of the upper panel 12 contains an applied silk screen pattern, generally indicated at P 1 that, in the preferred embodiment, forms an opaque image through the upper glass panel 12 when viewed from the front of the assembly. Similarly, there is a rectangular silk screen pattern P 2 applied to the inner surface of the glass panel door members 13 and 14 adjacent their respective lower edges that is also visually opaque to an observer looking through the glass doors from the front of the surround enclosure. When there is no light being emitted from the fireplace box cavity that the glass surround is covering, one does not readily perceive the existence of the silk screen coating on the back of the glass surfaces of the enclosure. Therefore, the overall visual effect to an observer looking at the glass enclosure, is that the enclosure is simply a full glass panel that provides a pleasing visual effect that is generally uninterrupted by heavy metal panels as was the case with prior art enclosures. However, when light is emitted from within the fireplace box and through the glass surfaces of the surround 10 , the silk screened portions will prevent the light from passing therethrough and provide a masked visual effect to the outside viewer, as defined by the shape and pattern of the silk screen patterns applied to the glass. It will be appreciated that while simple rectangular silk screen configurations have been illustrated in FIG. 1, other patterns could equally well have been applied to the glass, such as circular or diamond shaped configurations, or the like.
FIGS. 3 and 4 illustrate connection of a support bracket 30 to the frame 11 . The bracket 30 has a pair of “J” hooks 30 a and 30 b that simply slide within receptor slots (not illustrated) appropriately positioned in the front surface of the fireplace box to which the glass surround enclosure 10 is to be secured. In the preferred embodiment, there are a pair of such support brackets 30 , one each being secured to each of the upright end portions of the frame 11 . It is illustrated in FIG. 3, there is also a toggle switch 32 mounted to the right side portion of the frame 11 which can be used for multiple purposes such as activating a blower, energizing a gas burner system, or the like.
A second embodiment of a glass surround enclosure 10 ′ configured according to the principles of this invention is illustrated in FIGS. 5-8. Parts similar in construction and function in the second embodiment as compared to the first embodiment are illustrated by the same numerical designations, followed by a prime designation. The glass surround enclosure 10 ′ is basically the same in construction and function as enclosure 10 of the first embodiment, except that the upper member 11 a of the frame 11 ′ is arcuately shaped, and the upper glass panel 12 ′ has a curved upper surface to match the arcuate shape of the upper frame member 11 a . As with the first embodiment, the entire back surface of the upper glass panel 12 ′ is coated by silk screening.
It will be appreciated by those skilled in the art, that the silk screening applied to the glass can assume many different forms. For example, the consistency of the silk screened pattern could be solid, could be a dotted configuration as for example applied by a laser jet applicator, or like. Further, the patterns applied to the glass need not necessarily be silk screened or even opaque patterns, but could be patterns formed by other application techniques such as by etching of designs or the like into the glass. Further, as stated above, the designs need not be peripheral or specific shape-defining patterns, but could be in the nature of monograms, letters, or other configurations.
FIG. 9 illustrates the surround enclosure 10 as it might appear in cross-section as mounted to the front of a fireplace box assembly 40 . The fireplace box assembly 40 is of a type that is molded from a highly insulative ceramic material as disclosed in pending U.S. patent applications Ser. No. 08/538,866 filed on Jan. 19, 1996 entitled Universal Non-Porous Fiber Reinforced Combustion Chamber and U.S. patent application Ser. No. 09/024,285 filed on Jul. 6, 1999 entitled Low Cost Prefabricated Fireplace With Fiber Insulation Firebox. The firebox assembly 40 is illustrated as it would appear mounted in a wall of a building. However such fireplace box assemblies are also ideal for insertion within existing fireplaces and enclosures for retrofit applications. As an example only, in such applications it would be desirable to have a front enclosure 10 such as that disclosed in this application, having an upper silk screen masked area P 1 for masking view of the structure in the area illustrated at 42 , and a lower silk screen masked area P 2 for masking the structure in the area illustrated at 44 . While this invention is particularly attractive for use in association with “insert” type fireplaces, its principles are not limited to such application. Other applications for the enclosure will be apparent to those skilled in the art.
These and other features of the invention will become apparent to those skilled in the art. The specific examples illustrated are not intended to be limiting to the invention, but are intended only for the purposes of providing specific examples illustrating use of and principles related to the invention. The invention is not to be limited in any manner by the descriptions herein provided. Rather, the invention is to be accorded the full scope and protection of the appended claims. | A front surround or enclosure for overlying the open front of a fireplace box is disclosed. The enclosure has a relatively narrow peripheral frame that carries one or a plurality of glass panels that substantially fill the enclosed area defined by the outer frame. The glass panels may be rigidly secured to the frame or can be configured as operable doors. Patterns configured by silk screening or other application techniques are selectively applied, preferably to the inner surface(s), of the glass panel(s) to enhance visual appeal of the glass and/or to selectively mask the viewer's vision through the glass. Quick release brackets are provided for detachably securing the enclosure to the front of a fireplace box. | 5 |
BACKGROUND
1. Field of the Invention
The methods and apparatus of the present invention relate to indirect-heating screw conveyors.
2. Description by Direct and Indirect Heating
Removal of contaminants including volatile organic compounds from semisolid material, including soils, sludges, slurries or other particulate or granular materials, is commonly achieved by methods which include heating the material to desorb (i.e., drive off as gases) relatively volatile components. Gases thus driven off may then be recovered for sale or detoxification by, for example, burning, catalytic action or other chemical processes. An example of this technology is described in U.S. Pat. No. 4,974,528 (Barcell), which relates to a vehicle-mounted system for removing hydrocarbon contaminants from soils. Barcell describes a system in which material transported in a rotary kiln is directly heated by contact with the flame and/or hot exhaust gases from a propane burner assembly. As illustrated in Barcell, direct heating of contaminated material results in a requirement to remove both particulate matter (fines) and certain gaseous contaminants from the burner exhaust stream. These removal operations are complicated by the relatively high temperature and large volume of the exhaust stream and the toxicity of some exhaust gas components.
Indirect heating of contaminated materials, in contrast, keeps both fines and desorbed gas-phase contaminants out of the exhaust stream (if any) of the burner or other heating element. In practice, indirect heating is often accomplished by locating a heat source within the hollow shaft of a screw conveyor having external threads (flights). During screw rotation, heat can flow from the source to the screw shaft surface and thence to material in sliding contact with external portions of that surface, i.e., the flights and screw shaft surfaces between the flights (inter-flight surfaces). Simultaneously, sliding contact with the flights tends to mix the material and transport it in a direction generally parallel to the (longitudinal) axis of screw rotation.
Exhaust gases from such an indirect heating fuel burner may be confined within the hollow shaft, isolated from contact with contaminated material and contaminant vapors. This relatively clean exhaust gas can frequently be directly vented to the atmosphere after exiting the desorber. A separate (closed) recovery system may then be sized to collect only the vaporized portions of contaminated material for further processing. Because burner exhaust gases need not be so processed, any dust collectors, condensers and/or gas scrubbers associated with an indirect heating (closed) system can be smaller than analogous units used with direct-heating desorbers of similar desorbing capacity.
Thus, indirect-heating hollow screw conveyors are preferred for certain medium-temperature (i.e., about 600 to 1200 degrees F.) decontamination apparatus. Electrically heated transportable desorbers which operate in this temperature range are commercially available, but their relatively low heat source output (BTU/hour) limits throughput capacity for contaminated material. Replacement of electrical heaters with fuel burners having substantially higher heat output (e.g., up to about 50 million BTU/hour) would raise both temperature limits and throughput capacity, but high-temperature desorbers have in the past been very large. Significantly reducing the size and weight of high-temperature desorbers would require improvements in several areas.
For example, desorbers comprising relatively light-weight indirect-heating screw conveyors with high-capacity fuel burners frequently experience localized overheating due to nonuniform distribution of transported material, poor heat transfer to the transported material, and/or burner misalignment. Additionally, excessive heat flux to the screw support bearing assemblies and/or rotary drive components (e.g., motors, sprockets, chains and/or gears) may lower desorber reliability by causing premature failure of these components.
Nonuniform heat transfer to transported (contaminated) material is aggravated by suboptimal distribution of heating gas within a screw conveyor screw shaft and by poor mixing of the material and/or refractory deposits of transported material adhering to parts of the screw shaft. Such adherent deposits may reduce heat flux to certain portions of the transported material, reduce material throughput capacity, increase the torque required for screw shaft rotation, and in certain cases even jam the screw shaft. Thus, an improved desorber might address the problem of material accumulations (e.g., by reducing the screw shaft surface maximum temperature) by improving heat distribution to the screw shaft surface and by optimizing the screw shaft temperature gradient for each material desorbed. Removing existing material accumulations on screw shaft and/or conveyor wall surfaces (e.g., by scraping), and cooling beating and drive components and may also be desirable to increase desorption efficiency and reduce material accumulations on desorber (primarily screw shaft) surfaces.
SUMMARY OF THE INVENTION
The methods and apparatus of the present invention relate to high-capacity, temperature-controlled, indirect-heating screw conveyor desorbers and the screw shafts therein. Each desorber has one or more single-wall or double-wall screw shafts for facilitating desorption of volatile and semivolatile fractions from semisolid material in contact with each screw shaft outer surface. Each screw shaft includes one or more substantially helical external flights and a gas guide for optimal distribution of heating gas within the screw shaft. In certain preferred embodiments, provision for active or passive circulation of cooling fluid (preferably comprising air) within screw shaft bearing areas comprising a double-walled cylindrical portion facilitates cooling of the adjacent screw shaft bearing assemblies, rotary drive means and rotary power source(s). Maximum heating gas temperatures may be controlled by dilution of the heating gas with cooling fluid (preferably air). Optional provisions for self-cleaning of screw shaft surfaces (using breaker devices) and conveyor walls (using hardened bits) are also present in certain preferred embodiments of the invention. Application of the invention thus allows design and production of high-capacity desorbers having increased efficiency, reliability and flexibility in comparison with currently available indirect-heating screw conveyor desorbers having one or more screw shafts.
Note that as used herein, a flight comprises a substantially uninterrupted helical surface, a pitch of which is the longitudinal distance measured between successive flight surfaces separated by a single turn around the screw shaft. A flight pitch may thus vary from turn to turn in any (local) portion of the helical surface (i.e., a substantially continuously varying local flight pitch), or the pitch may be a substantially constant value in any local portion of the helical surface with different pitch values in two or more separate local portions (i.e., having at least two discrete local flight pitches). Further, each substantially helical flight may have a single substantially constant local flight pitch throughout, a substantially continuously varying local flight pitch throughout, or a combination of local portions wherein each portion may have either a substantially continuously varying local flight pitch or a substantially constant local flight pitch.
In general, a plurality of (interleaved) flights may be associated with the same longitudinal section of a gas guide or screw shaft outer surface. In such a case, the pitch of any given flight is measured, as described above, between successive surfaces of the given flight (although analogous surfaces of one or more other flights may be interleaved between the surfaces of the given flight which define the pitch measurement). Note that when a screw shaft outer surface or gas guide has more than one flight in a local portion, all of the flights present will have substantially the same local pitch, which may of course change in different local portions. The longitudinal screw shaft length over which at least one external flight extends, regardless of the flight pitch(es), is the effective longitudinal flight length.
Preferred embodiments of screw conveyors according to the present invention employ a counter-current flow pattern, wherein material is carried by external flight surfaces in a direction substantially opposite that of the flow of heating gas in the conveyor (desorber). That is, the conveyed material moves from the second screw shaft end (which is proximate the second screw shaft bearing area) substantially toward the end of the screw shaft through which heating gas is introduced into the screw shaft for distribution in the gas guide (i.e., the first end). This (first) end of each screw shaft is also proximate to the screw shaft wall first end and the first screw shaft bearing area which is coupled thereto.
Screw shafts of the present invention are substantially circular in cross-section and substantially symmetrical about a substantially centered longitudinal rotational axis. The relatively larger diameter screw shaft embodiments are preferably double-walled for at least a portion of their length outside of the screw shaft bearing areas. Screw shaft bearing areas, whether on single-walled or double-walled screw shafts, may themselves be single walled or each may comprise a double-walled cylindrical portion to facilitate cooling. In double-walled screw shafts, a gas guide is coupled between the screw shaft wall and a substantially coaxial internal chamber wall (which together form a double-walled portion of the screw shaft outside of the screw shaft bearing areas).
One end of the central cavity within a double-walled screw shaft (i.e., that cavity enclosed within the internal chamber) may be substantially sealed by a substantially circular and substantially transverse first diverter plate scalingly coupled proximate the first internal chamber end. The first diverter plate may be substantially planar or may (preferably) be substantially conical in at least a central portion for the purpose of smoothly redirecting (diverting) a substantially axial flow of heating gas to a more peripherally located gas guide.
For embodiments of the invention having provision for dilution of the heating gas stream with cooling fluid (to limit its maximum temperature as it enters the gas guide), the cooling fluid may optionally be added to the heating gas stream by injecting the fluid under pressure through one or more perforations in the first diverter plate and thus into the heating gas stream flowing past the plate on its way to the gas guide. Where dilution of the heating gas with a cooling fluid takes place outside of the screw shaft or at a (diluting) burner, cooling fluid injection at the first diverter plate may not be necessary and the first diverter plate may then have no perforations.
If cooling fluid is moved through the central cavity, the cavity itself may contain a duct for carrying the cooling fluid directly to the first diverter plate to be metered into a high-temperature incoming heating gas stream. The cavity itself may act as a duct in certain embodiments, without the requirement of any additional duct within it. If at least a portion of the cavity is to serve as a duct for cooling fluid, the end of that portion serving as a duct which is closest to the screw shaft second end would preferably be scaled against the entry of any fluid but cooling fluid by a second diverter plate, the plate generally being perforated to admit cooling fluid from a duct with which the plate scalingly communicates. In the case where a cooling fluid duct scalingly communicates (as through a rotary joint seal) directly with the central cavity, the function of the second diverter plate, including any allowance for recirculation of exiting heating gas into the cooling fluid stream, would then be performed by the directly-communicating duct.
An example of the second divertor plate function would be the diversion of fluids other than ambient (outside) air from a duct, e.g., keeping heating gas exiting the gas guide from entering the duct. In that case, only outside air would enter the inner cavity for eventual injection into the incoming heating gas stream. Note, however, that at least a portion of the cooling fluid may in certain embodiments comprise heating gas which is entrained in a cooling air flow as the heating gas exits the gas guide. Such a recirculation of a portion of the heating gas as part of the cooling fluid stream could conserve energy previously added to and still carried by the recirculating heating gas, but in preferred embodiments described herein would require venting of at least a portion of the exiting heating gas. Such venting would allow for addition of a new stream of higher temperature heating gas to the recirculating (cooling and diluting) gas flow before the combined recirculated and new heating gas flows enter the gas guide.
Relatively smaller diameter screw shafts may differ from the larger double-wall embodiments in that they may contain no diverter plates but comprise instead a single screw shaft wall wherein a gas guide for heating gas occupies substantially the the entire space within the screw shaft wall and between the first and second bearing areas (which are firmly coupled to the screw shaft wall at the respective rust and second screw shaft wall ends). Firm coupling is achieved by, e.g., welding, riveting, or bolting the firmly coupled structures either directly together or to one or more intermediate structures which are themselves firmly coupled.
Heating gas for either single-wall or double-wall screw shafts may comprise, e.g., exhaust gas from a propane, natural gas or fuel oil burner. Because heating gas loses heat as it flows through a gas guide from the first end to the second end of a screw shaft, the screw shaft first end is generally at a higher temperature than the second end. Thus a thermal gradient is established along the screw shaft longitudinal axis. Heat transfer from the heating gas to various portions of the screw shaft wall may be optimized by controlling the heating gas temperature proximate the screw shaft first end (e.g., by controlled addition of cooling/diluting fluid, preferably comprising air), by modulating the heating gas flow rate, and by altering the gas guide design to obtain a desired (predetermined) pattern of heating gas velocities and turbulances within the gas guide and adjacent to the screw shaft wall. Additionally, thermal conductivities of structures comprising the gas guide may be modified to alter both the rate and distribution of heat transfer from heating gas to the screw shaft wall to optimize conditions for desorption of volatile or semivolatile components of any semisolid material in contact with flights on the outer surface of the screw shaft.
Heating gas may enter each screw shaft first end at a relatively high temperature (having been preheated by a heat source outside the screw shaft), or the heating gas may be elevated to a high temperature substantially within each screw shaft by a fuel burner assembly substantially centered therein and adjustably coupled thereto. Heating gas entering a screw shaft first end, whether preheated or in the form of separate fuel and oxidizer to feed a fuel burner positioned within the screw shaft, is generally directed axially toward the screw shaft second end until it strikes a gas guide (in single-wall screw shafts) or the substantially circular and substantially transverse first diverter plate (in double-wall screw shafts). A first diverter plate, if present, is substantially centered within and sealingly coupled to the internal chamber wall; the plate is proximate the internal chamber wall first end and positioned substantially transverse to the screw shaft rotational axis. Note that such transverse position of the diverter plate may be indicated by the tendency of the plate in such a position to substantially uniformly redirect to a gas guide a substantially axially directed heating gas stream which enters a double-walled screw shaft proximate its first end. As noted above, cooling and diluting fluid may be added to the heating gas stream by ducting such cooling and diluting fluid through the screw shaft second end and forcing it through one or more (preferably symmetrical) perforations made for this purpose in the substantially circular first diverter plate.
If cooling fluid enters a screw shaft through the second screw shaft end, cooling fluid inlet means are preferably used to substantially prevent mixing of cooling fluid and exiting heating gas as both pass through the second beating area in substantially opposite directions. Cooling fluid inlet means thus comprise a (preferably substantially cylindrical) cooling fluid duct sealingly communicating with the internal chamber central cavity (directly or via a second diverter plate) and preferably being substantially coaxial therewith. The cooling fluid duct is preferably substantially centered in the second bearing area and sealingly communicating (directly or via a portion of the central cavity) with a plurality of perforations in the first diverter plate (i.e., so as to be capable of delivering pressurized cooling fluid through the perforations).
When exiting the gas guide of a screw conveyor desorber proximate a screw shaft second end, heating gas preferably passes through the screw shaft second bearing area before being vented to the atmosphere. Because the heating gas has been substantially shielded by each screw shaft wall from direct contact with contaminated material, vaporized (contaminant) fractions from material in contact with the external flight(s) are substantially absent from the heating gas stream as it leaves each screw shaft. Vaporized contaminants, in contrast, are substantially contained in a contaminant vapor space between each screw shaft outer surface and a conveyor wall which substantially surrounds the screw shaft(s) except for portions proximate the first and second bearing areas. The conveyor wall has an inner surface and an outer surface, at least a portion of the conveyor wall inner surface being spaced an effective distance from at least a portion of the (at least one) substantially helical external flight(s) to facilitate self-cleaning and material transport as described herein. Contaminant vapors may then be drawn from the contaminant vapor space by fans or pumps for further processing and/or decontamination.
In screw conveyors of the present invention, the conveyor wall effectively encloses each screw shaft except for portions of the first and second screw shaft bearing areas of each screw shaft, through which heating gas passes (respectively) into and out of the screw shaft. For applications where contaminant gases are flammable, it is preferable that no air mix with the hot (desorbed) gases within the contaminant vapor space because of the danger of fire or explosion. To substantially preclude air from entering the contaminant vapor space (between the conveyor wall inner surface and each screw shaft outer surface) where such mixing may occur, first and second rotating seals (comprising, e.g., substantially cylindrical metallic bellows, packing material for maintaining sliding contact with a bearing area, and one or more glands for compressing the packing material) may be used between each first and second (rotating) screw shaft bearing area and the (nonrotating) portion of the conveyor wall proximate each of the first and second bearing areas respectively. Where, on the other hand, mixture of air with heated contaminant vapors would not constitute a safety hazard, rotating seals may be eliminated, leaving only closely fitting (but non-contact) portions of the conveyor wall adjacent each bearing area of each screw shaft. Such non-contact conveyor wall portions may substantially restrict but not entirely block the passage of air into the contaminant vapor space under the influence of a negative pressure gradient (maintained by fan or pump) from the ambient atmosphere to the contaminant vapor space.
When acting as a part of a screw conveyor desorber, each screw shaft of the present invention is supported by a screw shaft bearing assembly pair comprising first and second bearing assemblies spaced apart and adjustably coupled to a framework. The first and second bearing assemblies of each bearing assembly pair act at the first and second bearing areas respectively of a screw shaft. Each of the first and second bearing assemblies is adjustably coupled (e.g., bolted, screwed or clamped) to the framework to provide for rotation of the supported screw shaft about the centered longitudinal screw shaft rotational axis while the screw shaft rotational axis is held in a substantially fixed spaced relationship to the conveyor wall to which the framework is substantially firmly coupled. Note that in some embodiments of the present invention, the framework may comprise substantially all or a portion of the conveyor wall itself.
Each screw shaft is associated with rotary drive means firmly coupled to the screw shaft wall, preferably to either or both of the first and second screw shaft bearing areas. Rotary drive means may comprise, e.g., one or more sprockets, pulleys and/or gears. In a screw conveyor, each drive means is drivingly coupled to one or more rotary power sources (as by chain, belt or gear drives), the power source(s) being adjustably coupled to the framework and capable of transmitting torque to each screw shaft. The torque is preferably substantially about the screw shaft rotational axis, and when transmitted through both first and second bearing areas, may not be equally divided between the two areas.
Rotary drive torque tends to cause each screw shaft to rotate about its rotational axis, resulting in relative motion of the screw shaft external flight(s) with respect to the conveyor wall. This flight-wall relative motion taking place at an effective flight-wall distance between at least a portion of each screw shaft flight and the conveyor wall tends to aid in semisolid material mixing and transport in the desorber. In conjunction with other elements of the present invention described herein, the flight-wall relative motion may facilitate self-cleaning of the desorber during screw shaft rotation. The effectiveness of both transport and self-cleaning functions may depend on several parameters (e.g., the height of the screw shaft external flight(s) above each screw shaft outer surface relative to the wall-flight distance from the conveyor wall to the nearest screw shaft flight surface) which are preferably determined empirically.
To maintain an effective wall-flight distance for self-cleaning and material transport, at least a portion of the conveyor wall shape substantially conforms to at least a portion of each screw shaft outer surface and thus to the outer edge of the at least one substantially helical external flight which is firmly coupled to the screw shaft outer surface in question. The conforming wall portion is thereby spaced apart from the screw shaft outer surface a distance which is effective for transporting semisolid material in the manner of a screw conveyor. Thus, the minimum wall-flight distance (i.e., the distance measured from the inner surface of the conveyor wall to the closest portion of a screw shaft flight) is always greater than zero but preferably less than an empirically determined distance which, if exceeded, would substantially impair material transport.
A plurality of hardened bits may optionally be substantially firmly coupled to the external flight(s) outer edge(s) and extend both above and to either side of each flight outer edge, thus increasing the minimum distance from the conveyor wall to the screw shaft outer surface by at least the bit height (i.e., the radial distance from the bit base to the bit outer edge). When the screw shaft is rotated, each bit outer edge (which is substantially parallel to the portion of screw shaft outer surface over which it is positioned) describes a substantially right circular cylindrical pathway in space. The wall of each said spatially described right circular cylinder comprises the longitudinal bit sweep, which locates and defines the longitudinal length of the area which will be swept by that bit adjacent to the conveyor wall.
For optimal conveyor wall cleaning, each said longitudinal bit sweep will abut (adjoin) or slightly overlap the longitudinal bit sweep of the bit which just precedes and/or follows the bit in question on the screw shaft flight(s). In the case where a plurality of hardened bits is substantially evenly spaced along at least one substantially helical external flight outer edge and where the corresponding bit sweeps combine to form a substantially contiguous composite sweep, the composite sweep will preferably be equal in length to the effective longitudinal flight length. The hardened bits can thus automatically prevent adherent material buildup on the conveyor wall from interferring with screw shaft rotation for at least a portion of the screw shaft length, preferably the entire effective longitudinal flight length of each screw shaft.
Screw shaft rotation may also optionally activate scraping action on the flights and/or screw shaft outer surfaces of two or more adjacent counter-rotating screw shafts having opposite-handed external flights, each screw shaft having one or more external flights which mesh with (i.e., overlap) one or more corresponding external flights on the adjacent screw shaft. Such meshing allows portions of flights on adjacent screw shafts to interleave without interference during simultaneous rotation of the screw shafts. Additionally, one or more breaker devices coupled to the framework (where coupling to the framework may be through a portion of the conveyor wall) preferably maintain at least intermittent slidingly contact with at least a portion of the external flight(s) and/or the screw shaft outer surface of each screw shaft to automatically keep flight surfaces and/or the screw shaft outer surface of each screw shaft substantially free of adherent deposits while simultaneously aiding in the mixing of transported material to enhance heat transfer and desorption. Breaker device coupling to the framework through the conveyor wall is preferably sliding, springing, and/or sliding and springing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A schematically illustrates a longitudinal partial cross-sectional view of a double-wall indirect-heating desorber with cooling fluid introduced at a (diluting) burner within the screw shaft.
FIG. 1B schematically illustrates a longitudinal partial cross-sectional view of a double-wall indirect-heating desorber with cooling fluid inlet means introducing cooling fluid through the screw shaft second end to mix with heating gas heated outside of the desorber.
FIG. 1C schematically illustrates a longitudinal partial cross-sectional view of a double-wall indirect-heating desorber with cooling fluid inlet means introducing cooling fluid through the screw shaft second end to mix with heating gas from a high-temperature burner within the screw shaft.
FIG. 1D schematically illustrates a longitudinal partial cross-sectional view of a single-wall indirect-heating desorber screw shaft.
FIG. 1E schematically illustrates a cutaway view of portions of the screw shafts and conveyor wall of a twin-screw indirect-heating desorber comprising two single-wall screw shafts.
FIG. 2 schematically illustrates a cutaway view of gas guides on a double-walled screw conveyor screw shaft.
FIG. 3A schematically illustrates a plurality of hardened bits on adjacent flights.
FIG. 3B schematically illustrates a side elevation of a hardened bit.
FIG. 3C schematically illustrates a cross-section of a hardened bit.
FIG. 4A schematically illustrates isometric views of a plurality of breaker devices slidingly coupled to the conveyor wall of a screw conveyor desorber.
FIG. 4B schematically illustrates an enlarged view of a single breaker device as in FIG. 4A, with adjacent portions of a screw shaft and external flight(s).
FIG. 4C schematically illustrates an enlarged view of the cable guide associated with the breaker devices as in FIG. 4A.
FIG. 4D schematically illustrates an isometric view of a plurality of breaker devices springingly coupled to the conveyor wall.
FIG. 4E schematically illustrates cutaway view of a plurality of breaker devices slidingly and springingly coupled to the conveyor wall.
FIG. 4F schematically illustrates an end elevation of a plurality of breaker devices slidingly and springingly coupled to a conveyor wall, with a cross-sectional view of an adjacent screw shaft (including flight surfaces).
DETAILED DESCRIPTION
Various preferred embodiments of the present invention may include parts which, while in analogous positions, differ in certain structural and/or functional respects. Throughout this description, such analogous parts are identified by reference numbers on the drawing(s) in which the parts are illustrated most dearly, the various alternative embodiments being identified in each case by the reference number unprimed, the primed reference number ('), the double-primed reference number ("), etc. Note that while the drawings and descriptions herein provide representative schematic illustrations and explications of several preferred embodiments of the present invention, those skilled in the art will recognize that the invention is not intended to be limited to the specific forms set forth herein, but on the contrary is intended to include such alternatives, modifications and equivalents as can reasonably be included within the spirit and scope of the invention as defined by the appended claims.
For example, the preferred embodiments of desorbers 99, 99', 99" of the present invention as shown in FIGS. 1A, 1B and 1C respectively illustrate different approaches to addition of cooling fluid to a heating gas stream. In FIG. 1A, fuel, air, and cooling fluid enter a diluting burner 29 centered within the first screw shaft bearing area 11 proximate screw shaft first end 8 to produce a heating gas stream 21 at a suitable temperature for entry to the gas guide 10 without the need for additional dilution with cooling fluid. Thus, first diverter plate 20 in FIG. 1A requires no perforations to allow passage of cooling fluid, whereas first diverter plate 20' (as in FIGS. 1B and 1C) has one or more perforations 65 (preferably in a substantially symmetrical pattern) to allow passage of cooling fluid which enters the screw shaft second end 19 through cooling fluid inlet means (including cooling fluid duct 18 and second diverter plate 50' in FIGS. 1B and 1C) and eventually mixes with heating gas stream 21. A perforated first diverter plate 20' is thus particularly useful for accommodating high-temperature fuel burners 29' positioned proximate screw shaft first end 8 and producing a relatively high-temperature heating gas stream 21', as in FIG. 1C. Note that a high-temperature heating gas stream 21' produced from a source outside a screw shaft as in FIG. 1B will also require dilution with a cooling fluid proximate perforated first diverter plate 20' before entering gas guide 10.
Alternative screw shaft configurations having both first diverter plate 20 and second diverter plate 50 non-perforated (as in FIG. 1A), or no diverter plate at all (as in the single-wall screw shafts illustrated in FIGS. 1D and 1E), require use of heating gas in that screw shaft which has been preheated to an effective temperature for desorption but not above a maximum acceptable temperature. Excessively high heating gas temperatures are avoided to prevent screw shaft overheating and subsequent undesired pyrolysis or phase change of portions of the transported material (including contaminants), and/or to prevent fouling of screw shaft and conveyor wall surfaces with adherent deposits. Note that the objective of all dilutional cooling of the heating gas is to ensure that the heating gas maximum temperature on entry to a gas guide 10 is low enough to avoid such overheating of any portion of the screw shaft outer surface 3 or the external flight(s) 14 thereon during passage of the heating gas through the gas guide 10.
In preferred embodiments of desorbers of the present invention 99, 99', 99", the uppermost portion of the conveyor wall 34 encloses a vapor dome area 30 where heated contaminant gases may collect prior to being drawn off for further processing and/or decontamination. Portions of the conveyor wall 34 around the vapor dome area 30 have one or more access ports 55 for removal of contaminant vapors and/or addition of contaminated material to the desorber. At least one material outlet 56 is also provided in the conveyor wall 34, typically spaced apart from and lower than the material inlet(s) 55.
In preferred embodiments of the present invention, first and second screw shaft beating areas 11,12 preferably comprise double-wall cylindrical portions 36 which may be cooled by forced (active) or passive circulation of cooling fluid (preferably comprising air) through the double-walled cylindrical portions 36. This cooling provides thermal protection of, e.g., first and second screw shaft bearing assemblies 60,61, rotary seals 9, rotary drive means 62, and rotary power source 13 from relatively high screw shaft temperatures. Such cooling of screw shaft bearing areas 11,12 may be accomplished on either double-walled screw shafts 1 or single-walled screw shafts 1', either embodiment being suitable for incorporation of double-walled cylindrical portions in either first or second bearing areas 11,12 respectively or both.
Material is transported in screw conveyors 99,99',99" of the present invention in part by the action of external screw threads or flights 14, which act as inclined planes to convert rotary motion of the screw shaft 1,1' to movement of the material in a direction substantially parallel to the longitudinal (rotational) axis of the screw. Material transport (throughput) capacity may be increased or decreased for a given desorber by tilting (pivoting) the centered longitudinal (rotational) axis through a tilt angle so that the first and second ends of a screw shaft are at different elevations with respect to a horizontal plane. In preferred embodiments, such tilting of the centered longitudinal axis may be accomplished by rotating the framework 26 about a pivot 40 mounted on the framework.
Transported material is maintained in sliding contact with at least a portion of the flight(s) 14 by a curved (substantially conforming) portion of the conveyor wall 34. The conveyor wall 34 is spaced proximate to but apart from the flights 14 along at least a portion of the length and circumference of screw shaft 1,1'. Transported material in sliding contact with the flight(s) 14 tends to be transported substantially from points proximate the second end 19 (i.e., the material input end) of the screw shaft 1,1' to points more proximate the first end 8 (i.e., the material output end). In the case of a constant-diameter screw shaft 1,1', at least a portion of the conveyor wall 34 is commonly in the form of a right circular cylinder (or longitudinal section thereof) which is substantially coaxial with the screw shaft's centered longitudinal rotational axis and thus surrounds at least a part of the screw shaft 1,1' at one or more fixed distances. A variant of this configuration is a trough having outwardly-sloping sides and a bottom substantially in the shape of a longitudinal hemi-section of a right circular cylinder. Optimal values for the height X of flight outer edge 16 above screw shaft wall outer surface 3, the pitch Y, the bit height H and the flight-wall spacing distance Z (greater than zero) are chosen based in part on the nature of the material to be transported, including its particle or granule size range, its resistance to flow in the desorber, any tilt present in the desorber longitudinal axis, and the desired throughput capacity of the desorber.
In general, screw conveyors with external flights require relatively dose (but not zero) flight-wall spacing for relatively fine soils and sludge. If even small amounts of adherent compacted material are allowed to accumulate on flights, on inter-flight screw shaft outer surfaces, or on the conveyor wall, effective flight-wall spacing may reach zero and the screw may jam. Even without screw jamming, material accumulations on inter-flight surfaces may substantially decrease material throughput capacity by reducing the amount of material in effective sliding contact with a flight. Further, as flight-wall spacing approaches zero, torque requirements for conveyor operation may rise abruptly, resulting in excessive wear of rotary drive components, possible shaft breakage, and/or screw shaft beating assembly damage.
Besides maintaining a desired flight-wall spacing, desorbers of the present invention obviate the adverse effects of adherent deposits on inter-flight screw surfaces. Automatic removal of this material maintains the design throughput capacity for a conveyor as well as improving heat transfer efficiency from the heating gas through the screw shaft outer surface to the material being transported. Optional features, including control of rotary drive parameters (e.g., screw rotational speed and/or rotary drive torque), as well as modification of heat source parameters (e.g., fuel flow rate, burner heat output, fuel/air ratio, flame geometry and/or heat distribution patterns), may be employed in open or closed loop control systems to further increase desorber efficiency and reliability. In certain embodiments of the invention, a relatively high heat-output fuel burner may be used in conjunction with automatic closed-loop adjustment of heat source parameters and rotary drive parameters to allow adjustment of overall desorber operation to accommodate different types of contaminated material. Contaminated-material parameters including, for example, specific heat, material flow characteristics, contaminants present, moisture content and heat stability may be considered in making adjustments to conveyor heat source and rotary drive parameters using closed-loop control system methods.
In desorbers of the present invention, provision is made for automatic removal of caked, coked, fused, compacted, compressed or otherwise adherent masses of material on the screw and/or conveyor wall surfaces during screw rotation. Preferred embodiments provide for material removal from at least a portion of the screw shaft outer surface only, or from conveyor wall surfaces only, or from both screw and internal conveyor wall surfaces. Choice of a particular embodiment for a given material transport application depends on consideration of factors including the composition and consistency of material transported, the speed of screw rotation, and the temperatures of the transported material and various surfaces within the screw conveyor.
Because of the variety of granular or particulate materials that may require decontamination, and the differing tendencies of these materials to form adherent deposits, desorbers of the present invention may be adjusted for optimal performance with any given input material. Adjustments may be performed manually, or a desorber may incorporate closed-loop screw rotary drive controls in conjunction with closed-loop control of heat source parameters to effectively reduce the rate of adherent deposit buildup. Desorbers embodying the latter features would typically be capable of operation at sustained high screw temperatures and relatively high throughput rates by adjustment of rotary drive and heat source parameters to an optimal set for the material(s) presented for decontamination. Optimization criteria may include, for example, avoidance of overheating in any portion of the desorber, reduction of contamination to residual levels desired for particular contaminants, reduction of the total time required for a particular decontamination task, or minimization of fuel consumption. Algorithms for each parameter optimization program generally incorporate empirically-derived data for the particular desorber to which they are applied. Modification of the algorithms during desorber operation may be employed to make the desorber automatically adaptive to changes in parameters of the contaminated material.
Preferred embodiments of the invention may also include provision to apply predetermined (and optionally time-varying) forces to maintain one or more breaker devices in at least intermittent sliding contact (at their hardened tips) with at least a portion of the flight(s) and/or screw shaft outer surface during screw shaft rotation. Breaker devices preferably comprise hardened tips or contact surfaces of, e.g., tungsten carbide or other hard, tough material, and will preferably be firmly coupled to the conveyor wall and/or framework. Coupling may be passive (e.g., through one or more springs and/or sliding couplings) or active (e.g., through a hydraulic or pneumatic cylinder), and may be associated with passive or active damping of bit motion. Contact with desired inter-flight portions of the screw shaft outer surface and/or with a flight by a single breaker device may be maintained during screw rotation if the device is moved longitudinally in a coordinated manner so as to avoid interference with advancing flight surfaces.
For a breaker device coupled to the conveyor wall and/or framework, adaptation to maintain substantial sliding contact with the screw implies that the breaker device has a contact area (tip) which may be hardened, polished, reinforced and/or otherwise prepared to withstand sliding contact with the flight(s), the screw shaft outer surface, and any adherent deposits thereon. To avoid damage from interference with flights, a breaker device must be capable of at least limited motion in a direction substantially parallel to the screw shaft's centered longitudinal axis (i.e., longitudinal motion). Such longitudinal motion would allow the breaker device, for example, to maintain at least intermittent sliding contact with at least a portion of a flight and/or screw shaft outer surface even as the screw shaft is turning. In preferred embodiments, a plurality of breaker devices may be swept along passively by the advancing face of a flight or they may be actively advanced synchronously with the flight (i.e., away from the input end of the screw and toward the output end).
Passive longitudinal breaker device motion along at least a portion of the screw length may be accommodated by a coupling comprising a wall-coupled and/or framework-coupled spring; in certain embodiments, functions of the breaker device and the wall-coupled and/or framework-coupled spring are combined in a single spring. Such a breaker device is schematically illustrated in FIG. 4D, in which a plurality of springs 43 are coupled to the framework 26 and conveyor wall 34. As screw 1' rotates clockwise (indicated by the arrow adjacent second end 19), flights 14, firmly coupled to screw shaft outer surface 3 at flight base edge 15 tend to move springs 43 in the direction of the arrow on the upper surface of screw shaft 1'. Springs 43 are preferably in at least intermittent sliding contact with both screw shaft outer surface 3 and flights 14 as screw shaft 1' rotates, but springs 43 are eventually moved sufficiently longitudinally by sliding contact with flights 14 to cause flight outer edges 16 to lift springs 43 away from sliding contact with screw shaft outer surface 3. Continued screw shaft rotation at that point causes springs 43 to slide over a flight outer edge 16 and return under spring force back toward second end 19 to reestablish at least intermittent sliding contact with screw shaft outer surface 3. The sliding and returning motions of springs 43 during rotation of screw shaft 1' due to contact with flights 14 tends to automatically dislodge accumulated material from both flights 14 and screw shaft outer surface 3. If the amount of longitudinal spring motion that a single breaker device spring 43 can accommodate is insufficient to allow sliding contact with desired portions of the screw, a plurality of wall-coupled and/or framework-coupled spring breaker devices 43 may be spaced along the length of screw shaft 1', as schematically illustrated in FIG. 4D.
Longitudinal breaker device motion along at least a desired portion of the screw shaft length may also be accomplished as schematically illustrated in FIGS. 4A, 4B and 4C by a sliding coupling of breaker devices 70,70' to the conveyor wall 34 via guide rods 75,75', hold-down rods 77,77', and lifting rods 76,76' which rods are themselves firmly coupled to conveyor wall 34. Breaker devices 70,70' are flexibly coupled by cable 74 which travels in cable guide 72, cable 74 being substantially non-stretching and cable guide 72 being firmly coupled to conveyor wall 34.
An example of the operation of this slidingly coupled breaker device is schematically illustrated in FIG. 4A by reference to breaker devices 70,70' in initial positions A1,A2 respectively. In position A1, breaker device 70 is held in at least intermittent sliding contact with screw shaft outer surface 3 by hold-down rod 77. As screw shaft 1' then rotates clockwise as shown by the arrow adjacent second end 19, flights 14 (which are firmly coupled to screw shaft outer surface 3 at flight base edge 15) tend to push breaker device 70 away from second end 19 in the direction of the arrow adjacent breaker device 70 at position A1 (while breaker device 70 maintains at least intermittent sliding contact with flights 14 and screw shaft outer surface 3). Such movement of breaker device 70 tends remove deposits from flights 14 and screw shaft outer surface 3 and to place cable 74 in tension, which in turn tends to pull breaker device 70' (sliding on guide rod 75') from its initial position A2 toward second end 19. Note that as breaker device 70' moves toward second end 19, it slides over hold-down rod 77' (analogous to the subsequent returning position of breaker device 70 at position C1) and so is not in contact with flights 14 or screw shaft surface 3.
As breaker device 70 slides on guide rod 75 toward the end of its travel under hold-down rod 77, breaker device 70 tends to be lifted away from contact with flights 14 and screw shaft outer surface 3 by lifting rod 76. When breaker device 70 has been lifted dear of outer edge 16 of flight 14 by lifting rod 76, it is also lifted above hold-down rod 77 (see position B1), and simultaneously breaker device 70' reaches the end of its travel toward second end 19 and is no longer sliding over hold-down rod 77'. Thus, breaker device 70' is free to rotate on guide rod 75' into at least intermittent sliding contact with flights 14 and screw shaft outer surface 3 and, with continued clockwise rotation of screw shaft 1', tends to be moved by flights 14 in a longitudinal direction away from second end 19, contact with flights 14 being maintained because breaker device 70' is then held in at least intermittent sliding contact with screw shaft outer surface 3 by hold-down rod 77'. Thus, breaker device 70' then tends to exert tension on cable 74 which tends to return breaker device 70 (now prevented from contact with flights 14 or screw shaft outer surface 3 by sliding above hold-down rod 77) through position C1 and continuing back to the starting position considered in this illustrative example.
Another means of achieving longitudinal breaker device motion for a breaker device which in at least intermittent sliding contact with flights 14 and screw shaft outer surface 3 is schematically illustrated in FIGS. 4E and 4F. The breaker devices in this example are slidingly and springly coupled to conveyor wall 34. A plurality of breaker devices 42 is firmly coupled to base bar 44 which in turn is slidingly coupled to framework 26 (or alternatively through conveyor wall 34 to framework 26) through bearing 45. Spring 46 applies either spring tension or compression longitudinally in conjunction with spring torque to base bar 44 so that breaker devices 42 tend to be springingly rotated into at least intermittent sliding contact with screw shaft outer surface 3, while springingly resisting longitudinal movement of breaker devices 42 in response to sliding contact with flights 14 during clockwise rotation of screw shaft 1' (as indicated by the arrow adjacent second end 19). As flights 14 move and tend to exert ever greater force on breaker devices 42, breaker devices 42 tend to be rotated out of contact with flights 14 while spring 46 is either compressed or stretched, depending on the orientation of spring 46 with respect to the direction of rotation of screw shaft 1'. Progressive stretching or compression of spring 46 tends to increase the force of contact between breaker devices 42 and flights 14. The increasing contact force then tends to move the ball tips 35 of breaker devices 42 from positions relatively near the flight 14 base edge 15 toward the flight 14 outer edge 16, finally resulting in substantial loss of contact between breaker devices 42 and flight outer edge 16 as breaker devices 42 jump or skip over one surface of flight 14 to a corresponding position on a proximate flight 14 surface. During the skipping or jumping movement of breaker devices 42, spring 46 tends to return to a more neutral position (i.e., to a position where less longitudinal spring force is exerted on base bar 44).
Thus, depending on the orientation of base bar 44 and spring 46 with respect to the direction of rotation of screw shaft 1', breaker devices may be positioned to preferably be in at least intermittent sliding contact with flight(s) 14. By appropriate choice of positions and numbers of breaker devices 42, virtually any portion of flights 14 may be substantially cleaned of adherent material as a result of contact with breaker devices 42.
Preferred embodiments of the present invention may include bits 23 of hardened, tough material substantially firmly coupled to a flight and/or the screw shaft surface so as to extend above the flight a distance (i.e., the bit-height distance H) greater than zero but less than the flight-wall distance Z (the former distance illustrated in FIG. 3B and the latter distance illustrated in FIG. 1E). Note that bits 23 as illustrated schematically in FIGS. 3B and 3C may comprise a hardened surface 24 which may extend over at least an adjacent portion of external flight(s) 14. Such a hardened surface 24 may be achieved, e.g., through sputtering, welding and/or heat treating bits 23 and/or external flight(s) 14. Bits 23 in certain preferred embodiments are substantially similar in size and spaced substantially evenly along a flight so that a plurality of bits of width W and an angular orientation angle Θ with respect to a perpendicular to the longitudinal (rotational) axis of the screw shaft 1,1' will together sweep a substantially uninterrupted portion of space in the shape of a right circular cylinder proximate conveyor wall 34 on rotation of the screw shaft 1,1'. This substantially uninterrupted spatial sweep will occur when the effective longitudinal bit sweep W' for each bit inside the end bits of the plurality abuts (adjoins) or slightly overlaps the effective longitudinal bit sweep of the bits which just precede and follow the bit in question on the screw shaft flight(s).
As illustrated in FIGS. 3A, 3B and 3C, each bit outer edge 25 is preferably substantially parallel to the portion of screw shaft outer surface 3 over which it is positioned, thus allowing bit outer edge 25 to describe the desired substantially fight circular cylindrical pathway in space on rotation of screw shaft 1,1'. The wall of each said spatially described right circular cylinder comprises the longitudinal bit sweeps of all bits 23 on the screw shaft 1,1' in question.
For optimal conveyor wall cleaning in at least a local portion of a screw shaft 1,1', each bit's longitudinal bit sweep will be substantially equal to the longitudinal bit sweep of each of the other bits 23 which comprise the plurality of bits on a given screw shaft 1,1' portion. For example, six bits 23, each having an effective longitudinal bit sweep of about one-inch may be substantially evenly spaced (i.e., about every 60 degrees) along a substantially helical flight 14 having a six-inch pitch Y. This bit spacing will ensure that the effective longitudinal bit sweeps for the six bits will together form a substantially contiguous composite sweep of total effective longitudinal length of about six inches. In preferred embodiments, the substantially contiguous composite sweep length is substantially equal in length to the effective longitudinal fight length (i.e., the longitudinal length of that portion of the screw shaft outer surface 3 to which flight(s) 14 are firmly coupled).
Bit widths W may preferably lie within the range of about 0.5 to about 6 inches, but the effective longitudinal bit sweep W' may exceed bit width W if bits 23 are positioned as described above at an angle Θ to a plane perpendicular to the rotational axis of screw shaft 1,1'. In determining the effect of such angular positioning of bits 23 on their effective longitudinal bit sweep, the shape of bit outer edge 25 must be considered, the optimal bit outer edge 25 shape having been empirically defined.
In embodiments of the present invention wherein the mechanical properties (e.g., hardness, friability) of adherent deposits may vary significantly from one end of screw shaft 1,1' to the other, use of non-uniform bit widths and/or inter-bit spacing may be desired to aid in equalizing reaction torque arising from different longitudinal portions of the screw shaft 1,1' (resulting from movement of contaminated material during screw shaft rotation). Additionally, bits 23 are preferably coupled to flight(s) 14 so as to allow relatively easy repair/replacement. Regardless of the spacing chose, in preferred embodiments sufficient bits 23 will be spaced along one or more flights to ensure that substantially all adherent deposits on the conveyor wall which could interfere with screw shaft rotation are effectively scraped by at least one bit, thereby substantially preventing screw shaft jamming due to contact of one or more flights with adherent deposits.
On portions of the conveyor wall 34 having such adherent deposits, a plurality of substantially equally spaced bits 23 firmly coupled to a screw shaft 1,1' may periodically remove chunks of deposited material or scrape the surface of deposited material to leave an underlying layer. In the latter case, the bits will effectively shape, and maintain an intermittent sliding contact with, a new proximate conveyor wall surface comprising adherent deposits. The new surface will substantially approximate the surface of the above substantially contiguous composite sweep in space, the surface being separated from the flights by a distance substantially equal to the (preferably substantially uniform) bit height distance H.
Choice of the optimal dimensions and spacing for bits 23 is based on consideration of parameters including (but not limited to) bit hardness and resistance to fracture, screw diameter and preferred rotational speed, flight size and strength, consistency of any adherent deposits and the preferred rotational torque for the screw shaft. Given a set of parameters including one or more of those above, a preferred range for bit effective longitudinal bit sweeps may be specified. For example, an increase in bit sweep will reduce the number of bits needed for scraping a given longitudinal length of conveyor wall, but wider bits exert greater individual forces on a flight to which they are firmly coupled. Further, frictional force for a single bit on the conveyor wall may significantly differ from the sum of frictional forces for two or more bits having a contiguous composite sweep length substantially equal to the effective longitudinal bit sweep of the single bit 23. Hence, preferred bit width W, as well as optimal bit height H are preferably determined empirically.
Bits 23 may be firmly coupled to flight(s) 14 so as to be substantially coplanar with an adjacent portion of flight 14 as shown in FIG. 3A. Non-coplanar bits (illustrated as 23' in FIG. 3A) may also be employed, but consideration must be given to possible interference with the intended function of any breaker devices used in conjunction with non-coplanar bits 23'.
Methods of providing thermal protection of screw shaft bearing areas in certain embodiments of the present invention comprise provision for active or passive circulation of cooling fluid within double-walled portions of the respective screw shaft bearing areas. In preferred embodiments, each screw shaft bearing area may comprise a plurality of cooling fluid inlets and a plurality of cooling fluid outlets through which cooling fluid (e.g., air, water or fuel) is directed to provide one or more heat sinks for absorbing thermal energy before said energy reaches the bearing assemblies and/or rotary drive components.
Because such absorbed heat is carried away by the cooling fluid, rotary drive components (e.g., bearing assemblies, gears, chains and motors) located within bearing areas would be exposed to a reduced flow of thermal energy from the heated portion of the screw shaft. If the cooling fluid is air and one or more fuel burners act as a heat source, at least a portion of the air which is preheated by passage through double-walled portions of which the bearing areas are comprised may thereafter be directed to the burner(s) to increase the thermal efficiency of the burner(s). Thus, double-walled portions of a screw shaft 1,1' may comprise an air preheater. If desired for cold weather operation, double-walled portions of a screw shaft 1,1' proximate one or both bearing areas may additionally or alternatively comprise a fuel preheater wherein at least a portion of the fuel supply for a desorber burner may be preheated (again, to increase the thermal efficiency of the burner(s)). Certain embodiments of the invention may therefore Comprise either an air preheater or a fuel preheater or both.
Referring to FIGS. 1A, 1B, 1C, 2, and 4F, a double-wall screw shaft 1 of the present invention is seen to comprise a screw shaft wall 2, having a longitudinal length L, an inner surface 4, an outer surface 3, a first end 8, and a second end 19, said screw shaft wall 2 being substantially symmetrical about a substantially centered longitudinal rotational axis extending through said screw shaft wall first and second ends, 8,19 respectively. A double-wall screw shaft 1 also comprises an internal chamber wall 5, having an inner surface 6, an outer surface 7, a first end 27, and a second end 28, said internal chamber wall 5 being substantially symmetrical about a substantially centered longitudinal rotational axis extending through said internal chamber wall first and second ends 27,28 respectively, said internal chamber wall rotational axis being substantially coaxial with said screw shaft wall rotational axis, at least a portion of said internal chamber wall outer surface 7 being contained within, spaced apart from and overlapped by at least a portion of said screw shaft wall inner surface 4 to form a double wall.
A double-wall screw shaft 1 also comprises a gas guide 10, disposed between and firmly coupling said screw shaft wall inner surface 4 and said internal chamber wall outer surface 7, for coupling and spacing apart at least a portion of said internal chamber wall 5 and said screw shaft wall 2 and for guiding heating gas along a substantially predetermined path between said internal chamber wall and said screw shaft wall to facilitate heat transfer from heating gas to said screw shaft wall 2.
A double-wall screw shaft 1 further comprises at least one substantially helical external flight 14, having a base edge 15, an outer edge 16, and at least one local external flight pitch Y, said base edge 15 being firmly coupled to said screw shaft wall outer surface 3 and extending over an effective longitudinal flight length for transporting semisolid material relative to said screw shaft wall outer surface 3 during screw shaft 1 rotation. A first diverter plate 20,20' is firmly coupled to said internal chamber wall 5 proximate said internal chamber wall first end 27 substantially transverse to said internal chamber rotational axis for directing heating gas to said gas guide 10. A first screw shaft bearing area 11 is firmly coupled to said screw shaft wall 2 adjacent said screw shaft wall first end 8, and a second screw shaft bearing area 12 is firmly coupled to said screw shaft wall 2 adjacent said screw shaft wall second end 19. Finally, at least one rotary drive means 62 is firmly coupled to said screw shaft wall 2.
The double-wall screw shaft described above may additionally comprise a second diverter plate 50,50' firmly coupled to said internal chamber wall 5 proximate said internal chamber wall second end 28 and substantially transverse to said internal chamber rotational axis for facilitating, in conjunction with said first diverter plate 20,20', smooth flow of heating gas through the screw shaft 1. In certain embodiments, a rotary drive means 62 is coupled to said screw shaft wall proximate said screw shaft first end. The at least one substantially helical external flight 14 may comprise a single substantially helical external flight having a single substantially constant local external flight pitch Y, but the external flight may also have a single substantially continuously varying local external flight pitch or at least two discrete local external flight pitches.
In certain preferred embodiments of double-walled screw shaft 1 the at least one substantially helical external flight outer edge 16 comprises a plurality of hardened bits 23,23', each said hardened bit 23,23' having an effective longitudinal bit sweep and a bit height. Each of the plurality of hardened bits 23,23' is preferably substantially evenly spaced along said at least one substantially helical external flight outer edge 16, and said plurality of longitudinal bit sweeps combine to form a substantially contiguous composite sweep substantially equal in length to said effective longitudinal flight length.
A preferred embodiment of double-walled screw shaft 1 may have a screw shaft wall 2 about six feet in diameter with a length about twenty-four feet. In this case, the at least one substantially helical external flight 14 has an outer edge 16 extending above said screw shaft wall outer surface 3 a distance X between about one and about six inches, preferably about two and five-eights inches. Firmly coupled to outer edge 16 is a plurality of evenly spaced bits 23,23' wherein each said bit height is between about one-quarter and about two inches, preferably about one inch. The at least one substantially helical external flight 14 has a local external flight pitch of about four inches for a portion extending about four feet from said screw shaft wall first end, a local external flight pitch of about five inches for a portion extending between about four feet and about twelve feet from said screw shaft wall first end, and a local external flight pitch of about six inches for a portion extending between about twelve feet and about twenty-four feet from said screw shaft wall first end.
The gas guide 10 in preferred embodiments of double-walled screw shaft 1 comprises at least one (and preferably eight) substantially helical flights 39, each said at least one gas guide flight 39 having at least one local gas guide flight pitch (preferably of about forty-two and one-half inches).
A single-wall screw shaft 1' comprises a screw shaft wall 2, having an inner surface 4, an outer surface 3, a first end 8, and a second end 19, said screw shaft wall 2 being substantially symmetrical about a substantially centered longitudinal rotational axis extending through said screw shaft wall first and second ends. The single-wall screw shaft 1' also comprises a gas guide 10', firmly coupled to said screw shaft wall inner surface 4 for guiding heating gas along a substantially predetermined path comprising at least a portion of said screw shaft wall inner surface 4 to facilitate heat transfer from heating gas to said screw shaft wall 2.
A single-wall screw shaft 1' further comprises at least one substantially helical external flight 14, having a base edge 15, an outer edge 16, and at least one local external flight pitch Y, said base edge 15 being firmly coupled to said screw shaft wall outer surface 2 and extending over an effective longitudinal flight length for transporting semisolid material relative to said screw shaft wall outer surface 3 during screw shaft 1' rotation. The screw shaft 1' also comprises a first screw shaft bearing area 11 firmly coupled to said screw shaft wall 2 adjacent said screw shaft wall first end 8, and a second screw shaft bearing area 12 firmly coupled to said screw shaft wall 2 adjacent said screw shaft wall second end 19, with at least one rotary drive means 62 firmly coupled to said screw shaft wall 2 (preferably proximate said screw shaft first end 8).
As in the case of a double-wall screw shaft 1, a single-wall screw shaft 1' preferably comprises a single substantially helical external flight 14 which may have a single substantially constant local external flight pitch, a substantially continuously varying local external flight pitch, or at least two discrete local external flight pitches. External flight 14 preferably has an outer edge 16 extending above said screw shaft wall outer surface 3 a distance between about one and about six inches in certain preferred embodiments with a plurality of hardened bits as on external flight(s) 14 of a double-wall screw shaft 1.
Analogously to the gas guide 10 of a double-wall screw shaft 1, the gas guide 10' of a single-wall screw shaft 1' comprises at least one substantially helical flight, said at least one gas guide flight having at least one local gas guide flight pitch (preferably a single local gas guide flight pitch).
A screw conveyor 99,99',99" of the present invention comprises a framework 26 and at least one bearing assembly pair, a beating assembly pair comprising a first screw shaft bearing assembly 61 and a second screw shaft beating assembly 61 spaced apart, said bearing assembly pair being adjustably coupled to said framework 26. The screw conveyor 99,99',99" also comprises at least one single-wall and/or double-wall screw shaft 1,1' respectively as described above, each said at least one screw shaft 1,1' being supported within and rotatingly coupled to said framework 26 by a bearing assembly pair, wherein said first screw shaft bearing assembly 60 acts at said first screw shaft bearing area 11 and said second screw shaft bearing assembly 61 acts at said second screw shaft bearing area 12.
A screw conveyor 99,99',99" of the present invention also comprises a conveyor wall 34, said conveyor wall 34 substantially enclosing said at least one screw shaft 1,1' except for portions of said first and second screw shaft beating areas 11,12 respectively, said conveyor wall 34 having an inner surface 49 and an outer surface 48, at least a portion of said conveyor wall inner surface 49 being spaced an effective distance from at least a portion of said at least one substantially helical external flight 14 on each of said at least one screw shafts 1,1' to facilitate conveyance of semisolid material relative to said conveyor wall 34 and said screw shaft 1,1' during rotation of said screw shaft 1,1' with respect to said conveyor wall 34.
Finally a screw conveyor 99,99',99" of the present invention also comprises at least one rotary power source 13 adjustably coupled to said framework 26 and drivingly coupled to each said at least one rotary drive means 62 for rotating each said at least one screw shaft 1,1' with respect to said framework 26.
Preferred embodiments of a screw conveyor 99" may further comprise at least one fuel burner 29', each said fuel burner being adjustably coupled substantially centrally within said first bearing area 11 of one of said at least one screw shaft 1 to produce high-temperature heating gas directed to said first (perforated) diverter plate 20'.
Preferred embodiments of a screw conveyor 99 may further comprise at least one diluting fuel burner 29, each said fuel burner being adjustably coupled substantially centrally within said first bearing area 11 of one of said at least one screw shaft 1 to produce controlled-temperature heating gas directed to said first (non-perforated) diverter plate 20.
A screw conveyor 99,99',99" of the present invention may further comprise at least one breaker device 42,43,70 coupled to said framework 26 and intermittently slidingly contacting at least a portion of said substantially helical external flight 14 and said screw shaft wall outer surface 3 of each said at least one screw shaft 1,1' to facilitate removal of compacted semisolid material from said external flight 14 and said screw shaft wall outer surface 3. The at least one breaker device 70 is slidingly coupled to said framework 26, breaker device 43 is springingly coupled to said framework 26, and breaker device 42 is slidingly and springingly coupled to said framework 26. Breaker device 42 may additionally comprise a (hardened) ball tip 35 to limit contact with external flight 14 and/or screw shaft wall outer surface 3.
Operation of a desorber 99' of the present invention may incorporate a method of limiting the temperature of heating gas entering desorber 99 to a maximum temperature, the method comprising estimating the temperature of the heating gas entering the desorber 99 to obtain a first temperature, and diluting the heating gas entering the desorber 99 with sufficient cooling fluid at a second temperature to form a mixture of heating gas and cooling fluid at a third temperature, said second temperature being less than said first temperature and the maximum temperature, and said third temperature being substantially equal to the maximum temperature. This method preferably includes use of air as a cooling fluid. | Single or multi-screw indirect-heating screw conveyor desorbers having a heating gas guide enclosed by the screw shaft wall (single-wall screw shafts) or located between a screw shaft wall and an internal chamber wall (double-walled screw shafts). Predetermined amounts of cooling and diluting fluid may be added to a heating gas stream to control the maximum temperature thereof. Screw shaft support bearings and rotary drive components may be cooled, and conveyor wall and/or screw shaft surfaces (e.g.. screw flights and interflight surfaces) may be automatically cleaned during screw shaft rotation by hardened bits and/or breaker devices. Cleaning operations may also involve the interaction of two counter-rotating conveyor screw shafts having mutually interleaved and opposite-handed external flights. Sizing and placement of breaker devices and/or hardened bits is determined empirically to be that necessary to effect substantial removal of material accumulations which would otherwise significantly interfere with efficient conveyor operation. Application of the invention allows design and production of desorbers having decreased weight and size and increased efficiency and reliability compared with currently available indirect-heating screw conveyor desorbers having external screw flights. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a divisional application of U.S. patent application Ser. No. 12/796,308 filed Jun. 8, 2010, the entirety of which is incorporated by reference herein.
FIELD OF INVENTION
[0002] The present invention relates to pharmaceutical grade cis-2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine.
BACKGROUND OF INVENTION
[0003] Cis-2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine (C-MSOQ), also known as cevimeline, is a pharmaceutical compound useful for the treatment of diseases of the central nervous system in mammals, particularly for the treatment of diseases due to disturbances of central cholinergic function and autoimmune disease such as Sjogren's syndrome.
[0004] U.S. Pat. No. 4,855,290 describes a process of making the intermediate 3-hydroxy-3-mercaptomethylene quinuclidine using a sodium hydroxide/dichloromethane system and hydrogen sulfide at 40° C. with 33 to 40% yield. Drawbacks of this process include providing the intermediate in very low yields due to the decomposition of the intermediate in the given reaction conditions, side product “diol” formation due to the susceptibility of the epoxide moiety to form diol with the sodium hydroxide solution at the recommended temperature, and the requirement of a continuous stream of hydrogen sulfide gas.
[0005] U.S. Pat. No. 5,571,918 describes the preparation of the intermediate 3-hydroxy-3-mercaptomethylene quinuclidine by a process of passing hydrogen sulfide gas continuously with a special type of catalyst, p-toluene sulfonic anhydride. Drawbacks of this process include an excess use of hydrogen sulfide gas by passing the hydrogen sulfide gas continuously for more than 6 hours and the requirement of an additional catalyst to complete the reaction. The amount of hydrogen sulfide used for the process is quite high −18 grams/per minute flow for 6 hours, therefore for a 13.9 gm batch of product the required quantity of hydrogen sulfide gas is 6.5 kg.
[0006] U.S. Published Patent Application No. 2008/0249312 describes a two way process of making the aforementioned intermediate using thiol-acetic acid, an industrially toxic chemical with a highly unpleasant odor, with a yield of approximately 60 to 70%. This process requires first making the salt and then isolating the salt to obtain the salt of the intermediate, which is then used for the subsequent reaction.
[0007] For the preparation of the cis isomer of cevimeline, U.S. Pat. No. 4,855,290 describes a process employing multiple recrystallization of the racemic 2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine. Drawbacks of this process include lack of scalability due to multiple recrystallization steps and the requirement of enrichment of the cis-isomer from mother liquor involving chromatographic purification and isolation. In addition to unsuitability for commercialization, the resultant yield after several steps of purification is less than 10%.
[0008] U.S. Pat. No. 4,981,858 involves a resolution of enantiomers of cis and trans isomers of 2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine individually by a tartaric acid resolution technique. There is no discussion regarding preparation and purification of the cis isomer from a racemic 2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine.
[0009] U.S. Pat. No. 4,861,886 describes the conversion of pure trans 2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine to the cis isomer under different conditions. However, no method is taught or disclosed for complete conversion of the trans isomer to the cis isomer. None of the techniques describe how to obtain pharmaceutical quality cis-2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine.
[0010] U.S. Pat. No. 5,571,918 describes the conversion of racemic 2-methylspiro(1,3-oxathiolane-5,3′) quinuclidine to the cis isomer using stannic chloride as a catalyst. There is no teaching of any process or technique to obtain the cis isomer with greater than 98.5% purity when analyzed by HPLC.
[0011] Therefore, there is a need for an industrially viable process that achieves better yields of cis-form-2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine and employs less expensive reagents and solvents, resulting in lower production costs. Furthermore, there is further a need for a process which can generate cis-form-2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine of a pharmaceutically acceptable isomeric purity, i.e., at least 99.0% purity or greater, without the need for multiple tedious isolation, purification and/or separation steps.
SUMMARY OF THE INVENTION
[0012] Industrially advantageous methods are provided for making pharmaceutical grade cis-2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine (sometimes referred to herein as C-MSOQ) and pharmaceutically acceptable salts thereof. The disclosed methods provide surprisingly high yields and purity of C-MSOQ, cevimeline hydrochloride and hydrate forms thereof through the control of intermediates using novel solvent systems and reactions.
[0013] In one embodiment the disclosed method provides cis-2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine by isomerizing racemic 2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine to cis-2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine and subsequent purification of the C-MSOQ by salt formation with inexpensive and commercially available material such as sulfuric acid. This salt is purified by a novel purification method which employs an organic solvent/water system and recrystallization with an organic solvent such as acetone.
[0014] In one embodiment, the method involves preparing 3-hydroxy-3-methyl-quinuclidine, isomerizing racemic 2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine (65:35 trans:cis isomer) to initially about 90% cis isomer with a Lewis acid such as titanium tetrachloride and subsequent purification by acid addition salt formation with an inorganic acid such as sulfuric acid. The resulting sulfate salt is further purified with an organic solvent/water acetone medium to produce pharmaceutical-grade cis-2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine wherein the cis isomer purity is greater than or equal to 99.5% by HPLC.
[0015] In another embodiment, a novel simple, single-step method is disclosed in which the intermediate 3-hydroxy-3-mercaptomethylene quinuclidine is prepared from the epoxide of 3-methylene quinuclidine using hydrogen sulfide in molar quantity in a solvent medium of methanol. This method is industrially more acceptable and inexpensive, and achieves much higher yields, compared to prior art processes referenced above. Employing hydrogen sulfide in a molar ratio avoids any excess quantity of hydrogen sulfide. The disclosed processes do not require any catalyst. The reaction time is much shorter than prior art processes, which helps greatly to stabilize the 3-hydroxy-3-mercapto methyl quinuclidine—and reduces plant utilization time and equipment usage.
[0016] In one embodiment, in situ reaction of the 3-hydroxy-3-mercaptomethyl quinuclidine with acetaldehyde and boron trifluride etherate is employed to obtain racemic 2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine. The racemic 2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine is isomerized to cis-2-methylspiro(1,3-oxathiolane 5,3′)quinuclidine using titanium tetrachloride and further purified by salt formation and recrystallisation with concentrated sulfuric acid and an organic solvent to obtain pharmaceutically acceptable quality cis-2-methylspiro(1,3-oxathiolane 5,3′)quinuclidine of >99.5% purity by HPLC.
[0017] These and other aspects of the invention will be apparent to those skilled in the art.
DETAILED DESCRIPTION
[0018] In the following description, for purposes of explanation, specific numbers, materials and configurations are set forth in order to provide a thorough understanding of the invention. It will be apparent, however, to one having ordinary skill in the art that the invention may be practiced without these specific details. In some instances, well-known features may be omitted or simplified so as not to obscure the present invention. Furthermore, reference in the specification to phrases such as “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of phrases such as “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.
[0019] In accordance with one embodiment a method is disclosed for the preparation of the key intermediate 3-hydroxy-3-mercaptomethyl quinuclidine by passing a fixed quantity of hydrogen sulfide gas to the epoxide of 3-methylene quinuclidine in a novel solvent medium of methanol.
[0020] Scheme 1 below shows a method of preparing the epoxide of 3-methylene quinuclidine, which method is known in the art.
[0000]
[0021] As shown in Scheme II below, the epoxide of 3-methylene quinuclidine is dissolved in a medium of dichloromethane/methanol and a fixed quantity of hydrogen sulfide is introduced to the solution for a period of 1 to 3 hours at a temperature range of −10 to 5° C. The gas flow is stopped and the reaction mixture is stirred for another 1 to 3 hours to convert 3-methylene quinuclidine to 3-hydroxy-3-methyl quinuclidine. In a preferred embodiment, as shown in Stage I of Scheme II, the amount of hydrogen sulfide used is either exactly what is required or slightly in excess of the mole ratio, to avoid excessive usage of this toxic gas. Excess hydrogen sulfide may be removed by passing nitrogen gas through the reaction mixture.
[0022] As shown in Stage II below, the resulting thiol derivative is converted in situ to 2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine. The disclosed one-pot conversion of the epoxide of 3-hydroxy-3-mercaptomethyl quinuclidine to 2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine is simple, achieves high yields and is easily scalable, all with inexpensive reagents/chemicals in a short reaction time. Surprisingly, it was found that methanol can be used as a good solvent medium for this reaction. This finding is contrary to the usage of methanol for these type of reactions, as it is well known methanol can compete as a nucleopile with hydrogen sulfide.
[0023] The compound 3-hydroxy-3-mercaptomethylquinuclidine is very unstable. The disclosed methods of preparation allow for the next step without any serious difficulties and result in very high yield of 2-methylspiro(1,3-oxathiolane 5,3′)quinuclidine. Two-way addition of 3-hydroxy 3-methylquinuclidine and boron trifluoride to an acetaldehyde solution at low temperature minimizes impurity formation and maximizes the yield.
[0000]
[0024] Stage I of Scheme III shown below involves the isomerization of the racemic 2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine. Stage II illustrates the purification process to obtain the cis isomer with >99.5% purity by HPLC.
[0025] In a preferred embodiment a mixture of racemic 2-methylspiro (1,3-oxathiolane-5,3′) quinuclidine with an isomer ratio of about 65:35 cis:trans respectively is isomerized initially to 90% cis 2-methylspiro (1,3-oxathiolane5,3′)quinuclidine with the Lewis acid catalyst titanium tetrachloride in an organic solvent such as acetone, dichlororomethane, dimethyl sulfoxide, methyl isobutyl ketone or a mixture thereof. A suitable quantity of titanium tetrachloride preferably, 0.5 to 5 moles, is added to the racemic 2-methylspiro (1,3-oxathiolane-5, 3′)quinuclidine in a solvent system as described above. The reaction mixture is stirred for 1 to 48 hours at a temperature range of −5 to 50° C. After the completion of the isomerization, the reaction mass is worked up to generate the free base of cis-2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine having nearly 90% purity of cis isomer by HPLC.
[0026] The above-generated cis isomer is further converted to greater than or equal to 99.5% cis isomer (HPLC purity) by salt formation with sulfuric acid, purification and finally to hydrochloride salt. A suitable amount of sulfuric acid, preferably 1.0 to 3.0 equivalents relative to the input quantity, is added to the above-described nearly 90% pure cis 2-methylspiro (1,3-oxathiolane-5,3′)quinuclidine base at a temperature range of 0 to 30° C. After addition, the reaction mass is stirred for 2 to 24 hours at a temperature range of 0 to 115° C., preferably 20 to 40° C., and filtered to isolate the sulfate salt. The above prepared salt can be recrystallized in a solvent such as acetone, ethyl methyl ketone, methyl isobutyl ketone or a mixture thereof at different temperature ranges to obtain the desired pharmaceutically acceptable grade cis-2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine having a purity of 99.5% of cis-isomer by HPLC.
[0000]
EXAMPLES
Example I Preparation of 3-Hydroxy 3-Mercapto Methylquinuclidine
[0027] A solution of the epoxide of 3-methylene quinuclidine (100 g, 0.719 moles) in dichloromethane was cooled to a temperature between about 0 to 5° C. The solution was charged with methanol (100 ml). The mass was stirred for 10 to 15 minutes at this temperature range. To this cold solution hydrogen sulfide gas (50 g, 1.4 mol) was passed and after the passing was complete, the reaction was continued at this temperature for 2 to 3 hours, monitored by gas chromatography, whereupon the peak of epoxide of 3-methylene quinuclidine disappeared. After completion of the reaction, a dichloromethane solution of 3-hydroxy 3-mecapto methylquinuclidine in methanol was obtained. This solution was used for the next step.
Example II
[0028] A solution of acetaldehyde (250 ml) in dichloromethane (1000 ml) was cooled to 0 to 5° C. To this solution was charged the 3-hydroxy-3-mecapto methylquinuclidine solution (100 g epoxide equivalent) prepared in Example I. Boron trifluoride etherate (320 ml) was added simultaneously drop wise over 2 to 3 hours. After completion of the addition, the reaction mass was stirred at 20 to 25° C. for an additional 3 hours. The reaction mass was cooled to 0 to 5° C. A solution of sodium hydroxide (150 g dissolved in 150 ml water) was charged to the solution and the pH of the mixture was adjusted to 12 to 14. The layers were separated. The dichloromethane layer was washed with 5% sulfuric acid solution (500 ml). The product was extracted again in di-isoproyl ether with basification of the aqueous layer to pH 10 to 12. The organic layer containing the product was separated and the base converted to a hydrochloride salt by acidification with IPA/HCl solution to yield 65 g of the racemic cevimeline hydrochloride with 65:35 ratio of cis:trans isomer by HPLC.
Example III
[0029] Dichloromethane (200 ml) was charged in a vessel. To this was charged (10.0 g) of racemic mixture of cis/trans cevimeline having a 65:35 ratio of cis:trans isomer. The reaction mass was stirred for 10 to 15 minutes at 20 to 25° C. 1.0 ml of IPA was charged to the reaction mass. The reaction mass was cooled to −5 to 0° C. Anhydrous titanium tetrachloride (7.0 ml) was charged to the reaction mass over 5 to 10 minutes. After addition, stirring was continued for 18 to 24 hours at 20 to 30° C. After completion of the reaction, the reaction mass was cooled to 0 to 5° C. Process water (100 ml) was added and the mass was stirred for 10 to 15 minutes. The layers were separated. The dichloromethane layer was washed with 5% sulfuric acid (2×50 ml) and the layers separated. To the combined aqueous layer, di-isopropyl ether (100 ml) was charged and the pH of the solution adjusted 10 to 12. The layers were separated and the aqueous portion re-extracted with di-isopropyl ether (50 ml). The combined organic layer was dried with anhydrous sodium sulfate. To the dried solution was charged IPA/HCl solution to acidic. The separated solid was stirred and filtered at 0 to 5° C. for 30 to 45 minutes. The solid was washed with chilled di-isopropyl ether (2×10 ml). The solid was suction dried at 50 to 60° C. under vacuum to yield 6.5 g of the product with cis isomer of cevimeline hydrochloride >90% purity by HPLC.
Example IV
[0030] Dichloromethane (200 ml) was charged to a vessel and to this was added (10.0 g) of racemic mixture of cis/trans cevimeline with a ratio of about 65:35 cis:trans isomer as prepared in Example III. The reaction mass was stirred for 10 to 15 minutes at 20 to 25° C. 1.0 ml IPA was charged to the vessel and the reaction mass cooled to −5 to 0° C. 1.0 ml DMSO was charged to the mass. Anhydrous titanium tetrachloride (7.5 ml) was added drop wise over 5 to 10 minutes. After this addition, stirring was continued for 6 hours at 20 to 30° C. The reaction mass was then cooled and processed as in Example III to yield 6.0 g of the product of cis isomer of cevimeline hydrochloride with >90% purity by HPLC.
Example V
[0031] Charged chloroform (35 ml) to a vessel and to this charged (5.0 g) of a racemic mixture of cis/trans cevimeline with about 65:35 ratio of cis:trans isomer. Stirred the reaction mass for 10 to 15 minutes at 20 to 25° C. Cooled the reaction mass to −5 to 0° C. Charged anhydrous titanium tetrachloride (3.5 ml) drop wise over 10 to 15 minutes. After addition, continued stirring for 24 hours at 20 to 30° C. The reaction mass was then cooled and processed as in Example III to yield 3.0 g of the product of cis isomer of cevimeline hydrochloride with >90% purity by HPLC.
Example VI
[0032] Charged di-isopropyl ether (DIPE) (100 ml) in a vessel and to this charged cevimeline hydrochloride (10.0 g with cis isomer >90% purity and prepared by any one of the above methods). Cooled to 0 to 10° C. Charged concentrated sodium hydroxide solution drop wise to adjust the solution to pH above 12 (pH around 12 to 14). Stirred for 15 to 20 minutes and separated the DIPE layer. Reextracted the aqueous layer with DIPE and distilled off the organic layer, leaving a thick residue. To this residue, charged acetone (10 ml) and continued the distillation to remove the traces of DIPE. Charged acetone (100 ml) to the residue and stirred for 10 to 15 minutes. Cooled the solution to 0 to 5° C. Charged concentrated sulfuric acid (2.5 ml) slowly at the above temperature range. Stirred the separated solid for 30 minutes at 0 to 5° C. Raised the reaction mass temperature to 55 to 60° C. Stirred for 2 hrs and then cooled to 0 to 10° C. Stirred for 30 minutes. Filtered the solid and washed it with chilled acetone (10 ml). Suction dried the solid well and dried the solid at 50 to 60° C. to obtain 9.0 g of the product of cis isomer of cevimeline sulfate with >97% purity HPLC.
[0033] Charged cevimeline sulfate to a solution of di-isopropyl ether (100 ml) and cooled the solution to 0 to 10° C. Charged concentrated sodium hydroxide solution drop wise to adjust the pH of the solution to above 12. Stirred for 15 to 20 minutes and separated the DIPE layer. Reextracted the aqueous layer with DIPE and dried the total DIPE layer with anhydrous sodium sulfate. Cooled the dried DIPE layer to 0 to 10° C. and charged IPA/HCl solution to acidic. Stirred the separated solid at this temperature for 30 to 45 minutes. Filtered the solid and washed it with chilled DIPE (10.0 ml). Suction dried the solid well and dried the solid at 50 to 60° C. to obtain 6.0 g of the cevimeline hydrochloride with cis isomer >97% by HPLC.
Example VII
[0034] Charged DIPE (60 ml) to a vessel and to this charged cevimeline hydrochloride (prepared from Example VI) (6.0 g with 97% cis isomer). Cooled the solution to 0 to 10° C. Charged concentrated sodium hydroxide solution drop wise to adjust pH of the solution to above 12. Stirred for 15 to 20 minutes and separated the DIPE layer. Re-extracted the aqueous layer with DIPE and distilled off the organic layer, leaving a thick residue. To this residue, charged acetone (6.0 ml) and continued the distillation to remove traces of DIPE. Charged acetone (60 ml) to the residue and stirred for 10 to 15 minutes. Cooled the solution to 0 to 5° C. Charged sulfuric acid (3.0 ml) slowly at the above temperature range. Raised the reaction mass temperature to 55 to 60° C. Charged sulfuric acid (0.6 ml). Stirred for 2 hrs and then cooled to 0 to 10° C. Stirred for 30 minutes. Filtered the solid and washed it with chilled acetone (10 ml). Suction dried the solid well and dried the solid at 50 to 60° C. to obtain 6.0 g of the product as cevimeline sulfate with cis isomer purity >99.5% by HPLC.
[0035] Charged DIPE (60 ml) to a vessel and to this charged the above cevimeline sulfate (99.5% cis isomer). Cooled the solution to 0 to 10° C. Charged concentrated sodium hydroxide solution drop wise to adjust the pH of the solution to above 12. Stirred for 15 to 20 minutes and separated the DIPE layer. Re-extracted the aqueous layer with DIPE and dried the total DIPE layer with anhydrous sodium sulfate. Cooled the dried DIPE layer to 0 to 10° C. and charged IPA/HCl solution to acidic. Stirred the separated solid at this temp for 30 to 45 minutes. Filtered the solid and washed it with chilled DIPE (9.0 ml). Suction dried the solid well and dried the solid at 50 to 60° C. to obtain 3.6 g of the cevimeline hydrochloride with cis isomer >99.5% with individual impurities below 0.10% by HPLC.
Example VIII
[0036] Charged ethyl methyl ketone (40 ml) to a vessel and to this charged cevimeline free base with cis isomer >90% by HPLC (4.0 g) (prepared by any one of the above methods given in Examples III to V). Stirred for 10 to 15 minutes to obtain a clear solution. Cooled the solution to 0 to 5° C. Charged concentrated sulfuric acid (1.3 ml) drop wise over 30 minutes and stirred the resultant liberated sulfate salt for 30 minutes at 0 to 5° C. Then slowly raised the temperature to reflux temperature and continued the reflux for 60 to 90 minutes. The reaction mass was then cooled and processed as in Example VI to yield 4.0 g of the product cevimeline sulfate with cis isomer >97% purity by HPLC.
[0037] Charged DIPE (260 ml) to a vessel and to this charged the above cevimeline sulfate (4.0 g with 97% cis isomer). Cooled the solution to 0 to 10° C. and proceeded as in Example VI to obtain 2.5 g of cevimeline hydrochloride with cis isomer >97% purity by HPLC.
Example IX
[0038] Charged DIPE (26 ml) to a vessel and to this charged cevimeline hydrochloride (2.6 g with 97% cis isomer as prepared in Example VIII). Cooled the solution to 0 to 10° C. Charged concentrated sodium hydroxide solution drop wise to adjust pH of the solution to above 12. Stirred for 15 to 20 minutes and separated the DIPE layer. Re-extracted the aqueous layer with DIPE and distilled off the organic layer, leaving a thick residue. To this residue, charged acetone (6.0 ml) and continued the distillation to remove traces of DIPE. Charged acetone (60 ml) to the residue and stirred for 10 to 15 minutes. Cooled the solution to 0 to 5° C. Charged sulfuric acid (1.3 ml) slowly at the above temperature range. Raised the reaction mass temperature to 55 to 60° C. Charged sulfuric acid (0.26 ml) and proceeded as in Example VII to yield 2.6 g of cevimeline sulfate with >99.5% cis isomer by HPLC.
[0039] Charged DIPE (60 ml) to a vessel and to this charged the above cevimeline sulfate (2.6 g, 99.5% cis isomer). Cooled the solution to 0 to 10° C. and proceeded as in Example VII to yield 1.7 g of the cevimeline hydrochloride with cis isomer >99.5% with individual impurities below 0.10% by HPLC.
Example X
[0040] Charged methyl isobutyl ketone (60 ml) and to this charged cevimeline free base with cis isomer >90% by HPLC (5.0 g) (prepared by any one of the above methods given in Examples III to V). Stirred for 10 to 15 minutes to obtain a clear solution. Cooled the solution to 0 to 5° C. Charged concentrated sulfuric acid (1.6 ml) drop wise over 30 minutes and stirred the resultant liberated sulfate salt for 30 minutes at 0 to 5° C. Then slowly raised the temperature to reflux temperature and continued the reflux for 60 to 90 minutes. The reaction mass was then cooled and processed as in Example VI to yield 3.0 g of the cevimeline sulfate with cis isomer >97% purity by HPLC.
[0041] Charged DIPE (26 ml) to a vessel and to this charged the above cevimeline sulfate (3.0 g with 97% cis isomer). Cooled the solution to 0 to 10° C. and proceeded as in Example VI to obtain 2.0 g of cevimeline hydrochloride with cis isomer >97% purity by HPLC.
Example XI
[0042] Charged DIPE (20 ml) to a vessel and to this charged cevimeline hydrochloride prepared from Example X (2.0 g with 97% cis isomer). Cooled the solution to 0 to 10° C. Charged concentrated sodium hydroxide solution drop wise to adjust pH of the solution to above 12. Stirred for 15 to 20 minutes and separated the DIPE layer. Re-extracted the aqueous layer with DIPE and distilled off the organic layer, leaving a thick residue. To this residue, charged acetone (2.0 ml) and continued the distillation to remove traces of DIPE. Charged acetone (20 ml) to the residue and stirred for 10 to 15 minutes. Cooled the solution to 0 to 5° C. Charged sulfuric acid (1.0 ml) slowly at the above temperature range and raised the reaction mass temperature to 55 to 60° C. Charge sulfuric acid (0.2 ml) and proceeded as in Example VII to yield 2.0 g of cevimeline sulfate with >99.5% cis isomer by HPLC.
[0043] Charged DIPE (20 ml) to a vessel and to this charged the above cevimeline sulfate (99.5% cis isomer). Cooled the solution to 0 to 10° C. and proceeded as in Example VII to yield 1.7 g of the cevimeline hydrochloride with cis isomer >99.5% with individual impurities below 0.10% by HPLC.
Example XII
[0044] Charged toluene (50 ml) and to this charged cevimeline free base with cis isomer >90% (5.0 g) (prepared by any one of the above methods given in examples III to V). Stirred for 10 to 15 minutes to obtain a clear solution. Cooled the solution to 0 to 5° C. Charged concentrated sulfuric acid (1.3 ml) drop wise over 30 minutes and stir the resultant liberated sulfate salt for 30 minutes at 0 to 5° C. Then slowly raised the temperature to reflux temperature (100 to 115° C.) and continued the reflux for 60 to 90 minutes. The reaction mass was then cooled and processed as in Example VI to yield 3.5 g of cevimeline sulfate with cis isomer >97% purity by HPLC.
[0045] Charged DIPE (35 ml) to a vessel and to this charged the above cevimeline sulfate (3.5 g with 97% cis isomer). Cooled the solution to 0 to 10° C. and proceeded as in Example VI to obtain 2.0 g of cevimeline hydrochloride with cis isomer >97% purity by HPLC.
[0046] Charged DIPE (20 ml) to a vessel and to this charged cevimeline hydrochloride (prepared from Example XII) (2.0 g with 97% cis isomer). Cooled the solution to 0 to 10° C. Charged concentrated sodium hydroxide solution drop wise to adjust pH of the solution to above 12. Stirred for 15 to 20 minutes and separated the DIPE layer. Re-extracted the aqueous layer with DIPE and distilled off the organic layer, leaving a thick residue. To this residue, charged acetone (2.0 ml) and continued the distillation to remove traces of DIPE. Charged acetone (20 ml) to the residue and stirred for 10 to 15 minutes. Cooled the solution to 0 to 5° C. Charged sulfuric acid (1.0 ml) slowly at the above temperature range and raised the reaction mass temperature to 55 to 60° C. Charged sulfuric acid (0.2 ml) and proceeded as in Example VII to yield 2.0 g of cevimeline sulfate with >99.5% cis isomer by HPLC.
[0047] Charged DIPE (20 ml) to a vessel and to this charged the above cevimeline sulfate (99.5% cis isomer). Cooled the solution to 0 to 10° C. and proceeded as in Example VII to yield 1.8 g of the cevimeline hydrochloride with cis isomer >99.5% with individual impurities below 0.10% by HPLC.
[0048] While the preferred embodiments have been described and illustrated it will be understood that changes in details and obvious undisclosed variations might be made without departing from the spirit and principle of the invention and therefore the scope of the invention is not to be construed as limited to the preferred embodiment. | Pharmaceutical-grade compounds containing cis-2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine having a purity >99.0% by HPLC with less than 0.5% of trans-2-methylspiro(1,3-oxathiolane-5,3′)quinuclidine are provided. | 2 |
RELATED APPLICATION
[0001] This application is a continuation of U.S. application Ser. No. 14/968,101, filed Dec. 14, 2015, which is a continuation of U.S. application Ser. No. 14/528,695, filed Oct. 30, 2014, now U.S. Pat. No. 9,212,040, which is a continuation of U.S. application Ser. No. 12/704,217, filed Feb. 11, 2010, now U.S. Pat. No. 8,910,674, which claims the benefit of U.S. Provisional Patent Application No. 61/151,770, filed on Feb. 11, 2009. These applications are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
[0002] The invention relates generally to dispensing fluids. More specifically, the invention provides methods and systems for dispensing fluids, such as beverages, using wireless technology.
BACKGROUND OF THE INVENTION
[0003] The present invention relates to dispensing fluids, such as beverages, using wireless technology. Retail establishments, for example fast food restaurants and convenience stores, often utilize fountain drink dispensers to dispense servings of different beverages to multiple users. Using such beverage dispensers allows consumers to purchase a cup or other containers that may be filled with one or more beverages at the beverage dispenser. Unfortunately, however, traditional systems cannot adequately monitor the user's actions to confirm the user obtained the beverage paid for. Indeed, some “premium” beverages may be offered at the beverage dispenser, however, there is no efficient method or system to efficiently monitor whether consumers pay for the drink they consume.
SUMMARY OF THE INVENTION
[0004] The following presents a simplified summary of the disclosure in order to provide a basic understanding of some aspects of the invention by way of exemplary embodiments. These embodiments do not define key or critical elements of the invention or to delineate the scope of the invention. The following summary merely presents some of the concepts of the disclosure in a simplified form as a prelude to the more detailed description of aspects of the invention provided below.
[0005] Aspects of the invention relate to a beverage dispensing system, having at least one beverage container and at least one beverage dispenser. The beverage container may include a sidewall disposed around a central bottom, wherein the bottom is distal to an opening for receiving a beverage, and a container wireless transceiver associated with the container. In one embodiment, the container wireless transceiver may be affixed to the bottom of the container. In other embodiments, the container wireless transceiver may be affixed to the sidewall of the container. Yet in other embodiments, the container wireless transceiver may be located in an impermeable layer between the sidewall and the bottom of the container, wherein the impermeable layer is not in fluid communication with the location where the beverage would be received in the opening. Additionally, the container wireless transceiver may be configured to transmit an electronic signal indicative that the beverage container is validated to receive a beverage and whether the beverage container is properly located to receive the beverage from the valve of the drink dispenser.
[0006] In aspects in accordance with this invention, the beverage dispenser may include a housing, a valve extending from the housing configured to dispense the beverage into the container located below the valve, and a dispenser wireless transceiver located in close proximity to the beverage dispenser configured to communicate with the container wireless transceiver on the beverage container. The beverage dispenser may further include a valve lever that extends from the housing, wherein in some embodiments the dispenser wireless transceiver may be located on the valve lever. In other embodiments, the valve lever may include a lever backing that extends from the housing, wherein the dispenser wireless transceiver is located on the lever backing. The dispenser wireless transceiver may be configured to receive a return signal from a compatible container indicative that the beverage container is validated to receive the beverage from the beverage dispenser and whether the beverage container is properly located to receive the beverage. Additionally, when the dispenser wireless transceiver is positioned such that upon placement of a compatible container in a location to properly receive the beverage from the valve, the dispenser wireless transceiver may be aligned with the container wireless transceiver of the beverage container. In yet another embodiment, when the beverage container is placed under the valve, the dispenser wireless transceiver may transmit a first electronic signal to the beverage container and the container wireless transceiver may transmit a second electronic signal to the dispenser wireless transceiver to confirm proper placement under the valve and to confirm that the beverage container is a compatible container to receive the beverage from the valve, and wherein the valve subsequently dispenses the beverage into the beverage container.
[0007] Further aspects of the invention are related to a beverage container configured to communicate with a beverage dispenser that includes a dispenser wireless transceiver. The beverage container may include a sidewall disposed around a central bottom, wherein the bottom is distal to an opening for receiving a beverage and a container wireless transceiver affixed to the container, with the container wireless transceiver configured to communicate with the dispenser wireless transceiver. In one embodiment, the container wireless transceiver may be affixed to the bottom of the container. In other embodiments, the container wireless transceiver may be affixed to the sidewall of the container. Yet in other embodiments, the container wireless transceiver may be located in an impermeable layer between the sidewall and the bottom of the container, wherein the impermeable layer is not in fluid communication with the location where the beverage would be received in the opening. Additionally, the container wireless transceiver may be configured to transmit an electronic signal indicative that the beverage container is validated to receive a beverage and whether the beverage container is properly located to receive the beverage from the valve of the drink dispenser.
[0008] Further aspects of the invention are related to a beverage dispenser configured to communicate with a beverage container that includes a wireless transceiver. The beverage dispenser may include a housing, a valve extending from the housing configured to dispense the beverage into the container located below the valve, and a dispenser wireless transceiver located in close proximity to the beverage dispenser configured to communicate with the container wireless transceiver on the beverage container. The beverage dispenser may further include a valve lever that extends from the housing, wherein in some embodiments the dispenser wireless transceiver may be located on the valve lever. In other embodiments, the valve lever may include a lever backing that extends from the housing, wherein the dispenser wireless transceiver is located on the lever backing. The dispenser wireless transceiver may be configured to receive a return signal from a compatible container indicative that the beverage container is validated to receive the beverage from the beverage dispenser and whether the beverage container is properly located to receive the beverage. Additionally, when the dispenser wireless transceiver is positioned such that upon placement of a compatible container in a location to properly receive the beverage from the valve, the dispenser wireless transceiver may be aligned with the container wireless transceiver of the beverage container. In yet another embodiment, when the beverage container is placed under the valve, the dispenser wireless transceiver may transmit a first electronic signal to the beverage container and the container wireless transceiver may transmit a second electronic signal to the dispenser wireless transceiver to confirm proper placement under the valve and to confirm that the beverage container is a compatible container to receive the beverage from the valve, and wherein the valve subsequently dispenses the beverage into the beverage container.
[0009] Further aspects of the invention are related to a method for dispensing fluids for example with the container and beverage dispenser or beverage dispensing system as described above. The method may include the steps of: 1) sensing a beverage container in close proximity to a beverage dispenser; 2) transmitting a first electronic signal to the beverage container from a dispenser wireless transceiver located in close proximity to the beverage dispenser; 3) transmitting a second electronic signal to the dispenser wireless transceiver from a container wireless transceiver associated with the container; and 4) dispensing the fluid from the beverage dispenser to the beverage container. Additionally, the transmission of the first electronic signal and the second electronic signal may confirm the proper placement of the beverage container under the beverage dispenser and may confirm that the beverage container is a compatible container to receive a fluid from the beverage dispenser.
[0010] These and other features and advantages of the present invention will become apparent from the description of the preferred embodiments, with reference to the accompanying drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The present disclosure is illustrated by way of example and not limited in the accompanying figures in which like reference numerals indicate similar elements and in which:
[0012] FIG. 1 illustrates a perspective view of an exemplary beverage dispensing system in accordance with aspects of the invention;
[0013] FIG. 2 illustrates a perspective view of an exemplary beverage container that may be used with the beverage dispensing system from FIG. 1 in accordance with aspects of the invention;
[0014] FIG. 3A illustrates a front perspective view of an exemplary beverage dispenser that may be used with the beverage dispensing system from FIG. 1 in accordance with aspects of the invention; and
[0015] FIGS. 3B and 3C illustrate rear perspective views of the beverage dispenser from FIG. 3A in accordance with aspects of the invention.
[0016] The reader is advised that the attached drawings are not necessarily drawn to scale.
DETAILED DESCRIPTION OF THE INVENTION
[0017] In the following description of various examples of the invention, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various example structures, systems, and steps in which aspects of the invention may be practiced. It is to be understood that other specific arrangements of parts, structures, example devices, systems, and steps may be utilized and structural and functional modifications may be made without departing from the scope of the present invention. Also, while the terms “top,” “bottom,” “front,” “back,” “side,” and the like may be used in this specification to describe various example features and elements of the invention, these terms are used herein as a matter of convenience, e.g., based on the example orientations shown in the figures. Nothing in this specification should be construed as requiring a specific three dimensional orientation of structures in order to fall within the scope of this invention.
[0018] An exemplary beverage dispensing system may comprise one or more components shown in FIGS. 1 through 3C . As illustrated in FIGS. 1 through 3C , the beverage dispensing system 10 may comprise a container 100 and a beverage dispenser 200 . As is shown in FIG. 1 , the beverage dispensing system may include one or more beverage dispensers 200 . Additionally, as shown in FIG. 1 , the beverage dispensing system may include beverage dispensers in accordance with the present invention and traditional beverage dispensers utilized in the prior art, represented by the box labeled “PRIOR ART” in FIG. 1 .
[0019] As illustrated in FIG. 2 , aspects of the invention relate to novel beverage containers that can be utilized with a beverage dispenser 200 in accordance with this invention, such as container 100 . Exemplary container 100 may contain a sidewall 102 disposed around a central bottom 104 , wherein the bottom 104 is distal to an opening (not shown) for receiving a beverage. While the exemplary container 100 is shown as an open-faced cup, those skilled in the art will readily appreciate that other containers that are configured to hold a beverage, such as a bottle, can, bowl, or any structure that may receive a fluid, may be utilized in accordance with one or more embodiments of the invention.
[0020] Additionally, the container 100 may be made of any materials known and used in the art. The container 100 may be made the materials, such as: plastic, Styrofoam™, paper, or metal in accordance with aspects of this invention. Additionally, the container 100 may be any size as known and used in the art without departing from this invention.
[0021] In accordance with one embodiment, the container 100 comprises a wireless transceiver 106 . The wireless transceiver 106 may be configured to utilize one or more forms of wireless technology, including but not limited to: radio frequency identification (RFID), electronic article surveillance (EAS), Bluetooth, cellular, and/or any transmissions in accordance with IEEE 802.xx. Indeed, any component(s) configured to transmit and/or receive wireless signals is within the scope of this disclosure. In accordance with aspects of this invention, the wireless transceiver 106 may be in the form of RFID, similar to examples such as automated automobile toll collection or security access cards. Additionally, the wireless transceiver 106 may be in the form of an EAS system. EAS systems are generally used in a retail setting for security and to help protect against shoplifting.
[0022] RFID systems generally may include one or more RFID tags that may be inductively-coupled, capacitively-coupled, active, semi-passive, and passive. In general, each RFID tag works by first, storing data within an RFID tag's microchip. The RFID tag may include an antenna that receives electromagnetic energy from an RFID reader's antenna. Using power from the RFID tag's internal battery or power harvested from the reader's electromagnetic field, the tag may then send radio waves back to the reader. The reader may then receive the RFID tag's radio waves and interpret the frequencies as meaningful data.
[0023] EAS systems may include technologies such as radio frequency (RF) systems, electromagnetic systems, acousto-magnetic systems, or microwave systems. RF systems generally work with an RF tag or label attached to a product, with the RF tag being basically a miniature, disposable electronic circuit and antenna. The RF tag or label may respond to a specific frequency emitted by a transmitter antenna. For electromagnetic systems, a magnetic, iron-containing strip may be attached to the product. This electromagnetic strip can be activated or deactivated using a highly intense magnetic field. The electromagnetic strip may respond to electromagnetic field transmitted from a transmitter antenna. For acousto-magnetic systems, a transmitter sends a radio-frequency signal in pulses, which in turn may energize a tag within the transmitted zone. When the pulse ends, the tag responds, emitting a single frequency signal like a tuning fork. While the transmitter is off between pulses, the tag signal is detected by the receiver and is checked to ensure it is the correct frequency. If all these criteria are met, the tag is signaled as correct (or alarmed in the example of a security system).
[0024] These wireless systems are different systems known and used in the art at the present time, however, any component(s) configured to transmit and/or receive wireless signals is within the scope of this invention.
[0025] As shown in FIG. 2 , wireless transceiver 106 may be affixed or molded to the bottom 104 of the beverage container 100 . In other embodiments, however, the wireless transceiver 106 may be located on, affixed to, or otherwise associated with a sidewall 102 of the container 100 . Yet in further embodiments, the wireless transceiver 106 may be located within a secondary compartment of container 100 . For example, an impermeable layer or structure may be placed between the sidewall 102 and/or the bottom 104 of the container 100 to create an internal compartment that is not in fluid communication with the location where a beverage would be received in the opening (not shown). As discussed in more detail below, the wireless transceiver 106 may be configured to transmit information to a beverage dispenser, such as a dispenser 200 shown in FIGS. 3A through 3C .
[0026] An exemplary beverage dispenser 200 is shown in FIGS. 3A through 3C . The term “beverage” has been used to readily convey exemplary embodiments to reader, however, those skilled in the art will readily appreciate that any liquid, gel, or similar product, including for example, concentrated syrup, is within the scope of the invention. Therefore, while the below embodiments are explained in relation to a ready-made beverage, readers are advised that the dispensing of any liquid, gel, or similar product is within the scope of the invention. The exemplary beverage dispenser 200 may generally resemble a traditional fountain-drink dispenser and may comprise a valve 202 , a housing 204 , and a valve lever 212 .
[0027] As illustrated in FIGS. 3A through 3C , the housing 204 may include a front housing area 206 and a rear housing area 207 . The front housing area 206 may include a push-button 208 . The push-button 208 may include a logo of the beverage to be dispensed from the beverage dispenser 200 . Additionally, the push-button 208 may illuminate at different times, such as when the push-button 208 is pushed, when the beverage dispenser 200 is ready, or when the beverage dispenser 200 is communicating with a container 100 . Additionally, the push-button 208 may illuminate and blink at varying times or varying frequencies to signal events or activities. In accordance with aspects of this invention, the push-button 208 may only be a button, that may not be pushed at all. Pressing the push-button 208 may control the flow of the beverage from the valve 202 to the container 100 . Additionally, in accordance with other aspects of this invention, the housing 204 may include a lever actuator that may actuate the valve 202 and dispense the beverage from the valve 202 to the container 100 .
[0028] In addition to the push-button 208 , the front housing 206 may also include electronics 210 . The electronics 210 may be self-contained within the front housing 206 as is illustrated specifically in FIG. 3C . The electronics 210 may be in the form of a circuit board or other similar control electronics capable of controlling the functionality and operability of the beverage dispenser 200 . The electronics 210 may also help facilitate communication between the container 100 and the beverage dispenser 200 .
[0029] The rear housing 207 may include a set of connections 220 to the beverage dispensing system 10 . As illustrated in FIGS. 3B and 3C , these connections 220 may include tubing or similar-type connection ends configured to attach to the tubing or connection of the beverage dispensing system 10 . The connections 220 may also be capable of connecting directly to individual beverage lines, such as when the beverage dispenser 200 is not used as part of a beverage dispensing system 10 .
[0030] As illustrated in FIGS. 3A through 3C , the beverage dispenser may also include a valve 202 . The valve 202 may protrude or extend from the housing 204 as is shown in FIG. 3A . While the term “valve” is used throughout this disclosure, those skilled in the art will readily appreciate that any outlet configured to dispense a liquid is within the scope of invention. The valve 202 may be configured to dispense a beverage into a compatible container 100 . Additionally, the valve 202 may include a relay or electromechanical switch that turns the valve on or off (or enabled or disabled) based on the presence of a compatible container 100 .
[0031] Additionally, as illustrated in FIGS. 3A through 3C , the beverage dispenser may include a valve lever 212 . The valve lever 212 may protrude or extend from the housing 204 as shown in FIG. 3A . The valve lever 212 may be of any of various shapes and sizes without departing from this invention. As discussed in more detail below, the use of the valve lever 212 may be further supplanted or replaced with a wireless transceiver, such as a wireless transceiver 216 located on the beverage dispenser 200 . The valve lever 212 may also include a lever backing 218 . The lever backing 218 may extend from the housing 204 , and more specifically, from the rear housing 207 . The lever backing 218 may include the wireless transceiver 216 as illustrated in FIG. 3A . For example, the wireless transceiver 216 may be located on the lower portion of the lever backing 218 . Additionally, the beverage dispenser 200 may not include the lever backing 218 , and in this instance, the transceiver 216 may be located on the valve lever 212 . In another embodiment in accordance with this invention, the beverage dispenser 200 does not include a valve lever 212 and only includes the lever backing 218 , wherein the transceiver 216 may be located on the lever backing 218 .
[0032] As illustrated in FIGS. 3A through 3C , the beverage dispenser 200 and more specifically, the valve 202 , may dispense a beverage into a compatible container, such as the container 100 as illustrated in FIG. 2 . Construction of exemplary containers has been described above in relation to FIG. 2 , and is also known in the art. As discussed below, however, in certain embodiments the presence and/or orientation of a wireless transceiver 106 within, affixed to, imbedded or otherwise associated with container 100 may be determinative of whether a beverage receptacle may be considered a compatible container 100 .
[0033] In certain embodiments, valve 202 may be in operative communication with a valve lever 212 which may be mechanical, electrical, or electro-mechanical. In one embodiment having valve lever 212 , pressure may be placed upon the valve lever 212 (for example, along the direction of arrow 214 ), as container 100 is placed under the valve 202 . Pressure upon the valve lever 212 may transmit a signal (electrical or mechanical) indicating the presence of a container, such as container 100 . In one embodiment where transceiver 216 is located on the lower portion of the lever backing 218 , a container 100 configured for use with dispenser 200 may include the wireless transceiver 106 located on or near its bottom 104 , such that the wireless transceiver 216 of the beverage dispenser 200 is aligned with wireless transceiver 106 of the container 100 .
[0034] In one embodiment, the wireless transceiver 216 of the dispenser 200 is configured to transmit an electronic signal. The transmission of the electronic signal may be set to a continuous loop, such that the signal is continually transmitted. Yet in other embodiments, the transmission of the electronic signal may be dependant on one or more conditions, such as determined or influenced by a timer, a motion sensor (which may external to the dispenser 200 ) or any other hardware or software in communication with dispenser 200 . As discussed above in relation to the embodiment shown in FIG. 3A , the wireless transceiver 216 may be located in the lever backing 218 of the valve lever 212 , such that a consumer may press the container 100 against it to dispense the beverage from valve 202 . In one embodiment, the electronic signal transmitted from wireless transceiver 216 is received by wireless transceiver 106 on container 100 when container 100 is correctly placed to receive a beverage from the valve 202 . In this regard, one or both of the wireless transceivers 106 , 216 are configured to transmit a signal that may only be received by the other when each are within a threshold distance from each other. Yet in other embodiments, the signal transmitted from one of the transceivers 106 , 216 may be received by the other transceiver 106 , 216 at a distance that is further than when the container 100 is properly placed to receive a beverage from the valve 202 , however, the dispenser 200 is configured such that a threshold signal strength or proximity measurement is required for the valve 202 to dispense the beverage, wherein the threshold strength or proximity measurement is met only when the container 204 is properly located to receive a beverage from valve 202 .
[0035] In one embodiment, upon receiving the electronic signal from the wireless transceiver 216 , the wireless transceiver 106 of the container 100 may transmits a return signal indicating that the container is located in a proper configuration to receive the beverage, such as the placement of the container 100 in relation to valve 202 shown in FIG. 3A . In this regard, the beverage is only dispensed when the container 100 having a wireless transceiver 106 transmitting a valid electronic return signal is correctly placed to receive the beverage.
[0036] In one embodiment, the wireless transceiver 106 is configured to transmit information to enable a beverage to be dispensed from a specific valve 202 . Yet in other embodiments, the wireless transceiver 106 is configured to enable the dispensing of a beverage from several different valves. In one such embodiment, at least one valve dispenses a fluid that is different than the fluid dispensed from at least one other valve. In another embodiment, the wireless transceivers 106 , 216 do not require complex circuitry that requires information to be rewritten with additional information, such as the amount of beverage dispensed, quantity of times the container has been utilized at one or more dispensers 200 , or other information. Yet in other embodiments, information, including one or more of the parameters above (and/or other parameters) may be transmitted. Furthermore, in certain embodiments, one or more of the electronic signals transmitted from the wireless transceiver(s) 106 , 216 does not include information regarding the purchaser or user of container 100 . Yet in other embodiments, such information regarding the purchaser or user of container 100 may be utilized.
[0037] In one embodiment, one or more of the electronic signals to be transmitted from container 100 to the transceiver 216 is determined and configured before a consumer purchases the cup. Therefore, in certain embodiments, this would reduce the complexity and time required for transactions related to selling or otherwise providing container 100 to a consumer.
[0038] As those skilled in the art will readily appreciate in view of this disclosure, either wireless transceiver 106 , 216 may be located at other locations associated with the beverage dispenser 200 and the container 100 .
[0039] The advantages and benefits of a beverage dispensing system in accordance with this invention may be readily apparent to those of skill in the art. Specifically, one advantage of the beverage dispensing system 10 may be controlled access to premium beverages at a beverage dispensing system. Because of the transmissions between the transceiver 106 on the container 100 and the transceiver 216 on the beverage dispenser 200 , the beverage dispenser system 10 may provide controlled access to premium beverages. Another advantage for the beverage dispensing system 10 may be that the RFID/EAS equipped valves and wireless systems are generally more difficult to bypass than systems that utilize mechanical or contact/switch systems as used in the prior art. Additionally, the beverage dispensing system 10 does not require physical contact between the container 100 and the valve 202 to activate the beverage dispenser system 10 , thereby making the beverage dispensing system 10 of the present invention easier to use and generally more sanitary.
CONCLUSION
[0040] The present invention is disclosed above and in the accompanying drawings with reference to a variety of examples. The purpose served by the disclosure, however, is to provide an example of the various features and concepts related to the invention, not to limit the scope of the invention. One skilled in the relevant art will recognize that numerous variations and modifications may be made to the aspects described above without departing from the scope of the present invention, as defined by the appended claims. | Methods and systems directed to dispensing fluids, such as beverages, using wireless technology are provided. Aspects relate to a beverage dispenser with a dispensing system housing, a valve housing positioned exterior to the dispensing system housing and extending from the dispensing system housing. The valve housing may be configured to dispense a beverage and include self-contained electronics disposed within an interior area of the valve housing. In some embodiments, the beverage dispenser has one or more additional valve housings positioned exterior to the dispensing system housing. The valve housing may be configured to dispense a beverage and include self-contained electronics disposed within an interior area of the valve housing. | 6 |
FIELD OF THE INVENTION
The present invention relates to two dimensional color image editing generally and more particularly to a system and method for generating shadows in two dimensional color images.
BACKGROUND OF THE INVENTION
Methods for generating artificial shadows in two dimensional (2D) images are known in the art, one example described in coassigned published European Patent Application No. 622,748 A2.
Generally speaking, the generation of an artificial shadow in a 2D color image involves two main steps, namely, defining an area on the 2D image to be shadowed and applying a suitable color to the selected area.
Conventional methods for generating artificial shadows in 2D color images include full manual methods and semi-manual methods.
In the manual method, a user which edits a 2D color image employs an interactive tool, such as an air brush with which it interacts with the 2D image displayed on the color editing workstation. Typically, the user will mark by hand an area to be shadowed, then will mask it with a masking file and will replace the original color with a color generated from a separate color editing function, such as a degrade function or a vignette function. This method is time consuming since it involves both manual selection of the shadowed area and work on separate files, i.e., the mask file, and the coloring file (degrade or vignette).
In the semi-manual method, a user defines an area to be shadowed as described for the full manual method. Then an automatic shadowing function colors the selected area to be shadowed. This method described in the above coassigned patent application is advantageous with respect to the full manual method, however, the user is still forced to mark the area to be shadowed, a time consuming task which demands a high level of expertise from the user.
Both methods are available as commercial applications operating with a color editing workstation, such as the PRISMA workstation, commercially available from Scitex Corporation Ltd of Herzlia, Israel.
SUMMARY OF THE INVENTION
The present invention seeks to provide an improved system and method for generating artificial shadows in 2D color images which overcome the drawbacks associated with the full manual and semi-manual methods of the prior art.
Another object of the present invention is to provide a semi-automatic method for generating artificial shadows in 2D color images which requires relatively small user intervention.
Yet another object of the present invention is to provide a method for generating artificial shadows in 2D color images which enables to remake the shadows created for one object in the image to other different objects, while preserving the basic shadow qualities for all objects, in a way that assures optical consistency of the shadows for all the objects in a page.
Yet another object of the present invention is to provide a system and method for generating improved artificial shadows in 2D color images, the shadows having improved colors with respect to prior art methods.
There is thus provided, according to a preferred embodiment of the present invention, a method for generating an artificial shadow in a two dimensional color image which includes the following steps:
A. providing a shadow scenes library, each shadow scene representing at least one artificial shadow orientation with respect to an object forming the shadow. Preferably, but not necessarily, the shadow scene library is represented by a graphic representation displayable to the user;
B. receiving a user input, the user selecting one of the shadow scenes and an object in the two dimensional image to be shadowed; and
C. forming an artificial shadow to the object to be shadowed in accordance with the selected shadow scene.
Further, the method may also include the step of selecting at least one additional object in the two dimensional color image and forming a shadow to each of the selected objects in accordance with the selected shadow scene.
Still further, the method may also include the step of defining a geometrical feature defining the object. According to a preferred embodiment of the present invention, the geometrical feature is rectangular.
According to a preferred embodiment of the present invention, the step of forming includes the steps of calculating the artificial shadow from the object and the object scene and moving the calculated artificial shadow to a selected location with respect to the object. Additionally, the step of forming may include the step of applying at least one color to the artificial shadow.
According to yet another preferred embodiment of the present invention, the step of forming includes the steps of calculating the artificial shadow from the geometrical feature defining the object and the selected object scene and applying at least one color to the artificial shadow.
Further, the step of calculating preferably includes the steps of:
A. converting the geometrical feature defining the object from a two dimensional representation to a three dimensional representation;
B. providing parameters defining the selected shadow scene;
C. determining a three dimensional representation of the artificial shadow defined by a corresponding geometrical feature based on the parameters and the three dimensional representation of the object obtained by the converting; and
D. converting the three dimensional representation of the geometrical feature defining the artificial shadow to a two dimensional representation thereof, thereby providing the artificial shadow.
According to a preferred embodiment of the present invention, the parameters include an indication of the artificial shadow angle with respect to the horizon, the height of the object above a reference level, such as the ground level, a location of the light source and any combination therebetween.
There is also provided, according to the present invention, apparatus for carrying out the steps of the methods of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood and appreciated more fully from the following detailed description taken in conjunction with the appended drawings in which:
FIG. 1 is a schematic illustration of a color image workstation suitable for executing the method for generating artificial shadows in a 2D color image of the present invention;
FIG. 2 is a schematic pictorial illustration of a plurality of icons representing the shadow scenes of the present invention.
FIG. 3 is a schematic flow chart illustration of a preferred method of the present invention for generating artificial shadow in a 2D color image;
FIG. 4 is a schematic flow chart illustration of the shadow control file generation step of the method of FIG. 3; and
FIG. 5 is a schematic flow chart illustration of the calculation step of FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference is now made to FIGS. 1 and 2 which illustrate a workstation executing an application constructed and operative according to a preferred embodiment of the present invention, respectively.
The computer workstation of FIG. 1, generally referenced 10, may be any interactive workstation, such as the Prisma workstation, commercially available from Scitex Corporation Ltd. of Herzlia, Israel, which comprises a CPU 12, a memory 14, user input tools, such as keyboard 16 and mouse 18 and a display, such as a CRT display 20. CPU 12 and Memory 14 are shown in block diagram form in FIG. 1 for illustration purposes only.
According to a primary aspect of the present invention, a library of shadow scene icons is stored in memory 14, each shadow scene represented by a corresponding icon 21 on the CRT 20 (FIG. 2). A user selects an icon 21 from the CRT 20, thereby initiating a semi-automatic tool operative on a pre-defined object to produce a preliminary shadow area to the object in the image. The preliminary shadow area may later be modified manually by the user.
Each of the shadow scenes stored in memory 14 represented by the icons 21 in the library, encapsulate therein several specific shadow qualities. A non limiting example of these qualities may include the length of the shadow, its relative size, its direction and other geometrical properties. Yet the shadow scene is general and not related to any specific object.
The use of the shadow scene icons 21 automates the shadow area definition and provides a repeatable method for reproducing the same shadow on many different objects, while preserving the general appearance of the shadows.
Prior to operating the shadow scene library, as best seen in FIG. 3, the user selects a 2D image to be edited as shown in 22. In the preferred embodiment, the 2D image is a raster image. The selected image provided in 22 has been provided to workstation 10 by any suitable way, a non limiting example being an image provided by scanning an original color image employing a scanner 2 (FIG. 1 ).
Next, as indicated by 24, the user provides an object control file which defines for each pixel in the image provided in 22 whether it forms part of an object or part of the background.
In step 26, the user chooses an object to be shadowed and in 28 the user selects an icon which represents a shadow scene to be applied to the selected object. Preferably, the user invokes a shadow icon 21 from a collection of predefined shadow scene library stored in memory 14. The selected icon activates the shadow scene parametric file on the chosen object. The shadow icon holds the shape of the shadow visually so the user can predict the effect of the icon on its object.
The user chooses the object by any suitable way employing one of the interactive tools. Non limiting examples include the indication of a rectangle of pixels in which the objects reside (object rectangle), or by indicating a pixel that is part of the selected object, from which point the entire rectangle which defines the object is thereby defined.
It will be appreciated that the term object rectangle refers herein to any geometrical feature defining the object and a rectangle is used as a non limiting example thereof.
In step 30, a shadow control file is calculated based on the inputs of step 26 and step 28, as described in detail with reference to FIGS. 4-5 hereinbelow, whereby an artificial shadow is generated and displayed on display 20.
In step 32, the user addresses the question of whether the location of the artificial shadow generated automatically with respect to the selected object satisfies in terms of quality. If assessed positively the process continues by an interactive step in which the user provides coloring parameters to the system at 34 and the generated shadow is colored in 36. If the answer in step 32 is negative an intermediate user interactive step is initiated in which the user changes the location of the generated shadow with respect to the object before the coloring steps 34 and 36.
The user may now select another object at 26 and may apply the same selected shadow scene at 28 so as to create automatically substantially similar artificial shadows for a plurality of objects in the 2D color image.
Reference is now made to FIG. 4 which illustrates step 30 (FIG. 3) of calculating the shadow control file.
The shadow control file receives as input the pixel values of the object rectangle and the characteristics of the shadow scene and outputs an artificial shadow to the selected object in accordance therewith.
As shown in FIG. 4, the process starts in step 40 in which a pixel of the object rectangle is loaded. In step 42, it is verified that the loaded pixel is an object pixel. This step is necessary since as described hereinabove, a geometrical area defining the object is selected in which not all pixels are actual object pixels.
If the pixel is not an object pixel, the process starts again from 40 by loading the next pixel of the object rectangle. If the pixel is an object pixel, the process continues at 44 in which a check is performed as to whether the pixel P has a corresponding value in the artificial shadow control file S as described in detail hereinbelow. If P does not have a corresponding value the process begins again at 40. If P has a solution, then the corresponding value and location of S is calculated (step 46) and the values of the shadow control file are updated (step 48) with that value for the location of S. The process continues until all object pixels are mapped into corresponding pixels in a corresponding shadow rectangle and the shadow control file is accordingly updated. Finally, the process terminates at step 50.
Reference is now made to FIG. 5 which illustrates the calculation of each location and value of S from corresponding location and value of P so as to generate a shadow rectangle from the object rectangle. It will be appreciated that each of the object rectangle and the shadow rectangle in the 2D plane are defined by two values, the topleft x and y values and the bottomright x and y values, denoted TofLeft(x), TopLeft(y), BottomRight(x) and BottomRight(y), respectively.
In 52, P is converted from its 2D coordinates to a three dimensional (3D) normalized coordinates, i.e. for each value of P (Px,Py) a normalized value Pn (Nx,Ny, 0) is calculated. In the preferred embodiment, X and Y are measured from the topleft point of the image raster file. An exemplary calculation for the 2D to 3D conversion is described by equation 1 as follows:
Nx= Px-TopLeft(x)!/ Max(Height,Width)!-NewDX/2 Ny= BottomRight(y)-Py!/Max(Height,Width) (1)
wherein TopLeft(x) and BottomRight(y) are the x value of the top left point and the y value of the bottom right point of the object rectangle, Height is the number of pixels in each line in the object rectangle, Width is the number of lines in the object rectangle and NewDX is calculated as follows:
NewDX=Width/Max(Height,Width) (2)
wherein Max(Height,Width) is the maximum between Height and Width of the rectangle.
The normalized values of P (Nx,Ny,0) are further modified in accordance with the shadow scene parameters entered in 54. The shadow scene parameters include at least a representation of a shadow plane and a location of a light source. In one exemplary shadow scene, an indication of the artificial shadow angle with respect to the horizon, the height of the object above a reference level, such as the ground level and the location of the light source for which the shadow is generated may be provided.
At step 56, the conversion P (Nx,Ny,0) to S (Nx,Ny,Nz) is made wherein a Z value denoted Nz is derived from the transformation from the object rectangle plane to the artificial shadow plane.
A preferred method for converting P to S is by projecting each light ray produced by the light source defined as part of the characterization of the shadow scene into the plane defined by the shadow rectangle as is well known in the art.
An exemplary calculation may be based on a parameter representing the time travelled by an artificial light ray from a light source defined as part of the characterization of the shadow scene through the object rectangle onto the shadow rectangle.
In a preferred calculation based on a time related parameter, a light ray which travels through the object plane is denoted three time values, 0 at the light source, 1 at the object plain and more than 1 in the shadow rectangle plane.
Provided the light source coordinates L(Lx,Ly,Lz) and the point the coordinates of the point of intersection through the object plane P(Nx,Ny,0), the light ray can be calculated as follows:
LightRay(t)=L(Lx,Ly,Lz)+ P(Nx,Ny,0)-L(Lx,Ly,Lz)!*t (3a)
Then, solving a three free parameters equation set for the parameter t
LightRay(t)=Shadow plane (k,l) (3b)
wherein Shadow plane (k,l) are the coordinates of projection on the plane coinciding with the shadow rectangle, the coordinates for S can be solved from
S(Nx,Ny,Nz)=LightRay(t') (3c)
wherein t' is the solution for the free parameter t.
If the parameter t' is smaller or equal to 1, a projection point on S is not found and the process terminates at 62 (FIG. 5). If t' is larger then 1 than the process continues at 58 as described hereinbelow.
At step 58, the shadow point S (Nx,Ny,Nz) is converted back into 2D image screen coordinate system as follows:
ShadowX=(Sx+NewDX/2) MAX(Height,Width)+TopLeft(x) (4a)
ShadowY=BottomRight(y)-Sy MAX(Height,Width) (4b)
ShadowZ=Sz MAX(Height,Width) (4c)
wherein the parameters are the corresponding parameter in the shadow rectangle to those in the object rectangle. The point (Shadow X, Shadow Y, Shadow Z) is written now in the shadow control file. In the preferred embodiment, all pixels in the shadow control file are set at initiation to infinity, and for each solution (Shadow X, Shadow Y, Shadow Z), Sz is written in location Sx, Sy, thus adding a shadow pixel to the shadow control file.
Finally, the point (ShadowX, ShadowY) updates the shadow rectangle (step 48 of FIG. 4) as follows:
if (ShadowX<TopLeft(x)) then TopLeft(x)=ShadowX (5a)
if (ShadowX>BottomRight(x)) then BottomRight(x)=ShadowX (5b)
if (ShadowY<TopLeft(y)) then TopLeft(y)=ShadowY (5c)
if (ShadowY>BottomRight(y)) then BottomRight(y)=ShadowY (5d)
As shown best in FIG. 3, once the generation of the artificial shadow is completed as described hereinabove, the user may color the pixels within the shadow rectangle i.e., the pixels with Sz value which is not infinity, in any desired color employing any user interactive tool and/or application known in the art. Non limiting examples of such tools are the vignette or degrade tools commercially available with the above mentioned Prisma workstation.
An example of the user input in the coloring step 36 includes a user input of the darkest color in the artificial shadow, the brightest color in the artificial shadow and a shadow curve for defining the change in color between the darkest and brightest points. Further, the coloring step 36 may take into account the Sz values of the pixels within the shadow rectangle so as to assign a color in accordance with the distance from the object.
According to a preferred embodiment of the present invention, pixels within the shadow rectangle which overlap with pixels of the object are not colored as these pixels do not appear in the final image with the artificial shadow since they are being hidden by the object and therefore retain the color of the object.
While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention, all of which fall within the scope of the present invention exist. For example, the user may generate the same artificial shading for a plurality of objects in the 2D image as described above but with different shadow colors or color curves.
It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention is defined only by the claims that follow: | A method and apparatus for carrying out the method for generating an artificial shadow in a two dimensional color image. The method includes the steps of providing a shadow scenes library, each shadow scene representing at least one artificial shadow orientation with respect to an object forming the shadow, receiving a user input, the user selecting one of the shadow scenes and an object in the two dimensional image to be shadowed, and forming an artificial shadow to the object to be shadowed in accordance with the selected shadow scene. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The subject invention generally pertains to a loading dock and more specifically to a dock seal disposed around a doorway of the dock.
2. Description of Related Art
When an exterior doorway of a building is used as a loading dock for vehicles, especially trucks, the perimeter of the doorway typically includes a seal known as a dock pad. The dock pad seals off gaps that would otherwise exist between the exterior face of the building and the back end of the truck. This allows cargo from the rear of the truck to be loaded or unloaded while dockworkers and the cargo are protected from the weather. Usually a side dock pad runs vertically along each lateral edge of the doorway, and a top or head pad runs horizontally along the doorway's upper edge. A typical pad comprises a resiliently compressible foam core protected by a fabric outer covering. Sealing is often provided by backing the truck up against the pad, so that the pad compressively conforms to the shape of the rear of the truck.
When a truck backs into a loading dock, in many cases, taillights on the rear of the truck press against the dock pad. This often occurs with taillights that are located along the upper rear edge of the truck, whereby the lights push against the head pad that is mounted over the doorway. Normally, this does not create a problem. However, if the driver of the truck inadvertently leaves the lights on for an extended period (e.g., while the truck is being loaded or unloaded), the dock pad absorbs much of the heat generated by the taillights. The pad's core being made of foam, which is inherently a poor conductor of heat, tends to keep the heat concentrated to a relatively small area of the pad near the light. Thus, the temperature of that area can rise significantly. Excessively high temperatures can degrade the materials of the pad, or in some extreme cases, may even cause portions of the pad to burn or melt.
Perhaps one solution would be to make a dock pad of materials that could tolerate higher temperatures. However, such an approach would likely compromise other desirable qualities of the pad, such as abrasion resistance, puncture resistance, weather resistance, compressibility, resilience, lightweight, appearance, etc., as the materials currently being used are often chosen for the purpose of optimizing these qualities.
SUMMARY OF THE INVENTION
In order to provide a dock seal that can tolerate heat generated by a vehicle's taillight, a dock pad comprising a compressible foam core with a pliable outer cover includes a heat shield that helps protect the foam core and its outer cover from excessive heat.
In some embodiments, a heat shield is interposed between a dock pad's foam core and its cover to retain at least some of advantages of the cover.
In some embodiments, a dock pad is provided with a heat shield that has appreciable thermal conductivity to help disperse heat.
In some embodiments, a dock pad is provided with a heat shield that has appreciable reflectivity to reflect some heat away from a foam core of the dock pad.
In some embodiments, a dock pad is provided with a heat shield that can withstand a higher temperature than a foam core of the dock pad, whereby the heat shield helps protect the foam core from heat.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a dock pad that includes a heat shield.
FIG. 2 is a cross-sectional view taken along line 2 — 2 of FIG. 1 .
FIG. 3 is a cross-sectional view similar to that of FIG. 2 , but of another embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENT
To create a weather seal between the rear of a truck 10 (or some other vehicle) and the perimeter a loading dock doorway 12 , a dock pad 14 (or dock pad assembly) is installed, as shown in FIG. 1 . In this example, dock pad 14 includes a side pad 16 mounted along each lateral edge of doorway 12 , and a top or head pad 18 installed along the doorway's upper edge. Pads 16 and 18 are resiliently compressible, so as truck 10 backs up against them, the pads compressively and sealingly conform to the contour of the truck's rear edges.
To provide dock pad 14 with durability and resilient compressibility, pad 14 includes a resiliently compressible foam core 20 covered by a tough outer cover 22 , as shown in FIG. 2 . In this example, core 20 consists of a polyurethane or foamed polyester, such as, for example, an L24 open-cell polyurethane foam provided by Leggett & Platt of Carthage, Mo. It should be appreciated by those skilled in the art; however, that a wide variety of other synthetic or natural foams may also work well. In some embodiments, cover 22 is a 3022_MFRLPC_DC7 material provided by the Seaman Corporation of Wooster, Ohio. Other examples of cover materials would include, but are not limited to, HYPALON, canvas duck, rubber-impregnated fabric, and coated nylon fabric.
In assembling pad 14 , cover 22 wraps at least partially around core 20 , and the two are attached to a relatively rigid backer 24 , such a formed steel channel or a wood board. Backer 24 , in this example, provides a mounting surface 26 that facilitates the installation of pad 14 . A conventional fastener or anchor can be used to attach backer 24 to a wall 28 of a loading dock 30 . In some embodiments, cover 22 attaches to the side edges of backer 24 by any one of a variety of fasteners including, but not limited to, screws, VEECRO, rivets, hooks, and adhesive. Core 20 can be frictionally held to cover 22 , or the two can be joined in a more positive manner. For example, cover 22 can be connected to core 20 with adhesive, straps, hooks, VELCRO, stitches, screws, etc.
To make pad 14 more resistant to heat, such as heat generated by a taillight 32 pressing against certain points 34 on a sealing surface 36 of pad 14 , a heat shield 38 is attached to pad 14 . In some embodiments, heat shield 38 is incorporated within a Commercial Material RTCM01, which consists of two flexible sheets or layers of perforated aluminum foil reinforced with a polyethylene scrim or fabric, as provided by Radiant Technology, of Dallas, Tex. The flexibility of shield 38 is preferably sufficient to allow dock pad 14 to compressively conform to the contour of the truck's rear edges and then decompress to the pad's original shape. Heat shield 38 can be attached to pad 14 using adhesive, friction, straps, stitches, and/or various other fasteners. Shield 38 can be attached to the exterior or interior of pad 14 , however; shield 38 is preferably installed between cover 22 and foam core 20 for structural, functional, and aesthetic reasons.
Placing shield 38 underneath cover 22 , helps keep cover 22 exposed to the outside, thus taking advantage of the cover's toughness, weather resistance and pliability. Moreover, shield 38 preferably has a higher reflectivity than core 20 and cover 22 . This can be beneficial in cases where the cover can withstand a higher temperature than the core, wherein “withstand a higher temperature” means a material can be raised to the higher temperature and then substantially recover its original properties after its temperature returns to normal. For example, if the foam of core 20 has an auto ignition point (i.e., temperature at which the material self-ignites without being triggered by a spark or a flame) of 700 degrees Fahrenheit and cover 22 has an auto ignition point of 900 degrees, then heat shield 38 with high reflectivity could reflect heat away from the foam and redirect it into cover 22 , which may be able to handle the heat better. In some embodiments, both cover 22 and core 20 have a lower auto ignition point than heat shield 38 (e.g., when shield 38 is one of the two layers of aluminum foil contained within Commercial Material RTCM01).
To reduce peak temperatures of core 20 and/or cover 22 when heated by taillight 32 , heat shield 38 is made of a material that has a higher thermal conductivity than core 20 and/or cover 22 . The maximum temperature at areas of concentrated heat, such as points 34 , is reduced by shield 38 being able to effectively disperse the heat over a broader area. The term, “thermal conductivity” refers to a material's ability to conduct heat of a given temperature gradient along a given length and through a given cross-sectional area of the material, thus thermal conductivity is a property of the material itself, and is generally independent of the material's shape. A typical unit of measure for thermal conductivity would be (Btu)/(hr)(ft)(° F.).
To provide even greater heat protection, another embodiment, similar to that of FIG. 2 , provides a dock pad 14 ′ with two heat shields 38 ′, as shown in FIG. 3 . It is believed that additional heat protection is provided by the additional overall thickness of the two shields and perhaps partially provided by virtue of an additional slight air interface 40 that may exist between the two shields 38 ′. Moreover, for a given total thickness, two individual shields instead of one relatively thick one is more flexible, just as a stack of individual cards is more flexible than a stack of cards whose faces are glued together.
A strap 42 inserted through a slit 44 in foam core 20 ′ helps hold the two shields 38 ′ in place. A loop 46 at each end of strap 44 engages holes 48 in shields 38 ′; however, strap 42 could attach to shields 38 ′ in a variety of other ways as well. Also, strap 42 could feed around the back of core 20 ′ to eliminate the need for slit 44 ; however, strap 42 extending through slit 44 helps keep strap 42 and shields 38 ′ from shifting along the length of a pad.
Although the invention is described with reference to a preferred embodiment, it should be appreciated by those skilled in the art that various modifications are well within the scope of the invention. For example, although the illustrated dock pads have cross-sections that are generally rectangular, various other shapes are also well within the scope of the invention. Moreover, the shape of the head pad could be different than that of the two side pads. One or more heat shields can be applied to just the head pad, just the side pads, or applied to both the head and side pads. Therefore, the scope of the invention is to be determined by reference to the claims that follow. | A compressible seal for a loading dock includes a pliable heat shield that helps protect the seal from concentrated heat generated by a truck's taillight being pressed against the seal. The seal includes a compressible foam core protected by a tough outer covering. The heat shield is preferably placed against the foam core, just underneath the cover. The shield reflects heat away from the foam and helps disperse the heat over a broader area to reduce the peak temperature of any hot spots. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to the construction and installation of boat dock assemblies.
The formation of boat docks from portable sections pivotally interconnected with each other and having foldable and adjustably extensible legs, is well known. Prior U.S. patents relating to such dock assemblies known to applicant consist of U.S. Pat. Nos. 2,948,121, 3,043,109, 3,380,257, 3,568,451, and 3,620,027. Each of such prior art docking arrangements have a limited purpose or utility or a special construction designed to meet certain specific requirements. It is therefore an important object of the present invention to provide an exceptionally versatile method of erecting a boat dock to meet different requirements by use of a plurality of unique portable dock sections that are readily assembled and installed without requiring entry into the water or requiring use of special tools and fasteners.
Another object is to provide a novel construction for portable dock sections made of interchangeable parts assembled without use of fasteners to meet different dimensional requirements.
Yet another object is to provide a dock assembly that may be firmly stabilized in position despite installational variations.
SUMMARY OF THE INVENTION
In accordance with the present invention various docking arrangements are formed from the assembly of portable dock sections interconnected by hinge devices that accommodate up 230° relative angular displacement, each hinge device being concealed below a tread retaining formation substantially bridging the space between the adjacent dock sections above the hinge device. Each dock section is formed by decking members interconnected in close parallel spaced relation by spacer interlock elements having gripping arms engaged with adjacent decking members below upper tread retaining portions thereof. The decking members are interconnected with transversely extending side rail members enclosing liquid retaining chambers or cavities adapted to be filled with water to stabilize the dock assembly after it is installed in place. Hydraulically and/or mechanically adjustable leg assemblies support the dock sections above the water and are provided with pivotally separable clam-like shells as foot elements to form a firm footing as well as to facilitate removal or retraction from any location. The dock sections may be transported to and pivotally assembled in place without entering the water by pivotally lowering each section in sequence into position. By use of a rope and winch arrangement, outer dock sections may be elevated out of the water and disassembled for removal.
These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation view of a typical dock arrangement assembled and installed in accordance with the present invention.
FIG. 2 is a top plan view of the dock arrangement shown in FIG. 1.
FIG. 3 is an enlarged partial section view taken substantially through a plane indicated by section line 3--3 in FIG. 2.
FIG. 4 is an enlarged partial section view taken substantially through a plane indicated by section line 4--4 in FIG. 2.
FIG. 5 is a partial section view taken substantially through a plane indicated by section line 5--5 in FIG. 4.
FIG. 6 is a partial section view taken substantially through a plane indicated by section 6--6 in FIG. 3.
FIG. 7 is a perspective view showing disassembled locking elements associated with each of the dock sections forming the dock assembly shown in FIGS. 1 and 2.
FIG. 8 is an enlarged partial section view taken substantially through a plane indicated by section 8--8 in FIG. 2.
FIG. 9 is an enlarged partial section view taken substantially through a plane indicated by section line 9--9 in FIG. 1.
FIG. 10 is an enlarged partial section view taken substantially through a plane indicated by section line 10--10 in FIG. 9.
FIG. 11 is an enlarged transverse section view taken substantially through a plane indicated by section line 11--11 in FIG. 1.
FIG. 12 is a partial section view taken substantially through a plane indicated by section line 12--12 in FIG. 11.
FIG. 13 is a partial side elevation view showing the removal of a dock section.
FIG. 14 is an enlarged partial section view taken substantially through a plane indicated by section line 14--14 in FIG. 13.
FIG. 15 is an enlarged partial section view taken substantially through a plane indicated by section line 15--15 in FIG. 13.
FIG. 16 is an enlarged partial section view taken substantially through a plane indicated by section line 16--16 in FIG. 2.
FIG. 17 is an enlarged transverse section view taken substantially through a plane indicated by section line 17--17 in FIG. 16.
FIG. 18 is a partial side elevation view showing the assembly and lowering of a dock section into position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings in detail, FIGS. 1 and 2 illustrate a typical boat dock assembly generally referred to by reference numeral 10. In the arrangement shown, the dock assembly includes five elongated dock sections 12 extending along a straight path, as viewed from above in FIG. 2, from dry land 14 out over a body of water 16. A sixth dock section extends laterally from the side of one of the dock sections over the water and is interconnected therewith by a corner cross walk member 18 as shown in FIG. 2. The dock sections 12 are hingedly interconnected with each other and each has a pair of extensible leg assemblies 20 connected thereto at one longitudinal end as shown in FIGS. 1. A brace 22 is associated with each leg assembly to support the assembled dock assemblies in their elevated positions as shown. It should of course be appreciated that other dock arrangements may be formed by the assembly of different numbers of dock sections 12 to meet different dock requirements.
Referring now to FIGS. 2, 3 and 4 in particular, the construction of a typical dock section 12 will become apparent. Each dock section is assembled from a plurality of parallel spaced decking members 24 interconnected with a pair of side rail members 26. The length and number of decking members may be varied while the side rail members are cut to the length of the dock section. The decking and side rail members thus form the basic components of the dock section and are fabricated as metallic extrusions of uniform and constant cross-section as more clearly seen in FIGS. 3 and 4. Spacer locking elements 28 interconnect adjacent decking members 24 at their longitudinal ends in close parallel spaced relation to each other as shown in FIG. 3 while interlock elements 30 interconnect the decking members 24 with the side rail members 26 at right angles as shown in FIG. 4.
Each decking member 24 as more clearly seen in FIG. 3 includes a tread retaining portion 32 from which a pair of side retainer projections 34 and an intermediate retainer projection 36 extend upwardly alongside of a pair of curved recesses 38 in which a pair of treads 40 are seated, the treads being made of wood, carpeting or some other material presenting a suitable friction surface for walking purposes. A pair of supporting ribs 42 depend from the tread retaining portion 32 from which a pair of grip arms 44 extend at right angles thereto in generally parallel spaced relation below the portion 32. Sawtooth grip formations 46 project toward each other from the grip arms 44 and the tread portion 32 for engagement with mating formations on elastically deflectable arms 48 and 50 associated with one of the spacer locking elements 28 aforementioned as more clearly seen in FIG. 5. The assembled decking members 24 are supported on a tube or support beam 52 which extends substantially the entire length of the dock section so as to structurally rigidify assembly of decking members.
Each spacer locking element 28 as more clearly seen in FIGS. 5 and 7 includes a tubular portion 58 of rectangular cross-section having generally parallel vertical sides 60 from which the grip arms 48 and 50 extend. The locking elements 28 interconnect adjacent decking members at the ends abutting the side rail members 26 as shown in FIG. 4. Each interlock element 30 includes a web 62 from which a pair of elastically deflectable grip arms 64 and 66 extend. The web 62 abuts the rectangular portion 58 of a spacer element 28 with its grip arms projecting therethrough as shown in FIG. 4 so as to engage grip teeth on the abutting side rail member 26 in order to interconnect the assembled decking members with the side rail members.
Each side rail member 26 also includes a tread retaining portion 68 having tread retainer projections for holding three treads 70 as shown in FIG. 4. An outer side 72 interconnects the tread portion 68 with a bottom 74 to which an inner side 76 is connected. The side 76 is connected to the tread portion 68 by a grip receiving portion 78 forming a support ledge for the assembled locking element 28 and 30. The interconnected sides, bottom and portions 68 and 78 of the side rail member also enclose a liquid retaining chamber 80 adapted to be either filled with water or drained. When drained, the side rail members 26 form part of a relatively lightweight dock section capable of being manually carried and assembled in place. Once installed in a dock assembly, the chambers 80 formed in the side rail members 26 may be filled with water to stabilize the assembly.
The dock sections are pivotally interconnected with each other by hinge assemblies 82. As shown in FIG. 3, the adjacent longitudinal ends of the dock sections are closed by end plates 84 and 86 associated with the hinge assembly 82. The end plates are locked to decking members at the ends by grip arms 88 and 90 projecting therefrom. A curved bearing arm 92 projects from plate 84 and is received within a cavity formed between arms 94 and 96 projecting from plate 86 to establish a hinge connection accommodating up to 230° relative angular movement between the adjacent dock sections. The bearing arms 92, 94 and 96 underlie a tread retaining formation formed integrally with the arms 94 and 96 and projecting from plate 86. Thus, the tread 100 will substantially bridge the space between the longitudinal ends of adjacent dock sections occupied by the hinge assembly 82 to protect and conceal the hinge connection. A similar hinge assembly 82' as shown in FIG. 4 interconnects a dock section at one longitudinal end with the side rail member 26 when two dock sections are interconnected at right angles to each other. The hinge assembly 82' is the same as 82 except that plate 84' is secured to side 72 without any grip arms.
Each dock section is supported by a pair of leg assemblies 20 as aforementioned. One type of leg assembly 20 shown in FIG. 9 includes a bracket 102 secured to the side rail member to support it at a 5° angle to a plane perpendicular to the vertical axis of the leg assembly. A connector 104 is pivotally connected by pivot bolt 106 to the bracket 102 and is in turn pivotally connected by pivot bolt 108 to an outer tubular housing 110 to which the brace 22 is connected as shown in FIG. 1. The pivot bolt 108 also extends through an upper head 112 from which a hydraulic cylinder 114 is suspended within the housing 110. A piston rod 116 is displaceable from the lower end of cylinder 114 and is connected by pin 118 to a curved foot element 120 through an extensible sleeve 119. On short legs, the foot element 120 may be connected directly to the piston rod through a pin without any sleeve 119. The foot element has an anchor rod 122 connected thereto for insertion into the earth so as to firmly anchor the leg assembly in place. The element 120 provides a sufficiently large bearing surface to resist shifting and tilting of the leg assembly. The piston rod 116 has a piston element 124 connected to the upper end thereof as shown in FIG. 10. Fluid under pressure is supplied to the upper end of the cylinder 114 through a passage 126 in the head 112. The head is therefore connected by conduit section 128 and elbow 130 to a valve 132 having an inlet fitting 134 through which a quick disconnect coupling 136 may connect the valve to a water pump (not shown) through conduit 138. Water drawn from the body of water 16 may therefore be pumped into each leg assembly 20 for extension thereof to a desired length by displacement of the piston element 124 in order to firmly anchor each dock section in place through its foot element 120. To lower a dock section, the valve 132 may be opened to release fluid and shorten the leg assembly.
Leg assemblies 20' supporting some dock sections may be provided with another type of foot assembly 140 as shown in FIGS. 11 and 12. The extensible element 142 of the leg assembly 20' has a pair of connecting wing elements 144 welded to the lower end thereof in alignment with each other. Each wing element 144 is pivotally connected by a pivot pin 146 to a half-shell element 148. The curved shell elements 148 form a clam-like configuration in the solid line position shown in FIG. 12 to provide a firm bearing support for the leg assembly. The shell elements 148 may pivot to the position shown by dotted line in FIG. 12 to facilitate withdrawal of the foot assembly from the earth in which it is embedded when disassembling the dock.
FIGS. 16 and 17 show another form of leg assembly 20" which may be utilized for support of some dock sections. The leg assembly 20" is also extensible, but by mechanical means. A bracket 150 is secured as by welding to the bottom 74 of the side rail member 26 associated with the dock section. A connector 152 is connected by a pair of aligned fastener assemblies 154. An outer tubular housing 156 is secured as by welding to the connector 152 and depends therefrom. A tubular extensible element 158 abuts the connector 152 in its fully retracted position as shown in FIG. 16, the lower end of the extensible element 158 being connectible to a foot assembly by means of a connecting bolt 160. An internally threaded nut element 162 is mounted in axially fixed position within the element 158. An elongated screw element 164 threadedly extends through the nut element 162 and is connected at its upper end within connector 152 to an actuating shank 166 by means of a cotter pin 168. The actuator shank extends through aligned openings in the bracket 150 and the bottom 74 of the side rail member into chamber 80 and terminates at its upper end at section 170 adapted to be grasped by a tool for rotation of the screw element 164. Access to actuator section 170 is provided by means of an opening 172 formed in the tread portion 32 of the side rail member. A plug 40 is accordingly removed to expose opening 172 when it is desired to either extend or retract the extensible element 158. Rotation of the screw elememt 164 causes axial displacement of the nut 162 and the element 158 axially fixed thereto.
Some of the dock sections are provided with bumper assemblies generally referred to by reference numeral 174 in FIGS. 1 and 8. Each bumper assembly includes a clamp assembly 176 secured to the bottom 74 of the side rail member 26 as shown in FIG. 8, the clamp assembly being operative to detachably anchor the end portion of a curved bumper rod element 178 that extends outwardly and upwardly in spaced relation to the side rail member and then curves downwardly. The portion of the bumper rod 178 spaced outwardly from the side rail member is covered with a suitable impact absorbing material 180. The outer side 72 of the side rail member 26 may also have secured thereto a retainer bracket 182 holding a plurality of parallel bumper ribs 184 in order to provide impact protection for the dock section between the bumper assemblies 174.
FIG. 18 illustrates the manner in which a dock section 12 is added onto a previously anchored dock section when assembling a dock assembly. The disassembled dock section as shown by dotted line is transported by a wheeled cart 185 to the end of the anchored dock section and is hooked onto it to form the hinge assembly 82 by tilting the cart. The hingedly assembled dock section is then lowered into the water by pivotal displacement thereof off the cart as shown by arrow 187 in FIG. 18.
FIG. 13 illustrates the manner in which a dock section 12 is removed. A gin pole 186 is secured to the longitudinal end portion of an anchored dock section so as to position thereabove a guide 188 for a rope 190 connected at one end to the dock section being raised out of the water. The other end of the rope 190 extends from a manually operated winch assembly 194 detachably secured to the previously anchored dock section. As more clearly seen in FIG. 15, the gin pole 186 is received at its lower end within a sleeve 198, which is connected by a bolt assembly 200 to a mounting bracket 202 welded to a bearing plate 196 resting on the treads 40 of the dock section. A pair of prongs 199 welded to the plate 196 depend therefrom between adjacent decking members 24 in straddling relation to the support tube 52. The winch assembly 194 aforementioned includes a rope sheave 204 on which the rope 190 is wound or unwound, the sheave being rotated by means of a crank handle 206 interconnected with the sheave through suitable gearing (not shown). The sheave and gearing are mounted by means of a bracket 208 secured to a rearwardly inclined support plate 210. The support plate 210 is secured to a base plate 212 and support post 214. As more clearly seen in FIG. 14, the base plate 212 is secured by a fastener assembly 216 to an anchor plate 218 that rests on top of the decking members 24. A vertical L-shaped anchor fin 220 is secured as by welding to the anchor plate 218 and depends therefrom between the adjacent decking members and is held assembled in place by a lower element 222 to embrace the support tube 52. Thus, the winch assembly 194 may be firmly anchored in place for performing its function.
The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A boat dock assembled from portable sections hingedly connected to each other and provided with foldable and adjustably extensible leg assemblies. Each section is formed from tread retaining decking members made of extruded metal sections interconnected in close parallel spaced relation by interlocking elements. Pivotally separable half-shell foot elements are connected to the leg assemblies for stabilized support of the dock sections. | 8 |
TECHNICAL FIELD
The present invention relates generally to the field of flight control systems for aircraft and relates particularly to a system for automatically controlling the velocity of an aircraft.
DESCRIPTION OF THE PRIOR ART
Many modern aircraft have flight control systems for maintaining selected flight parameters at or near selected values. These parameters may include altitude, heading, attitude, and/or airspeed, and the control system maintains each parameter by operating flight control systems of the aircraft. For example, altitude may be controlled through use of flight control surfaces, such as elevators, or through use of the throttle to control the airspeed of the aircraft. These flight control systems are usually closed-loop feedback control systems, allowing for the input from the control system to respond to changes in the controlled parameter.
Typical closed-loop systems control the velocity of the aircraft using either the airspeed or the inertial velocity. Airspeed is defined as the forward velocity of the aircraft relative to the air mass in which the aircraft is flying, whereas inertial velocity is defined as the forward velocity of the aircraft relative to the ground over which the aircraft is flying. The flight control system compares the commanded velocity (airspeed or inertial velocity) to the measured velocity, and the difference between the commanded velocity and the measured velocity is the velocity error. When the velocity error is not zero, the control system inputs a corrective command to one or more system of the aircraft, such as throttles in a fixed-wing aircraft or rotor blade pitch in a helicopter, to increase or decrease the measured velocity in order to achieve a zero velocity error. Typically, the corrective command is proportional to the velocity error
A schematic view of a typical prior-art airspeed control system is shown in FIG. 1 . System 11 comprises a command input device 13 for sending commands to aircraft actuators 15 , and the airspeed of the aircraft is measured by a sensor 17 in feedback loop 19 . The airspeed command from device 13 and the negative of the measured airspeed output from sensor 17 are summed at node 21 , producing an airspeed error signal sent to actuators 15 . System 11 operates actuators 15 to reduce this airspeed error signal to zero.
In calm air, typical closed-loop feedback systems operate to control airspeed fairly well. However, an aircraft flying in a turbulent-air environment will pass from an air mass moving in one direction into an air mass moving in another direction. The effects of this turbulence will cause positive and negative longitudinal acceleration forces on the aircraft. These accelerations change the airspeed and inertial velocity of the aircraft, which creates a velocity error that the control system attempts to eliminate. In a fixed-wing aircraft, the control system will command a change in the throttle position, which changes engine power and produce additional accelerations. In helicopters or other rotary-wing aircraft, such as tiltrotors, the control system may command a change in the throttle position, engine nacelle position, and/or blade pitch inputs, which can also cause a change in pitch attitude of o the aircraft. Changes in engine power and pitch attitude are transmitted into the cabin of the aircraft, producing undesirable acceleration and motion effects on passengers.
An example will illustrate the effects of turbulent air on the operation of a flight control system, such as system 11 , which is commanded to maintain a selected airspeed. FIGS. 2A through 2E are graphs over time of the input and response for a sustained head-on gust using the prior-art system of FIG. 1 , and FIGS. 3A through 3E are similar graphs showing the input and response for a transient head-on gust.
In an aircraft flying through air that has no velocity (calm air), the control system measures little or no velocity error, and the accelerations caused by negligible changes in throttle input are not felt by the passengers. However, when the aircraft encounters air that is moving in the opposite direction of the aircraft, the airspeed sensor will detect the increased airspeed. For example, graph 2 A shows the results of a sustained 30 ft/sec head-on gust encountered at 5 seconds on the timeline and which ramps to its maximum value in approximately 1 second. The gust causes the measured airspeed, shown in FIG. 2B , to rise from the commanded airspeed of 200 kts to approximately 207 kts at around 7.5 seconds. This also causes a decrease in groundspeed, as shown in FIG. 2C . In response to the increased airspeed, control system 11 commands a change in throttle position to reduce engine power in order to achieve the original airspeed. The throttle position versus time is shown in FIG. 2D , and the position is decreased from about 36 degrees just before the gust is encountered to about 12 degrees afterward at 8 seconds, reducing engine power. The aircraft is thus decelerated to an even slower groundspeed, reaching a total decrease in groundspeed of 30 kts at about 14 seconds.
After peaking at 207 kts, the airspeed begins to decrease due to the reduction in engine power, and the airspeed falls below 200 kts at around 11 seconds. Simultaneously, the throttle position is ramping up to increase engine power to attain and maintain the commanded airspeed, but control system 11 causes throttle position overshoot that does not settle out until approximately 35 seconds. In addition to the longitudinal velocities, the vertical velocity of the aircraft is affected, as shown in FIG. 2E , with a +8 ft/sec maximum and a −9 ft/sec minimum.
When the aircraft moves back into a stationary air mass (zero wind speed), the measured airspeed will be less than the commanded airspeed. The control system then commands a change in throttle position to increase engine power, causing acceleration of the aircraft back to the original airspeed and the original groundspeed.
Similar effects occur in the case of a transient head-on gust. FIGS. 3B through 3E show the results of a 30 ft/sec head-on gust that is encountered for 5 seconds, as shown in FIG. 3A . As shown in FIG. 3B , the gust causes the measured airspeed to rise to 210 kts at about 7 seconds as the groundspeed decreases, as shown in FIG. 3C . In response to the increased airspeed, control system 11 commands a change in throttle position to reduce engine power in order to achieve the original airspeed. The throttle position versus time is shown in FIG. 3D , and the position is decreased from about 36 degrees just before the gust is encountered to about 22 degrees afterward at about 7 seconds, reducing engine power. The aircraft is thus decelerated to an even slower groundspeed, reaching a total decrease in groundspeed of 23 kts at about 11 seconds.
After peaking at 210 kts, the airspeed begins to decrease due to the reduction in engine power, and the airspeed falls below 200 kts at around 9.5 seconds. Simultaneously, the throttle position is ramping up to increase engine power to attain and maintain the commanded airspeed, but control system 11 causes throttle position overshoot that does not settle out until approximately 35 seconds. The longitudinal acceleration is graphed in FIG. 3E , with an initial 8 ft/sec/sec maximum deceleration followed by a 7 ft/sec/sec maximum acceleration.
The combination of the positive and negative accelerations due to the behavior of system 11 causes undesirable effects on the passengers of the aircraft. The initial deceleration caused by a sustained or transient gust is worsened by the accelerations due to the large undershoot and overshoot of the throttle position.
SUMMARY OF THE INVENTION
There is a need for an automatic control system for controlling the airspeed of aircraft that minimizes the undesirable accelerations encountered by passengers on the aircraft.
Therefore, it is an object of the present invention to provide for an automatic control system for controlling the airspeed of aircraft that minimizes the undesirable accelerations encountered by passengers on the aircraft.
A flight control system for an aircraft receives a selected value of a first parameter, which is either the airspeed or inertial velocity of the aircraft. A primary feedback loop generates a primary error signal that is proportional to the difference between the selected value and a measured value of the first parameter. A secondary feedback loop generates a secondary error signal that is proportional to the difference between the selected value of the first parameter and a measured value of a second flight parameter, which is the other of the airspeed and inertial velocity. The primary and secondary error signals are summed to produce a velocity error signal, and the velocity error signal and an integrated value of the primary error signal are summed to produce an actuator command signal. The actuator command signal is then used for operating aircraft devices to control the first parameter to minimize the primary error signal. o The present invention provides for several advantages, including: (1) reduction of unwanted longitudinal acceleration caused by automatic responses to head-on gusts and air turbulence; (2) reduction of the automatic engine power changes caused as a response to air turbulence; (3) increase of the stability for a flight control system, thus reducing the overshoots and undershoots caused by turbulence and commanded changes; and (4) improvement of the efficiency of the aircraft by reducing accelerations caused by the air turbulence.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, including its features and advantages, reference is now made to the detailed description of the invention taken in conjunction with the accompanying drawings in which like numerals identify like parts, and in which:
FIG. 1 is a schematic view of the components of a prior-art flight control system;
FIGS. 2A through 2E are graphs over time of the input and response for a sustained head-on gust using the prior-art system of FIG. 1 ;
FIGS. 3A through 3E are graphs over time of the input and response for a transient head-on gust using the prior-art system of FIG. 1 ;
FIG. 4 is a schematic view of the components of a preferred embodiment of a flight control system according to the present invention;
FIGS. 5A through 5E are graphs over time of the input and response for a sustained head-on gust using the system of FIG. 4 ;
FIGS. 6A through 6E are graphs over time of the input and response for a transient head-on gust using the system of FIG. 4 ;
FIG. 7 is a perspective view of an aircraft comprising the flight control system of FIG. 4 ;
FIG. 8 is an alternative embodiment of the flight control system of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is directed to an airspeed control system configured for automatically controlling the airspeed of an aircraft and reducing the longitudinal accelerations due to air turbulence encountered during flight. When a wind gust having a longitudinal component is detected, the system of the invention uses the combination of an airspeed signal and an inertial velocity (longitudinal ground speed) signal as the velocity feedback signal for the control system. In calm air, the steady-state airspeed and inertial velocity are the same value.
Referring to the figures, FIG. 4 shows a schematic view of a preferred embodiment of the control system of the invention in which a selected airspeed is commanded by the operator or pilot. System 23 is a closed-loop feedback system that uses both airspeed and inertial velocity (ground speed) to determine the appropriate throttle response to changes in airspeed. In the system shown, a selected airspeed signal is output from a command device 25 , which may be an onboard interface used by a pilot or a control system, such as an autopilot system. Alternatively, command device 25 may interface with a receiver that receives commands transmitted from a location remote from the aircraft, such as with an unmanned or remotely piloted vehicle. The airspeed command signal is summed at node 27 with a signal output from airspeed feedback loop 29 , which is the primary feedback loop. An airspeed sensor 31 is in data communication with airspeed feedback loop 29 for providing a signal representing the measured airspeed of the aircraft, and the negative value of the measured airspeed is summed with the commanded airspeed at node 27 to calculate an airspeed error signal. Likewise, an inertial velocity, or groundspeed, feedback loop 33 provides a signal representing a value of inertial velocity measured by an inertial velocity sensor 35 in data communication with feedback loop 33 . In this embodiment, the inertial velocity feedback loop 33 is the secondary feedback loop. The negative value of the inertial velocity measured by sensor 35 is summed with the commanded airspeed at node 37 to calculate an inertial velocity error.
The airspeed error calculated at node 27 is used in two subsequent calculations. The inertial velocity error (calculated at node 37 ) is summed with the positive value of the airspeed error at node 39 to calculate a velocity error. The integral value of airspeed error is calculated using integrator 41 , and the positive value of this integral value is summed with the positive value of the velocity error at node 43 . The output signal from node 43 represents the actuator command signal used by actuators or other devices represented by box 45 for controlling the airspeed of the aircraft such that the airspeed is minimized.
By using the combination of an airspeed signal and an inertial velocity signal as the velocity feedback signal, the dynamic combination of these two signals will reduce the amplitude of the changes commanded by system 23 caused by air turbulence were only airspeed sensor 31 used. Sensors 31 , 35 indicate velocity errors in opposite directions, but because the proportional velocity error is computed from the combination of these two signals, the undesirable acceleration is significantly less due to the cancellation effect of these two signals. However, the low-frequency, or steady-state, velocity error used for the integral of velocity error is determined by airspeed sensor 31 only, so the steady airspeed is not affected by the inertial velocity signal. The improved response can be seen in FIGS. 5A through 5E and FIGS. 6A through 6E , which are graphs showing the input and improved response for head-on gusts of the same velocity and duration as those graphed for prior-art control system 11 in FIGS. 2A through 2E and FIGS. 3A through 3E , respectively.
For example, the graph in FIG. 5A shows that a sustained 30 ft/sec head-on gust is encountered at 5 seconds on the timeline and ramps to its maximum value in approximately 1 second. The gust causes the measured airspeed, shown in FIG. 5B , to rise from the commanded airspeed of 200 kts to approximately 207 kts at around 7.5 seconds. FIG. 5C shows that groundspeed also decreases, as expected. In response to the increased airspeed, control system 23 commands a change in an actuator or other device to affect the airspeed. In this example, throttle position is used to control engine power, and the throttle position is initially reduced in order to achieve the original airspeed. However, the throttle position, as shown in FIG. 5D , is decreased from about 36 degrees just before the gust is encountered to about 30 degrees afterward at approximately 7 seconds. The throttle position then smoothly ramps up to approximately 62 degrees while the airspeed and groundspeed smoothly settle at the new values. The system settles out in approximately 15 seconds from the beginning of the gust. As shown by the graph in FIG. 5E , a reduction is also realized for the vertical accelerations and motions.
When compared to the responses of the prior-art system 11 , it should be noted that the graphs in FIGS. 5B through 5D lack the undershoot and overshoot found in the response of the prior-art system. When the system gently settles to the new values without these oscillations, passenger ride comfort is increased.
The same improvements are also seen in the responses to a transient wind gust, as shown in FIGS. 6A through 6E . A 30 ft/sec head-on gust is encountered at time=5 seconds, and the gust lasts for 5 seconds. FIG. 6B shows the measured airspeed peaks at 210 kts at around 7 seconds and undershoots to about 194 kts at around 12 seconds. The groundspeed, shown in FIG. 6C , has a maximum decrease of approximately 15 kts at approximately 10 seconds, but the groundspeed recovers after the gust without an overshoot. Referring now to FIG. 6D , the throttle position changes from an initial setting of 36 degrees to approximately 26 degrees in response to the gust, then increases to near 60 degrees to increase the airspeed after the gust has ended. The throttle position then settles back to approximately 36 degrees without undershoot. The system response settles in approximately 15 seconds from the beginning of the gust.
Comparing the response of the system of the present invention to the responses shown in FIGS. 3B through 3E for the prior-art system, it should be noted that the system of the present invention reduces the maximum deviations from the pre-gust conditions without the undershoot and overshoot seen in the responses of the prior-art system. Also, the system settles sooner than the prior-art system, and the longitudinal accelerations, graphed in FIG. 6E last for a shorter time. All of these contribute to improving the ride comfort of the passengers on the aircraft.
The devices on the aircraft used to control the airspeed may be of various types depending on the type of aircraft. For example, FIG. 7 shows a tiltrotor aircraft 47 having an airspeed control system according to the present invention. Aircraft 47 has two rotors 49 having multiple blades 51 , and each rotor 49 is rotated with torque provided from an engine carried in an associated nacelle 53 . Each nacelle 53 is pivotally mounted to the outer end of a wing 55 of aircraft 47 , allowing for each nacelle 53 to rotate between a horizontal position, as shown in the figure, and a vertical position. Each engine has means (not shown) for controlling the power output and/or speed of the engine, and these means are collectively referred to herein as a “throttle.”
While shown as a tiltrotor aircraft, it should be understood that airspeed control system 23 of the present invention is applicable to all types of aircraft, including fixed-wing aircraft and helicopters. In addition, though the engines of aircraft 47 are turbine engines, system 23 of the invention is also applicable to other types of aircraft engines, including reciprocating engines. Also, though throttles are primarily used to control the output of engines on aircraft 47 , control system 23 may be used to control other devices for controlling the amount or direction of thrust produced by rotors 49 . For example, control system 23 may be used to control the rotational position of nacelles 53 or the pitch of blades 51 . In other types of aircraft, control system 23 may be used to control airspeed through the use of thrust-vectoring devices, such as those used to direct turbine exhaust.
FIG. 8 is a schematic view of an alternative embodiment of the control system of the present invention. Control system 57 is configured for maintaining a commanded inertial velocity, or groundspeed, rather than maintaining a commanded airspeed, as was system 23 of FIG. 4 above.
System 57 is a closed-loop feedback system that uses both airspeed and inertial velocity (ground speed) to determine the appropriate throttle response to changes in inertial velocity. In the system shown, a selected inertial velocity signal is output from a command device 59 , which may be an onboard interface used by a pilot or a control system, such as an autopilot system. Alternatively, command device 59 may interface with a receiver that receives commands transmitted from a location remote from the aircraft. The inertial velocity command signal is summed at node 61 with a signal output from inertial velocity feedback loop 63 , which is the primary feedback loop in this embodiment. An inertial velocity sensor 65 is in data communication with inertial velocity feedback loop 63 for providing a signal representing the measured inertial velocity of the aircraft, and the negative value of the measured inertial velocity is summed with the commanded inertial velocity at node 61 to calculate an inertial velocity error signal. Likewise, an airspeed feedback loop 67 , which is the secondary feedback loop in this embodiment, provides a signal representing a value of airspeed measured by an airspeed sensor 69 in data communication with feedback loop 67 . The negative value of the airspeed measured by sensor 69 is summed with the commanded inertial velocity at node 71 to calculate an airspeed error.
The inertial velocity error calculated at node 61 is used in two subsequent calculations. The airspeed error (calculated at node 71 ) is summed with the positive value of the inertial velocity error at node 73 to calculate a velocity error. The integral value of the inertial velocity error is calculated using integrator 75 , and the positive value of this integral value is summed with the positive value of the velocity error at node 77 . The output signal from node 77 represents the actuator command signal used by actuators or other devices represented by box 79 for controlling the airspeed of the aircraft such that the inertial velocity error is minimized.
The combination of an airspeed signal and an inertial velocity signal as the velocity feedback signal will reduce the amplitude of the changes commanded by system 57 caused by air turbulence. When a wind gust is encountered, sensors 65 , 69 detect velocity changes in opposite directions. The proportional velocity error is computed using these two signals, so the undesirable power or thrust surge is significantly less due to the cancellation effects. However, the low frequency, or steady-state, inertial velocity error used for the integral of velocity error is determined by the inertial velocity sensor only, so the steady velocity is not affected by the airspeed signal.
For example, an aircraft using an inertial velocity control system may encounter air that is moving in the opposite direction of the aircraft. When this occurs, the inertial velocity sensor will detect a decrease in the inertial velocity due to the increased aerodynamic drag. The inertial velocity control system is commanded to maintain a constant inertial velocity, and the system will operate devices on the aircraft so as to attain and maintain the original inertial velocity.
The present invention provides for several advantages, including: (1) reduction of unwanted longitudinal acceleration caused by automatic responses to head-on gusts and air turbulence; (2) reduction of the automatic engine power changes caused as a response to air turbulence; (3) increase of the stability for a flight control system, thus reducing the overshoots and undershoots caused by turbulence and commanded changes; and (4) improvement of the efficiency of the aircraft by reducing accelerations caused by the air turbulence.
While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description. | A flight control system for an aircraft receives a selected value of a first parameter, which is either the airspeed or inertial velocity of the aircraft. A primary feedback loop generates a primary error signal that is proportional to the difference between the selected value and a measured value of the first parameter. A secondary feedback loop generates a secondary error signal that is proportional to the difference between the selected value of the first parameter and a measured value of a second flight parameter, which is the other of the airspeed and inertial velocity. The primary and secondary error signals are summed to produce a velocity error signal, and the velocity error signal and an integrated value of the primary error signal are summed to produce an actuator command signal. The actuator command signal is then used for operating aircraft devices to control the first parameter to minimize the primary error signal. | 1 |
BACKGROUND
[0001] The present invention relates generally to operations performed in conjunction with subterranean wells and, in an embodiment described herein, more particularly provides a method of forming sealed wellbore junctions.
[0002] Many systems have been developed for connecting intersecting wellbores in a well. Unfortunately, these systems typically involve methods which unduly restrict access to one or both of the intersecting wellbores, restrict the flow of fluids, are very complex or require very sophisticated equipment to perform, are time-consuming in that they require a large number of trips into the well, do not provide secure attachment between casing in the parent wellbore and a liner in the branch wellbore and/or do not provide a high degree of sealing between the intersecting wellbores.
[0003] For example, some wellbore junction systems rely on cement alone to provide a seal between the interior of the wellbore junction and a formation surrounding the junction. In these systems, there is no attachment between the casing in the parent wellbore and the liner in the branch wellbore, other than that provided by the cement. These systems are acceptable in some circumstances, but it would be desirable in other circumstances to be able to provide more secure attachment between the tubulars in the intersecting wellbores, and to provide more effective sealing between the tubulars.
SUMMARY
[0004] In carrying out the principles of the present invention, in accordance with an embodiment thereof, a method of forming a wellbore junction is provided which both securely attaches tubulars in intersecting wellbores and effectively seals between the tubulars. The method is straightforward and convenient in its performance, does not unduly restrict flow or access through the junction, and does not require an inordinate number of trips into the well.
[0005] In one aspect of the invention, a method is provided for forming a wellbore junction which includes a step of expanding a member within a tubular structure positioned at an intersection of two wellbores. This expansion of the member may perform several functions. For example, the expanded member may secure an end of a tubular string which extends into a branch wellbore. The expanded member may also seal to the tubular string and/or to the tubular structure.
[0006] In another aspect of the invention, the tubular string may be installed in the branch wellbore through a window formed through the tubular structure. An engagement device on the tubular string engages the tubular structure to secure the tubular string to the tubular structure. For example, the engagement device may be a flange which is larger in size than the window of the tubular structure and is prevented from passing therethrough, thereby fixing the position of the tubular string relative to the tubular structure.
[0007] In yet another aspect of the invention, a whipstock may be used to drill the branch wellbore through the window in the tubular structure. Thereafter, the whipstock is used to install the tubular string in the branch wellbore. After installation of the tubular string, the whipstock may be retrieved from the parent wellbore, thereby permitting full bore access through the wellbore junction in the parent wellbore. The tubular string may be installed and the whipstock retrieved in only a single trip into the well using a unique tool string.
[0008] In still another aspect of the invention, the window may be formed in the tubular structure prior to cementing the tubular structure in the parent wellbore. To prevent cement flow through the window, a retrievable sleeve is used inside the tubular structure. After cementing, the sleeve is retrieved from within the tubular structure.
[0009] Various types of seals may be used between various elements of the wellbore junction. For example metal to metal seals may be used, or elements of the wellbore junction may be adhesively bonded to each other, etc.
[0010] These and other features, advantages, benefits and objects of the present invention will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description of representative embodiments of the invention hereinbelow and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a cross-sectional view of a method of forming a wellbore junction which embodies principles of the present invention and wherein a tubular structure has been cemented within a parent wellbore;
[0012] FIG. 2 is an enlarged cross-sectional view of the method wherein a branch wellbore has been drilled through the tubular structure utilizing a whipstock positioned in the tubular structure;
[0013] FIG. 3 is a cross-sectional view of the method wherein a tubular string is being installed in the branch wellbore;
[0014] FIG. 4 is an enlarged cross-sectional view of the method wherein a sleeve is being expanded within the tubular structure to thereby secure and seal the tubular string to the tubular structure;
[0015] FIG. 5 is a cross-sectional view taken along line 5 - 5 of FIG. 4 , showing the sleeve expanded within the tubular structure;
[0016] FIGS. 6 & 7 are cross-sectional views of the sleeve in its radially compressed and expanded configurations, respectively;
[0017] FIGS. 8-13 are cross-sectional views of a second method embodying principles of the present invention;
[0018] FIGS. 14-17 are cross-sectional views of a third method embodying principles of the present invention;
[0019] FIGS. 18-20 are cross-sectional views of a fourth method embodying principles of the present invention;
[0020] FIGS. 21-25 are cross-sectional views of a fifth method embodying principles of the present invention;
[0021] FIGS. 26 & 27 are cross-sectional views of a sixth method embodying principles of the present invention;
[0022] FIGS. 28 & 29 are cross-sectional views of a seventh method embodying principles of the present invention;
[0023] FIG. 30 is a cross-sectional view of an eighth method embodying principles of the present invention; and
[0024] FIGS. 31-35 are cross-sectional views of a ninth method embodying principles of the present invention.
DETAILED DESCRIPTION
[0025] Representatively illustrated in FIG. 1 is a method 10 which embodies principles of the present invention. In the following description of the method 10 and other apparatus and methods described herein, directional terms, such as “above”, “below”, “upper”, “lower”, etc., are used only for convenience in referring to the accompanying drawings. Additionally, it is to be understood that the various embodiments of the present invention described herein may be utilized in various orientations, such as inclined, inverted, horizontal,.vertical, etc., and in various configurations, without departing from the principles of the present invention.
[0026] As depicted in FIG. 1 , several steps of the method 10 have already been performed. A parent wellbore 12 has been drilled and a tubular structure 14 has been positioned in the parent wellbore. The tubular structure 14 is part of a casing string 16 used to line the parent wellbore 12 .
[0027] It should be understood that use of the terms “parent wellbore” and “casing string” herein are not to be taken as limiting the invention to the particular illustrated elements of the method 10 . The parent wellbore 12 could be any wellbore, such as a branch of another wellbore, and does not necessarily extend directly to the earth's surface. The casing string 16 could be any type of tubular string, such as a liner string, etc. The terms “casing string” and “liner string” are used herein to indicate tubular strings of any type, such as segmented or unsegmented tubular strings, tubular strings made of any materials, including nonmetal materials, etc. Thus, the reader will appreciate that these and other descriptive terms used herein are merely for convenience in clearly explaining the illustrated embodiments of the invention, and are not used for limiting the scope of the invention.
[0028] The casing string 16 also includes two anchoring profiles 18 , 20 for purposes that are described below. The lower profile 20 may be an orienting latch profile, for example, a profile which serves to rotationally orient a device engaged therewith relative to the window 28 . The upper profile 18 may also be an orienting latch profile. Such orienting profiles are well known to those skilled in the art.
[0029] A tubular shield 22 is received within the casing string 16 , and seals 24 , 26 carried on the shield are positioned at an upper end of the tubular structure 14 and at a lower end of the anchoring profile 20 , respectively. The shield 22 is a relatively thin sleeve as depicted in FIG. 1 , but it could have other shapes and other configurations in keeping with the principles of the invention.
[0030] The shield 22 serves to prevent flow through a window 28 formed laterally through a sidewall of the tubular structure 14 . Specifically, the shield 22 prevents the flow of cement through the window 28 when the casing string 16 is cemented in the parent wellbore 12 . The shield 22 also prevents fouling of the lower profile 20 during the cementing operation, and the shield may be releasably engaged with the profile to secure it in position during the cementing operation and to enable it to be retrieved from the casing string 16 after the cementing operation, for example, by providing an appropriate convention latch on the shield.
[0031] The shield 22 prevents cement from flowing out to the window 28 when cement is pumped through the casing string 16 . Other means may be used external to the tubular structure 14 to prevent cement from flowing in to the window 28 , for example, an outer membrane, a fiberglass wrap about the tubular structure, a substance filling the window and any space between the window and the shield 22 , etc.
[0032] At this point it should be noted that the use of the terms “cement” and “cementing operation” herein are used to indicate any substance and any method of deploying that substance to fill the annular space between a tubular string and a wellbore, to seal between the tubular string and the wellbore and to secure the tubular string within the wellbore. Such substances may include, for example, various cementitious compositions, polymer compositions such as epoxies, foamed compositions, other types of materials, etc.
[0033] At the time the casing string 16 is positioned in the wellbore 12 , but prior to the cementing operation, the tubular structure 14 is rotationally oriented so that the window 28 faces in a direction of a desired branch wellbore to extend outwardly from the window. Thus, the tubular structure 14 is positioned at the future intersection between the parent wellbore 12 and the branch wellbore-to-be-drilled, with the window 28 facing in the direction of the future branch wellbore. The rotational orientation may be accomplished in any of a variety of ways, for example, by engaging a gyroscopic device with the upper profile 18 , by engaging a low side indicator with the shield 22 , etc. Such rotational orienting devices (gyroscope, low side indicator, etc.) are well known to those skilled in the art.
[0034] After the tubular structure 14 is positioned in the wellbore 12 with the window 28 facing in the proper direction, the casing string 16 is cemented in place in the wellbore. When the cementing operation is concluded, the shield 22 is retrieved from the casing string 16 .
[0035] Referring additionally now to FIG. 2 , an enlarged view of the method 10 is representatively illustrated wherein the shield 22 has been retrieved. A whipstock 30 or other type of deflection device has been installed in the tubular structure 14 by engaging keys, lugs or dogs 32 with the profile 20 , thereby releasably securing the whipstock in position and rotationally aligning an upper. deflection surface 34 with the window 28 .
[0036] The whipstock 30 also includes an inner passage 36 and a profile 38 formed internally on the passage for retrieving the whipstock. Of course, other means for retrieving the whipstock 30 could be used, for example, a washover tool, a spear, an overshot, etc.
[0037] As depicted in FIG. 2 , one or more cutting devices, such as drill bits, etc., have been deflected off of the deflection surface 34 and through the window 28 to drill a branch wellbore 40 extending outwardly from the window. As discussed above, the term “branch wellbore” should not be taken as limiting the invention, since the wellbore 40 could be a parent of another wellbore, or could be another type of wellbore, etc.
[0038] Referring additionally now to FIG. 3 , the method 10 is representatively illustrated wherein a tubular string 42 has been installed in the branch wellbore 40 . The tubular string 42 may be made up substantially of liner or any other type of tubular material.
[0039] As depicted in FIG. 3 , the tubular string 42 includes an engagement device 44 for engaging the tubular structure 14 and securing an upper end of the tubular string thereto. The tubular string 42 also includes a flex or swivel joint 46 for enabling, or at least enhancing, deflection of the tubular string from the parent wellbore 12 into the branch wellbore 40 . Alternatively, or in addition, the swivel joint 46 permits rotation of an upper portion of the tubular string 42 relative to a lower portion of the tubular string in the rotational alignment step of the method 10 described below. The tubular string 42 is deflected off of the deflection surface 34 as it is conveyed downwardly attached to a tool string 48 .
[0040] The tool string 48 includes an anchor 50 for releasable engagement with the upper profile 18 , a running tool 52 for releasable attachment to the tubular string 42 , and a retrieval tool 54 for retrieving the whipstock 30 . The running tool 52 may include keys, lugs or dogs for engaging an internal profile (not shown) of the tubular string 42 . The retrieval tool 54 may include keys, lugs or dogs for engagement with the profile 38 of the whipstock 30 .
[0041] When the anchor 50 is engaged with the profile 18 , the tubular string 42 is rotationally aligned so that the engagement device 44 will properly engage the tubular structure 14 as further described below. In addition, the anchor 50 is preferably spaced apart from the engagement device 44 so that when the anchor is engaged with the profile 18 and a shoulder 56 formed on a tubing string 58 of the tool string 48 contacts the anchor, the engagement device is properly lo positioned in engagement with the tubular structure 14 .
[0042] Specifically, the tubing string 58 is slidably received within the anchor 50 . When the shoulder 56 contacts the anchor 50 , the engagement device 44 is a predetermined distance from the anchor. This distance between the anchor 50 and the engagement device 44 corresponds with another predetermined distance between the profile 18 and the tubular structure 14 . Thus, when the tubular string 42 is being conveyed into the branch wellbore 40 , the engagement device 44 will properly engage the tubular structure 14 as the shoulder 56 contacts the anchor 50 .
[0043] The running tool 52 may then be released from the tubular string 42 , the tool string 48 may be raised into the parent wellbore 12 , and then the retrieval tool 54 may be engaged with the profile 38 in the whipstock 30 to retrieve the whipstock from the parent wellbore. Note that the installation of the tubular string 42 and the retrieval of the whipstock 30 may thus be accomplished in a single trip into the well.
[0044] The engagement device 44 is depicted in FIG. 3 as a flange which extends outwardly from the upper end of the tubular string 42 . The engagement device 44 includes a backing plate or landing plate 60 which is received in an opening 62 formed through a sidewall of a guide structure 64 of the tubular structure 14 . Preferably, the opening 62 is complementarily shaped relative to the plate 60 , and this complementary engagement maintains the alignment between the tubular string 42 and the tubular structure 14 . For example, engagement between the plate 60 and the opening 62 supports the upper end of the tubular string 42 , so that an annular space exists about the upper end of the tubular string for later placement of cement therein.
[0045] The guide structure 64 is more clearly visible in the enlarged view of FIG. 2 . In this view it may also be seen that the opening 62 includes an elongated slot 66 at a lower end thereof. Preferably, the plate 60 includes a downwardly extending tab 68 (see FIG. 3 ) which engages the slot 66 and thereby prevents rotation of the engagement device 44 relative to the window 28 .
[0046] The engagement device 44 is larger in size than the window 28 , and so the engagement device prevents the tubular string 42 from being conveyed too far into the branch wellbore 40 . The engagement device 44 thus secures the upper end of the tubular string 42 relative to the tubular structure 14 . Of course, other types of engagement devices may be used in place of the illustrated flange and backing plate, for example, an orienting profile could be formed on the tubular structure and keys, dogs or lugs could be carried on the tubular string 42 for engagement therewith to orient and secure the tubular string relative to the tubular structure.
[0047] As depicted in FIG. 3 , the engagement device 44 carries a seal 70 thereon which circumscribes the opening 62 and sealingly engages the guide structure 64 . The guide structure 64 carries seals 72 , 74 thereon which sealingly engage above and below the window 28 . Thus, the tubular string 42 is sealed to the tubular structure 14 so that leakage therebetween is prevented. The seals 70 , 72 , 74 , or any of them, may be elastomer seals, non-elastomer seals, metal to metal seals, expanding seals, and/or seals created by adhesive bonding, such as by using epoxy or another adhesive.
[0048] Referring additionally now to FIG. 4 , an enlarged view is representatively illustrated of the method 10 after the tubular string 42 is installed in the branch wellbore 40 and the whipstock 30 is retrieved from the well. Note that an alternatively constructed engagement device 44 is illustrated in FIG. 4 which does not include the plate 60 . Instead, the flange portion of the engagement device 44 is received in the opening 62 and the engagement device is sealed to the tubular structure 14 about the window 28 using one or more seals 76 , 78 , 80 circumscribing the window. The seal 76 is an adhesive, the seal 78 is an o-ring and the seal 80 is a metal to metal seal.
[0049] To further secure the tubular string 42 to the tubular structure 14 , a member 82 is expanded within the tubular structure using an expansion device 84 . As depicted in FIG. 4 , the member 82 is a tubular sleeve having an opening 86 formed through a sidewall thereof. Of course, other expandable member shapes and configurations could be used in keeping with the principles of the invention.
[0050] The opening 86 is rotationally aligned with an internal flow passage 88 of the tubular string 42 , for example, by engaging the expansion device 84 with the upper profile 18 . Then, the expansion device 84 is actuated to displace a wedge or cone go upwardly through the member 82 , thereby expanding the member outwardly. Such outward expansion also outwardly displaces seals 92 , 94 , 96 , 98 , 100 carried on the member.
[0051] The seals 94 , 96 sealingly engage the guide structure 64 above and below the opening 62 . The seals 92 , 98 are metal to metal seals and sealingly engage the tubular structure 14 above and below the guide structure 64 . The seal 100 is an adhesive seal which circumscribes the passage 88 and sealingly engages the flange portion of the engagement device 44 . Of course, the seals 92 , 94 , 96 , 98 , 100 , or any of them, may be any type of seal, for example, elastomer, non-elastomer, metal to metal, adhesive, etc.
[0052] After the member 82 is expanded, the expansion device 84 is retrieved from the well and the tubular string 42 is cemented within the branch wellbore 40 . For example, a foamed composition may be injected into the annulus radially between the tubular string 42 and the branch wellbore 40 . The foamed composition could expand in the annulus to fill any voids therein, and could expand to fill any voids about the structure 14 in the wellbore 12 .
[0053] Note that the engagement device 44 is retained between the member 82 and the tubular structure 14 , thereby preventing upward and downward displacement of the tubular string 42 . In addition, where metal to metal seals are used, the expansion of the member 82 maintains a biasing force on these seals to maintain sealing engagement.
[0054] Referring additionally now to FIG. 5 , a partial cross-sectional view, taken along line 5 - 5 of FIG. 4 is representatively illustrated. In this view, only the tubular string 42 , tubular structure 14 , guide structure 64 and expandable member 82 cross-sections are shown for clarity of illustration. From FIG. 5 , it may be more clearly appreciated how the engagement device 44 is received in the guide structure 64 , and how expansion of the member 82 secures the engagement device in the tubular structure 14 .
[0055] In addition, note that no separate seals are visible in FIG. 5 for sealing between the engagement device 44 and the tubular structure 14 or expansion member 82 . This is due to the fact that FIG. 5 illustrates an alternate sealing method wherein sealing between the engagement device 44 and each of the tubular structure 14 and expansion member 82 is accomplished by metal to metal contact between these elements.
[0056] Specifically, expansion of the member 82 causes it to press against an interior surface the engagement device 44 circumscribing the passage 88 , which in turn causes an exterior surface of the engagement device to press against an interior surface of the tubular structure 14 circumscribing the window 28 . This pressing of one element surface against another when the member 82 is expanded results in metal to metal seals being formed between the surfaces. However, as mentioned above, any type of seal may be used in keeping with the principles of the invention.
[0057] Referring additionally now to FIGS. 6 and 7 , the expansion member 82 is representatively illustrated in its radially compressed and radially expanded configurations, respectively. In FIG. 6 , it may be seen that the expansion member 82 in its radially compressed configuration has a circumferentially corrugated shape, that is, the member has a convoluted shape about its circumference. In FIG. 7 , the member 82 is radially expanded so that it attains a substantially cylindrical tubular shape, that is, it has a substantially circular cross-sectional shape.
[0058] Referring additionally now to FIGS. 8-13 , another method lo embodying principles of the invention is representatively illustrated. In the method 110 , a tubular structure 112 is interconnected in a casing string 114 and conveyed into a parent wellbore 116 . The tubular structure 112 preferably includes a tubular outer shield 118 outwardly overlying a window 120 formed through a sidewall of the tubular structure. The shield 118 is preferably made of a relatively easily drilled or milled material, such as aluminum.
[0059] The shield 118 prevents cement from flowing outwardly through the window 120 when the casing string 114 is cemented in the wellbore 116 . The shield 118 also transmits torque through the tubular structure 112 from above to below the window 120 , due to the fact that the shield is rotationally secured to the tubular structure above and below the window, for example, by castellated engagement between upper and lower ends of the shield and the tubular structure above and below the window, respectively.
[0060] The tubular structure 112 is rotationally aligned with a branch wellbore-to-be-drilled 122 , so that the window 120 faces in the radial direction of the desired branch wellbore. This rotational alignment may be accomplished, for example, by use of a conventional wireline-conveyed direction sensing tool (not shown) engaged with a key or keyway 124 having a known orientation relative to the window 120 . Other rotational alignment means may be used in keeping with the principles of the invention.
[0061] In FIG. 9 it may be seen that a work string 126 is used to convey a mill, drill or other cutting tool 128 , a whipstock or other deflection device 130 and an orienting latch or anchor 132 into the casing string 114 . The drill 128 is releasably attached to the whipstock 130 , for example, by a shear bolt 134 , thereby enabling the drill and whipstock to be conveyed into the casing string 114 in a single trip into the well.
[0062] The anchor 132 is engaged with an anchoring and orienting profile 136 in the casing string 114 below the tubular structure 112 . Such engagement secures the whipstock 130 relative to the tubular structure 112 and rotationally orients the whipstock relative to the tubular structure, so that an upper inclined deflection surface 138 of the whipstock faces toward the window 120 and the desired branch wellbore 122 .
[0063] Thereafter, the shear bolt 134 is sheared (for example, by slacking off on the work string 126 , thereby applying a downwardly directed force to the bolt), permitting the drill 128 to be laterally deflected off of the surface 138 and through the window 120 . The drill 128 is used to drill or mill outwardly through the shield 118 , and to drill the branch wellbore 122 . Of course, multiple cutting tools and different types of cutting tools may be used for the drill 128 during this driling process.
[0064] As depicted in FIG. 9 , the casing string 114 has been cemented within the wellbore 116 prior to the drilling process. However, it is to be clearly understood that it is not necessary for the tubular structure 112 to be cemented in the wellbore 116 at this time. It may be desirable to delay cementing of the casing string 114 , or to forego cementing of the tubular structure 112 , as set forth in further detail below.
[0065] In FIG. 10 it may be seen that the branch wellbore 122 has been drilled extending outwardly from the window 120 of the tubular structure 112 by laterally deflecting one or more cutting tools from the parent wellbore 116 off of the deflection surface 138 of the whipstock 130 .
[0066] In FIG. 11 it may be seen that a liner string 140 is conveyed through the casing string 114 , and a lower end of the liner string is laterally deflected off of the surface 138 , through the window 120 , and into the branch wellbore 122 . An engagement device 142 attached at an upper end of the liner string 140 engages a tubular guide structure 144 of the tubular structure 112 , thereby securing the upper end of the liner string to the tubular structure. This engagement between the device 142 and the structure 112 forms a load-bearing connection between the casing string 114 and the liner string 140 , so that further displacement of the liner string into the branch wellbore 122 is prevented.
[0067] Engagement between the device 142 and the structure 144 may also rotationally secure the device relative to the tubular structure 112 . For example, the slot 66 and tab 68 described above may be used on the device 142 and structure 144 , respectively, to prevent rotation of the device in the tubular structure 112 . Other types of complementary engagement, and other means of rotationally securing the device 142 relative to the tubular structure 112 may be used in keeping with the principles of the invention.
[0068] Note that the device 142 is depicted in FIG. 11 as a radially outwardly extending flange-shaped member which inwardly overlaps the perimeter of the window 120 . The device 142 inwardly circumscribes the window 120 and overlaps its perimeter, so if one or both mating surfaces of the device and tubular structure 112 are provided with a suitable layer of sealing material (such as an elastomer, adhesive, relatively soft metal, etc.), a seal 146 may be formed between the device and the tubular structure due to the contact therebetween. The device 142 may be otherwise shaped, and may be otherwise sealed to the tubular structure 112 in keeping with the principles of the invention.
[0069] In FIG. 12 it may be seen that the whipstock 130 and anchor 132 are retrieved from the well and a generally tubular expandable member 148 is conveyed into the tubular structure 112 and expanded therein. For example, the expandable member 148 may be expanded radially outward using the expansion device 84 , from a radially compressed configuration (such as that depicted in FIG. 6 ) to a radially extended configuration (such as that depicted in FIG. 7 ).
[0070] The member 148 preferably has an opening 150 formed through a sidewall thereof when it is conveyed into the structure 112 . In that case, the opening 150 is preferably rotationally aligned with the window 120 (and thus rotationally aligned with an internal flow passage 152 of the liner string 140 ) prior to the member 148 being radially expanded. Alternatively, the member 148 could be conveyed into the structure 112 without the opening 150 having previously been formed, then expanded, and then a whipstock or other deflection device could be used to direct a cutting tool to form the opening through the sidewall of the member.
[0071] Note that the method 110 is illustrated in FIG. 12 as though the casing string 114 is cemented in the wellbore 116 at the time the member 148 is expanded in the structure 112 . However, the structure 112 could be cemented in the wellbore 116 after the member 148 is expanded therein.
[0072] After being expanded radially outward, the member 148 preferably has an internal diameter D 1 which is substantially equal to, or at least as great as, an internal diameter D 2 of the casing string 114 above the structure 112 . Thus, the member 148 does not obstruct flow or access through the structure 112 .
[0073] Note that a separate seal is not depicted in FIG. 12 between the member 148 and the device 142 or the structure 112 . Instead, seals 154 , 156 between the member 148 and the structure 112 above and below the guide structure 144 are formed by contact between the member 148 and the structure 112 when the member is expanded radially outward. For example, one or both mating surfaces of the member 148 and tubular structure 112 may be provided with a suitable layer of sealing material (such as an elastomer, adhesive, relatively soft metal, etc.), so that the seals 154 , 156 are formed between the member and the tubular structure due to the contact therebetween. The member 148 may be otherwise sealed to the tubular structure 112 in keeping with the principles of the invention.
[0074] To enhance sealing contact between the member 148 and the structure 112 and/or to ensure sufficient forming of the internal diameter D 1 , the structure may be expanded radially outward somewhat at the time the member is expanded radially outward, for example, by the expansion device 84 . This technique may produce some outward elastic deformation in the structure 112 , so that after the expansion process the structure will be biased radially inward to increase the surface contact pressure between the structure and the member 148 . Such an expansion technique may be particularly useful where it is desired for the seals 154 , 156 to be metal to metal seals. If this expansion technique is used, it may be desirable to delay cementing the structure 112 in the wellbore 116 until after the expansion process is completed.
[0075] Similarly, a seal 158 between the member 148 and the device 142 outwardly circumscribing the opening 150 is formed by contact between the member 148 and the device when the member is expanded radially outward. For example, one or both mating surfaces of the member 148 and device 142 may be provided with a suitable layer of sealing material (such as an elastomer, adhesive, relatively soft metal, etc.), so that the seal 158 is formed between the member and the device due to the contact therebetween. The member 148 may be otherwise sealed to the device 142 in keeping with the principles of the invention. Radially outward deformation of the structure 112 at the time the member 148 is expanded radially outward (as described above) may also enhance sealing contact between the member and the device 142 , particularly where the seal 158 is a metal to metal seal.
[0076] The expandable member 148 secures the device 142 in its engagement with the guide structure 144 . It will be readily appreciated that inward displacement of the device 142 is not permitted after the member 148 has been expanded. Furthermore, in the event that the device 142 has not yet fully engaged the guide structure 144 at the time the member 148 is expanded (for example, the device could be somewhat inwardly disposed relative to the guide structure), expansion of the member will ensure that the device is fully engaged with the guide structure (for example, by outwardly displacing the device somewhat).
[0077] Referring additionally now to FIG. 13 , an alternate procedure for use in the method 110 is representatively illustrated. This alternate procedure may be compared to the illustration provided in FIG. 8 . Instead of the outer shield 118 , the procedure illustrated in FIG. 13 uses an inner generally tubular shield 160 having an inclined upper surface or muleshoe 162 . Although no separate seals are shown in FIG. 13 , the inner shield 160 is preferably sealed to the tubular structure 112 above and below the guide structure 144 , so that cement or debris in the casing string 114 is not permitted to flow into the window 120 from the interior of the structure 112 . Preferably, the inner shield 160 is made of metal and is retrievabie from within the structure 112 after the cementing process.
[0078] To prevent cement or debris from flowing into the structure 112 through the window 120 , a generally tubular outer shield 164 outwardly overlies the window. Preferably, the outer shield 164 is made of a relatively easily drillable material, such as a composite material (e.g., fiberglass, etc.). A fluid 166 having a relatively high viscosity is contained between the inner and outer shields 162 , 164 to provide support for the outer shield against external pressure, and to aid in preventing leakage of external fluids into the area between the shields. A suitable fluid for use as the fluid 166 is known by the trade name Glcogel.
[0079] The muleshoe 162 provides a convenient surface for engagement by a conventional wireline-conveyed orienting tool (not shown). Such a tool may be engaged with the muleshoe 162 and used to rotationally orient the structure 112 relative to the branch wellbore-to-be-drilled 122 , since the muleshoe has a known radial orientation relative to the window 120 .
[0080] After the structure 112 has been appropriately rotationally oriented, the casing string 114 may be cemented in the wellbore 116 , and the inner shield 160 may then be retrieved from the well. After retrieval of the inner shield 160 , the method 110 may proceed as described above, i.e., the whipstock 130 and anchor 132 may be installed, etc. Alternatively, the inner shield 16 o may be retrieved prior to cementing the structure 112 in the wellbore 116 .
[0081] Referring additionally now to FIGS. 14-17 , another method 170 embodying principles of the invention is representatively illustrated. The method 170 differs from the other methods described above in substantial part in that a specially constructed tubular structure is not necessarily used in a casing string 172 to provide a window through a sidewall of the string. Instead, a window 176 is formed through a sidewall of the casing string 172 using conventional means, such as by use of a conventional whipstock (not shown) anchored and oriented in the casing string according to conventional practice.
[0082] One of the many benefits of the method 170 is that it may be used in existing wells wherein casing has already been installed. Furthermore, the method 170 may even be performed in wells in which the window 176 has already been formed in the casing string 172 . However, it is to be clearly understood that it is not necessary for the method 170 to be performed in a well wherein existing casing has already been cemented in place. The method 170 may be performed in newly drilled or previously uncased wells, and in wells in which the casing has not yet been cemented in place.
[0083] In FIG. 15 it may be seen that a liner string 178 is conveyed into a branch wellbore 180 which has been drilled extending outwardly from the window 176 . At its upper end, the liner string 178 includes an engagement device 182 which engages the interior of the casing string 172 and prevents further displacement of the liner string 178 into the branch wellbore 180 . Engagement of the device 182 with the casing string 172 may also rotationally align the device with respect to the casing string.
[0084] As depicted in FIG. 15 , the device 182 is a flange extending outwardly from the remainder of the liner string 178 . The device 182 inwardly overlies the perimeter of the window 176 and circumscribes the window. Contact between an outer surface of the device 182 and an inner surface of the casing string 172 may be used to provide a seal 184 therebetween, for example, if one or both of the inner and outer surfaces is provided with a layer of a suitable sealing material, such as an elastomer, adhesive or a relatively soft metal, etc. Thus, the seal 184 may be a metal to metal seal. Other types of seals may be used in keeping with the principles of the invention.
[0085] In an optional procedure of the method 170 , the liner string 178 (or at least the device 182 ) may be in a radially compressed configuration (such as that depicted in FIG. 6 ) when it is initially installed in the branch wellbore 180 , and then extended to a radially expanded configuration (such as that depicted in FIG. 7 ) thereafter. This expansion of the liner string 178 , or at least expansion of the device 182 , may be used to bring the device into sealing contact with the casing string 172 .
[0086] In FIG. 16 it may be seen that a generally tubular expandable member 186 is conveyed into the casing string 172 and aligned longitudinally with the device 182 . The member 186 has an opening 188 formed through a sidewall thereof. The opening 188 is rotationally aligned with the window 176 (and thus aligned with a flow passage 190 of the liner string 178 ).
[0087] However, it is not necessary for the opening 188 to be formed in the member 186 prior to conveying the member into the well, or for the opening to be aligned with the window 176 at the time it is positioned opposite the device 182 . For example, the opening 188 could be formed after the member 186 is installed in the casing string 172 , such as by using a whipstock or other deflection device to direct a cutting tool to cut the opening laterally through the sidewall of the member.
[0088] As depicted in FIG. 16 , the member 186 has an outer layer of a suitable sealing material 192 thereon. The sealing material 192 may be any type of material which may be used to form a seal between surfaces brought into contact with each other. For example, the sealing material 192 may be an elastomer, adhesive or relatively soft metal, etc. Other types of seals may be used in keeping with the principles of the invention.
[0089] In FIG. 17 it may be seen that the member 186 is expanded radially outward, so that it now contacts the interior of the casing string 172 and the device 182 . Preferably, such contact results in sealing engagement between the member 186 and the interior surface of the casing string 172 , and between the member and the device 182 .
[0090] Specifically, the sealing material 192 seals between the member 186 and the casing string 172 above, below and circumscribing the device 182 . The sealing material 192 also seals between the member 186 and the device 182 around the outer periphery of the opening 188 , that is, sealing engagement between the device 182 and the member 186 circumscribes the opening 188 . Thus, the interiors of the casing and liner strings 172 , 178 are completely isolated from the wellbores 174 , 180 external to the strings. This substantial benefit of the method 170 is also provided by the other methods described herein.
[0091] As depicted in FIG. 17 , the casing string 172 is outwardly deformed when the member 186 is radially outwardly expanded therein. At least some elastic deformation, and possibly some plastic deformation, of the casing string 172 outwardly overlying the member 186 is experienced, thereby recessing the member into the interior wall of the casing string.
[0092] As a result, the inner diameter D 3 of the member 186 is substantially equal to, or at least as great as, the inner diameter D 4 of the casing string 172 above the window 176 . Preferably, during the expansion process, the inner diameter D 3 of the member 186 is enlarged until it is greater than the inner diameter D 4 of the casing string 172 , so that after the expansion force is removed, the diameter D 3 will relax to a dimension no less than the diameter D 4 .
[0093] Thus, the method 170 does not result in substantial restriction of flow or access through the casing string 172 . This substantial benefit of the method 170 is also provided by other methods described herein.
[0094] Outward elastic deformation of the casing string 172 in the portions thereof overlying the member 186 is desirable in that it inwardly biases the casing string, increasing the contact pressure between the mating surfaces of the member and the casing string, thereby enhancing the seal therebetween, after the member has been expanded. However, it is to be clearly understood that it is not necessary, in keeping with the principles of the invention, for the casing string 172 to be outwardly deformed, since the member 186 may be expanded radially outward into sealing contact with the interior surface of the casing string without deforming the casing string at all.
[0095] When the member 186 is expanded, it also outwardly displaces the device 182 . This outward displacement of the device 182 further outwardly deforms the casing string 172 where it overlies the device. Elastic deformation of the casing string 172 overlying the device 182 is desirable in that it results in inward biasing of the casing string when the expansion force is removed. This enhances the seal 184 between the device 182 and the casing string 172 , and further increases the contact pressure on the sealing material between the device 182 and the member 186 .
[0096] The method 170 is depicted in FIG. 17 as though the casing string 172 is not yet cemented in the parent wellbore 174 at the time the member 186 is expanded therein. This alternate order of steps in the method 170 may be desirable in that it may facilitate outward deformation of the casing string 172 above and below the window 176 . The casing and/or liner strings 172 , 178 may be cemented in the respective wellbores 174 , 180 after the member 186 is expanded.
[0097] Referring additionally now to FIGS. 18-20 , another method 200 embodying principles of the invention is representatively illustrated. In FIG. 18 it may be seen that a tubular structure 202 is cemented in a parent wellbore 204 at an intersection with a branch wellbore 206 . However, it is not necessary for the tubular structure 202 to be cemented in the wellbore 204 until later in the method 200 , if at all.
[0098] The structure 202 is interconnected in a casing string 208 . The casing string 208 is rotationally oriented in the wellbore 204 so that a window 210 formed through a sidewall of the structure 202 is aligned with the branch wellbore 206 . Note that the window may be formed through the sidewall of the structure 202 , and that the branch wellbore 206 may be drilled, either before or after the structure is conveyed into the wellbore 204 .
[0099] A liner string 212 is conveyed into the branch wellbore 206 in a radially compressed configuration. Even though it is radially compressed, a flange-shaped engagement device 214 at an upper end of the liner string 212 is larger than the window 210 , and so the device prevents further displacement of the liner string into the wellbore 206 . Preferably, this engagement between the device 214 and the structure 202 is sufficiently load-bearing so that it may support the liner string 212 in the wellbore 206 .
[0100] An annular space 216 is provided radially between the device 214 and an opening 218 formed through the sidewall of a guide structure 220 . When the liner string 212 is expanded, the device 214 deforms radially outwardly into the annular space 216 . The liner string 212 is shown in its expanded configuration in FIG. 19 .
[0101] As depicted in FIG. 20 , a generally tubular expandable member 222 is radially outwardly expanded within the structure 202 . An opening 224 formed through a sidewall of the member 222 is rotationally aligned with a flow passage of the liner string 212 . The opening 224 may be formed before or after the member 222 is expanded.
[0102] Preferably, this expansion of the member 222 seals between the outer surface of the member and the inner surface of the structure 202 above and below the guide structure 220 , and seals between the member and the device 214 . Thus, the interiors of the casing and liner strings 208 , 212 are isolated from the wellbores 204 , 206 external to the strings. Alternatively, or in addition, a seal may be formed between the device 214 and the structure 202 circumscribing the window 210 where the structure outwardly overlies the device.
[0103] Preferably the seals obtained by expansion of the member 222 are due to surface contact between elements, at least one of which is displaced in the expansion process. For example, one of both of the member 222 and structure 202 may have a layer of sealing material (e.g., a layer of elastomer, adhesive, or soft metal, etc.) thereon which is brought into contact with the other element when the member is expanded. Metal to metal seals are preferred, although other types of seals may be used in keeping with the principles of the invention.
[0104] As depicted in FIG. 20 , the tubular structure 202 , and the casing string 208 somewhat above and below the structure, are radially outwardly expanded when the member 222 is expanded. This optional step in the method 200 may be desirable to enhance access and/or flow through the structure 202 , enhance sealing contact between any of the member 222 , device 214 , structure 202 , etc. If the casing string 208 is outwardly deformed in the method 200 , it may be desirable to cement the casing string in the wellbore 204 after the expansion process is completed.
[0105] Referring additionally now to FIGS. 21-25 another method 230 embodying principles of the invention is representatively illustrated. As depicted in FIG. 21 , an expandable liner string 232 is conveyed through a casing string 234 positioned in a parent wellbore 236 . A lower end of the liner string 232 is deflected laterally through a window 237 formed through a sidewall of a tubular structure 238 interconnected in the casing string 234 , and into a branch wellbore 240 extending outwardly from the window.
[0106] An expandable liner hanger 242 is connected at an upper end of the liner string 232 . The liner hanger 242 is positioned within the casing string 234 above the window 237 .
[0107] The liner string 232 is then expanded radially outward as depicted in FIG. 22 . As a result of this expansion process, the liner hanger 242 sealingly engages between the liner string 232 and the casing string 234 , and anchors the liner string relative to the casing string. Another result of the expansion process is that a seal is formed between the liner string and the window 237 of the structure 238 . Thus, the interiors of the casing and liner strings 232 , 234 are isolated from the wellbores 236 , 240 external to the strings. The seal formed between the liner string 232 and the window 237 is preferably a metal to metal seal, although other types of seals may be used in keeping with the principles of the invention.
[0108] A portion 244 of the liner string 232 extends laterally across the interior of the casing string 234 above a deflection device 246 positioned below the window 237 . As depicted in FIG. 23 , a milling or drilling guide 248 is used to guide a drill, mill or other cutting tool 250 to cut through the sidewall of the liner string 232 at the portion 244 above the deflection device 246 . In this manner, access and flow between the casing string 234 above and below the liner portion. 244 through an internal flow passage 252 of the deflection device 246 is provided.
[0109] Alternatively, the liner portion 244 may have an opening 254 formed therethrough. The opening 254 may be formed, for example, by waterjet cutting through the sidewall of the liner string 232 . The opening 254 may be formed before or after the liner string 232 is conveyed into the well.
[0110] Preferably, the opening 254 is formed with a configuration such that it has multiple flaps or inward projections 256 which may be folded to increase the inner dimension of the opening, e.g., to enlarge the opening for enhanced access and flow therethrough. As depicted in FIG. 25 , the projections 256 are folded over by use of a drift or punch 258 , thereby enlarging the opening 254 through the liner portion 244 .
[0111] The projections 256 are thus displaced into the passage 252 of the deflection device 246 below the liner string 232 . A seal may be formed between the liner portion 244 and the deflection device 246 circumscribing the opening 254 in this process of deforming the projections 256 downward into the passage 252 . Preferably, the seal is due to metal to metal contact between the liner portion 244 and the deflection device 246 , but other types of seals may be used in keeping with the principles of the invention.
[0112] Referring additionally now to FIGS. 26 & 27 , another method 260 of sealing and securing a liner string 262 in a branch wellbore to a tubular structure 264 interconnected in a casing string in a parent wellbore is representatively illustrated. Only the structure 264 and liner string 262 are shown in FIG. 26 for illustrative clarity.
[0113] In FIG. 26 it may be seen that the liner string 262 is positioned so that it extends outwardly through a window 266 formed through a sidewall of the structure 264 . The liner string 262 would, for example, extend into a branch wellbore intersecting the parent wellbore in which the structure 264 is positioned.
[0114] An upper end 268 of the liner string 262 remains within the tubular structure 264 . To secure the liner string 262 in this position, a packer or other anchoring device interconnected in the liner string may be set in the branch wellbore, or a lower end of the liner string may rest against a lower end of the branch wellbore, etc. Any method of securing the liner string 262 in this position may be used in keeping with the principles of the invention.
[0115] As depicted in FIG. 26 , the upper end 268 is formed so that it is parallel with a longitudinal axis of the structure 264 . The upper end 268 may be formed in this manner prior to conveying the liner string 262 into the well, or the upper end may be formed after the liner string is positioned as shown in FIG. 26 , for example, by milling an upper portion of the liner string after it is secured in position. If the upper end 268 is formed prior to conveying the liner string 262 into the well, then the upper end may be rotationally oriented relative to the structure 264 prior to securing the liner string 262 in the position shown in FIG. 26 .
[0116] In FIG. 27 it may be seen that the upper end 268 of the liner string 262 is deformed radially outward so that it is received in an opening 270 formed through the sidewall of a generally tubular guide structure 272 in the tubular structure 264 . The opening 270 is rotationally aligned with the window 266 .
[0117] The upper end 268 is deformed outward by means of a mandrel 274 which is conveyed into the structure 264 and deflected laterally toward the upper end of the liner string 262 by a deflection device 276 . The mandrel 274 shapes the upper end 268 so that it becomes an outwardly extending flange which overlaps the interior of the structure 264 circumscribing the window 266 , that is, the flange-shaped upper end 268 inwardly overlies the perimeter of the window.
[0118] Preferably, a seal is formed between the flange-shaped upper end 268 and the interior surface of the structure 264 circumscribing the window 266 . This seal may be a metal to metal seal, may be formed by a layer of sealing material on one or both of the upper end 268 and the structure 264 , etc. Any type of seal may be used in keeping with the principles of the invention.
[0119] The flange-shaped upper end 268 also secures the liner string 262 to the structure 264 in that it prevents further outward displacement of the liner string through the window 266 . After the deforming process is completed, the mandrel 274 and deflection device 276 may be retrieved from within the structure 264 and a generally tubular expandable member (not shown) may be positioned in the structure and expanded therein. For example, any of the expandable members 82 , 148 , 186 , 222 described above may be used.
[0120] After expansion of the member in the structure 264 , the member further secures the liner string 262 relative to the structure by preventing inward displacement of the liner string through the window 266 . Various seals may also be formed between the expanded member and the structure 264 , the flange-shaped upper end 268 , and/or the guide structure 272 , etc. as described above. Any types of seals may be used in keeping with the principles of the invention.
[0121] Referring additionally now to FIGS. 28 & 29 , another method 280 of sealing and securing a liner string 282 in a branch wellbore to a tubular structure 284 interconnected in a casing string in a parent wellbore is representatively illustrated. In FIG. 28 a generally tubular expandable member 286 used in the method 280 is shown. The member 286 has a specially configured opening 288 formed through a sidewall thereof. The opening 288 may be formed, for example, by waterjet cutting, either before or after it is conveyed into the well.
[0122] The configuration of the opening 288 provides multiple inwardly extending flaps or projections 290 which may be folded to enlarge the opening. As depicted in FIG. 29 , the opening 288 has been enlarged by folding the projections 290 outward into the interior of the upper end of the liner string 282 . The projections 290 are deformed outward, for example, by a mandrel and deflection device such as the mandrel 274 and deflection device 276 described above, but any means of deforming the projections into the liner string 282 may be used in keeping with the principles of the invention.
[0123] The projections 290 are deformed outward after the member 286 is positioned within the structure 284 , the opening 288 is rotationally aligned with a window 292 formed through a sidewall of the structure, and the member is expanded radially outward. Of course, if the opening 288 is formed after the member 286 is expanded in the structure 284 , then the rotational alignment step occurs when the opening is formed.
[0124] Expansion of the member 286 secures an upper flange-shaped engagement device 294 relative to the structure 284 . Seals may be formed between the member 286 , structure 284 , engagement device 294 and/or a guide structure 296 , etc. as described above. Any types of seals may be used in keeping with the principles of the invention.
[0125] Furthermore, deformation of the projections 290 into the liner string 282 may also form a seal between the member 286 and the liner string about the opening 288 . For example, a metal to metal seal may be formed by contact between an exterior surface of the member 286 and an interior surface of the liner string 282 when the projections 290 are deformed into the liner string. Other types of seals may be used in keeping with the principles of the invention.
[0126] Preferably, the projections 290 are deformed into an enlarged inner diameter D 5 of the liner string 282 . This prevents the projections 290 from unduly obstructing flow and access through an inner passage 298 of the liner string 282 .
[0127] Referring additionally now to FIG. 30 , another method 300 of sealing and securing a liner string 302 in a branch wellbore to a tubular structure 304 interconnected in a casing string in a parent wellbore is representatively illustrated. The method 300 is similar to the method 280 in that it uses an expandable tubular member, such as the member 286 having a specially configured opening 288 formed through its sidewall. However, in the method 300 , the member 286 is positioned and expanded radially outward within the structure 304 prior to installing the liner string 302 in the branch wellbore through a window 306 formed through a sidewall of the structure.
[0128] Expansion of the member 286 within the structure 304 preferably forms a seal between the outer surface of the member and the inner surface of the structure, at least circumscribing the window 306 , and above and below the window. The seal is preferably a metal to metal seal, but other types of seals may be used in keeping with the principles of the invention.
[0129] After the member 286 has been expanded within the structure 304 , the projections 290 are deformed outward through the window 306 . This outward deformation of the projections 290 may result in a seal being formed between the inner surface of the window 306 and the outer surface of the member 286 circumscribing the opening 288 . Preferably the seal is a metal to metal seal, but any type of seal may be used in keeping with the principles of the invention.
[0130] After the projections 290 are deformed outward through the window 306 , the liner string 302 is conveyed into the well and its lower end is deflected through the window 306 and the opening 288 , and into the branch wellbore. The vast majority of the liner string 302 has an outer diameter D 6 which is less than an inner diameter D 7 through the opening 288 and, therefore, passes through the opening with some clearance therebetween. However, an upper portion 308 of the liner string 302 has an outer diameter D 8 which is preferably at least as great as the inner diameter D 7 of the opening 288 . If the diameter D 8 is greater than the diameter D 7 , some additional downward force may be needed to push the upper portion 308 of the liner string 302 through the opening 288 . In this case, the liner upper portion 308 may further outwardly deform the projections 290 , thereby enlarging the opening 288 , as it is pushed through the opening.
[0131] Contact between the outer surface of the liner upper portion 308 and the inner surface of the opening 288 may cause a seal to be formed therebetween circumscribing the opening. Preferably, the seal is a metal to metal seal, but other seals may be used in keeping with the principles of the invention. An upper end 310 of the liner string 302 may be cut off as shown in FIG. 30 , so that it does not obstruct flow or access through the structure 304 . Alternatively, the upper end 310 may be -formed prior to conveying the liner string 302 into the well.
[0132] Referring additionally now to FIGS. 31-35 , another method 320 embodying principles of the invention is representatively illustrated. In FIG. 31 it may be seen that a liner string 322 is conveyed through a casing string 324 in a parent wellbore 326 , and a lower end of the liner string is deflected laterally through a window 330 formed through a sidewall of the casing string, and into a branch wellbore 328 . The casing string 324 may or may not be cemented in the parent wellbore 326 at the time the liner string 322 is installed in the method 320 .
[0133] The liner string 322 includes a portion 332 which has an opening 334 formed through a sidewall thereof. In addition, an external layer of sealing material 336 is disposed on the liner portion 332 . The sealing material 336 may be, for example, an elastomer, an adhesive, a relatively soft metal, or any other type of sealing material. Preferably, the sealing material 336 outwardly circumscribes the opening 334 and extends circumferentially about the liner portion 332 above and below the opening.
[0134] The liner string 322 is positioned as depicted in FIG. 31 , with the liner portion 332 extending laterally across the interior of the casing string 324 and the opening 334 facing downward. However, it is to be clearly understood that it is not necessary for the opening 334 to exist in the liner portion 332 prior to the liner string 322 being conveyed into the well. Instead, the opening 334 could be formed downhole, for example, by using a cutting tool and guide, such as the cutting tool 250 and guide 248 described above. As another alternative, the opening 334 may be specially configured (such as the opening 254 depicted in FIG. 24 ), and then enlarged (as depicted for the opening 254 in FIG. 25 ).
[0135] In FIG. 32 it may be seen that the liner string 322 is expanded radially outward. Preferably, at least the liner portion 332 is expanded, but the remainder of the liner string 322 may also be expanded. Due to expansion of the liner portion 332 , the outer surface of the liner portion contacts and seals against the inner surface of the window 330 circumscribing the window. The seal between the liner portion 332 and the window 330 is facilitated by the sealing material 336 contacting the inner surface of the window. However, the seal could be formed by other means, such as metal to metal contact between the liner portion 332 and the window 330 , without use of the sealing material 336 , in keeping with the principles of the invention.
[0136] In FIG. 33 it may be seen that the opening 334 is expanded to provide enhanced flow and access between the interior of the casing string 324 below the window 330 and the interior of the liner string 322 above the window. Expansion of the opening 334 also results in a seal being formed between the exterior surface of the liner portion 332 circumscribing the opening 334 and the interior of the casing string 324 . At this point, it will be readily appreciated that the interiors of the casing and liner strings 324 , 322 are isolated from the wellbores 326 , 328 external to the strings.
[0137] Additional steps in the method 320 may be used to further seal and secure the connection between the liner and casing strings 322 , 324 . In FIG. 34 it may be seen that the liner string 322 within the casing string 324 is further outwardly expanded so that it contacts and radially outwardly deforms the casing string. The opening 334 is also further expanded, and a portion 338 of the liner string 322 may be deformed downwardly into the casing string 324 as the opening is expanded.
[0138] This further expansion of the liner string 322 , including the opening 334 , in the casing string 324 produces several desirable benefits. The liner string 322 is recessed into the inside wall of the casing string 324 , thereby providing an inner diameter D 9 in the liner string which is preferably substantially equal to, or at least as great as, an inner diameter D 10 of the casing string 324 above the window 330 . The seal between the outer surface of the liner string 322 circumscribing the opening 334 and the inner surface of the casing string 324 is enhanced by increased contact pressure therebetween. In addition, another seal may be formed between the outer surface of the liner string 322 and the inner surface of the casing string 324 above the window 330 . Furthermore, the downward deformation of the portion 338 into the casing string 324 below the window 330 enhances the securement of the liner string 322 to the casing string. As described above, outward elastic deformation of the casing string 324 may be desirable to induce an inwardly biasing force on the casing string when the expansion force is removed, thereby maintaining a relatively high level of contact pressure between the casing and liner strings 324 , 322 .
[0139] In FIG. 35 it may be seen that a generally tubular expandable member 340 having an opening 342 formed through a sidewall thereof is positioned within the casing string 324 with the opening 342 rotationally aligned with the window 330 and, thus, with a flow passage 344 of the liner string 322 . The member 340 extends above and below the liner string 322 in the casing string 324 and extends through the opening 334 . The member 340 is then expanded radially outward within the casing string 324 .
[0140] Expansion of the member 340 further secures the connection between the liner and casing strings 322 , 324 . Seals may be formed between the outer surface of the member 340 and the interior surface of the casing string 324 above and below the liner string 322 , and the inner surface of the liner string in the casing string. The seals are preferably formed due to contact between the member 340 outer surface and the casing and liner strings 324 , 322 inner surfaces. For example, the seals may be metal to metal seals. The seals may be formed due to a layer of sealing material on the member 340 outer surface and/or the casing and liner strings 324 , 322 inner surfaces. However, any types of seals may be used in keeping with the principles of the invention.
[0141] The member 340 may be further expanded to further outwardly deform the casing string 324 where it overlies the member, in a manner similar to that used to expand the member 186 in the method 170 as depicted in FIG. 17 . In that way, the member 340 may be recessed into the inner wall of the casing string 324 and the inner diameter D 11 of the member may be enlarged so that it is substantially equal to, or at least as great as, the inner diameter D 10 of the casing string. Due to outward deformation of the casing string 324 in the method 320 , whether or not the member 340 is recessed into the inner wall of the casing string, it may be desirable to delay cementing of the casing string in the parent wellbore 326 until after the expansion process is completed.
[0142] Thus have been described the methods 10 , 110 , 170 , 200 , 230 , 260 , 280 , 300 , 320 which provide improved connections between tubular strings in a well. It should be understood that openings and windows formed through sidewalls of tubular members and structures described herein may be formed before or after the tubular members and structures are conveyed into a well. Also, it should be understood that casing and/or liner strings may be cemented in parent or branch wellbores at any point in the methods described above.
[0143] Of course, a person skilled in the art would, upon a careful consideration of the above description of representative embodiments of the invention, readily appreciate that many modifications, additions, substitutions, deletions, and other changes may be made to these specific embodiments, and such changes are contemplated by the principles of the present invention. For example, although certain seals have been described above as being carried on one element for sealing engagement with another element, it will be readily appreciated that seals may be carried on either or neither element. Accordingly, the foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims and their equivalents. | A sealed multilateral junction system provides fluid isolation between intersecting wellbores in a subterranean well. In a described embodiment, a method of forming a wellbore junction includes the steps of sealing a tubular string in a branch wellbore to a tubular structure in a parent wellbore. The tubular string may be secured to the tubular structure utilizing a flange which is larger in size than a window formed in the tubular structure. The flange may be sealed to the tubular structure about the window by a metal to metal seal or by adhering the flange to the tubular structure. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. patent application Ser. No. 07/872,188, filed Apr. 22, 1992, now abandoned.
TECHNICAL FIELD
This invention generally relates to the transfer of bit-mapped images. More particularly, it relates to methods for recognizing and using vertical and horizontal rules to reduce the amount of data required to transfer a bit-mapped image from a first device, such as a computer, to another device that is capable of using rules, such as some printers.
BACKGROUND OF THE INVENTION
Frequently it becomes necessary to transfer digital values which comprise a bit-mapped image from a sending device, such as a computer, to a receiving device, such as a printer. Each of the digital values corresponds to an image point, hereinafter called a pel (picture element). An 8×10 inch bit-mapped image reproduced on a printer having a resolution of 300 pels per inch (ppi) can be described by 7,200,000 pels. In the simplest case wherein the pels are restricted to either black or white, an 8×10 inch bit-mapped image could be represented by 900,000 8-bit bytes. As is well known, color images require a larger number of bytes.
In the typical application wherein a bit-mapped image to be printed is stored in a computer's memory, the image must be sent to the printer. The interconnection of the computer to the printer is by either a serial or a parallel port connection. Serial connections typically can transfer data at a rate of about 1,928 bytes per second, while parallel connections are usually five to ten times faster. Ignoring any overhead required in the printer's command language, and assuming that the bit-mapped image is sent as a stream of byte values, a typical serial computer-to-printer interface might require 470 seconds to transfer a monochrome bit-mapped image. Even using a fast parallel interface, about 47 seconds might be required. Since many printers can print a page within about ten seconds after receipt of the complete bit-mapped image, the time required to transfer the data between the computer and the printer is a serious bottle neck. Therefore, methods of reducing the amount of data required to transfer a bit-mapped image are highly desirable.
Many printers provide features which can be exploited to speed up the transfer of bit-mapped images. For example, some printers can print solid lines or rectangles, hereinafter called rules, when they are provided with rule descriptors, such as the coordinates of diagonally opposing corners of the rule or the coordinates of one corner plus the height and width of the rule. A vertical rule is defined herein as a vertical line or a tall rectangle while a horizontal rule is defined as a horizontal line or a wide rectangle. Vertical and horizontal rectangle overlap in definition, and a single rectangle may alternatively be considered as a vertical or a horizontal rule.
Using rules can significantly reduce the amount of data which must be transferred from the sending device to the receiving device. For example, consider a ten inch vertical line one pixel wide. Describing that line as a vertical rule is trivial, all that must be done is to (1) specify that a vertical rule is being sent and (2) provide a suitable printer with the coordinates of the beginning and the ending points of the rule. In contrast, sending individual data bits would require at least 3,000 bytes when using a printer printing at 300 pels per inch. In practical applications, many more bytes are required since all printers require additional information, referred to as command overhead, to operate. For example, the Hewlett-Packard LaserJet II must receive 4 command overhead bytes for each new raster line. Therefore, 15,000 bytes would have to be transmitted from the computer to the printer to describe a single ten-inch line printed at 300 pels per inch. While not as dramatic, the use of horizontal rules can also significantly reduce the amount of information that must be transferred. Therefore, it would be highly useful to be able to recognize vertical and horizontal rules in a bit-mapped image and to use that information to reduce the amount of data which must be transferred from the sending device to the receiving device by using rules.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method of recognizing vertical rules in a bit-mapped image.
It is another object of the present invention to provide a method of recognizing horizontal rules in a bit-mapped image.
Yet another object of the present invention is to provide a method of reducing the amount of data required to describe a bit-mapped image.
It is another object of the present invention to provide a method of reducing the time required to print a bit-mapped image stored in a computer.
These and other objects of the present invention, which will become obvious to those skilled in the art as preferred embodiments of the invention are described more thoroughly below, are provided by methods of and systems for recognizing rules in a bit-mapped image and of using those rules to enable a suitable printer, or other such receiving device, to receive the bit-mapped image quickly. Preferred embodiments include the steps of recognizing rules in a bit-mapped image, forming rule descriptors for those rules, and then transmitting the rule descriptors to a receiving device. Preferably, vertical rules are recognized by partitioning the bit-mapped image into a plurality of adjacent horizontal stripes, each stripe comprised of a number of rows of image data. The image data of each horizontal stripe is then partitioned into vertical data columns formed from vertically aligned data bits in each of the rows comprising the horizontal stripe. Vertical lines are recognized by ANDing the data bits in each vertical data column to identify, by a HIGH output from the AND function, vertical lines which span the horizontal stripe. Rule descriptors for the vertical lines are then formed. Adjacent and continuous vertical lines are combined and identified using a single descriptor. A rule descriptor is a set of digital values useable by the receiving device to define the rule. Typically, a rule descriptor contains either the coordinates of diagonally opposite corners of the rule, or the coordinates of one corner plus the height and width of the rule. Preferably, the height of a vertical rule is determined by identifying the adjacent horizontal stripes through which the rule passes and then noting the top row of the first horizontal stripe and the last row of the last horizontal stripe through which the vertical rule passes. The width is preferably determined by identifying the first and last columns which contain the vertical rule.
Preferably, horizontal rules are recognized by partitioning individual rows of the bit-mapped image data into a plurality of 8-bit bytes. The occurrence of a horizontal line is determined by ANDing together the individual bits comprising each byte. If a HIGH output results from the AND function, a horizontal line is identified. Adjacent horizontal lines are identified by determining similar dimensioned horizontal lines in adjacent rows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a typical bit-mapped image containing vertical and horizontal rules and its characterization in accordance with preferred embodiments of the present invention.
FIG. 2 shows the preferred embodiment apparatus for practicing the inventive methods.
FIG. 3 is a tabular listing of part of a horizontal stripe which contains a vertical rule.
FIG. 4 is a tabular listing of several row and column vectors of digital data in several horizontal stripes.
FIG. 5 is an illustration of the relationship between a row vector and the various run table vectors of the preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present inventive methods reduce the amount of data needed to transfer a bit-mapped image from one device, such as a computer, to another device capable of using rules, such as some printers. In the preferred embodiments described herein, the methods involve identifying vertical and horizontal rules, solid lines or rectangles within the bit-mapped image and forming rule descriptors of the rules for transmittal to a receiving device.
The descriptions of the inventive methods are assisted by relating a bit-mapped image to an X-Y coordinate system. Each image point of the bit-mapped image, or its equivalent data value, has a particular location within the bit-mapped image which is identifiable with a specific row and column. This is illustrated in FIG. 1 wherein a bit-mapped image 2 comprised of black and white picture elements, hereinafter called pels, is shown. Each black pel will be assumed to be represented by a digital HIGH, and each white pel will be assumed to be represented by a digital LOW. FIG. 1 shows a bit-mapped image comprised of 48 rows, identified by the numbers 1R-48R starting at the top and counting down, and 64 columns numbered 1C-64C, starting at the far left and counting to the right. In practice a complete bit-mapped image may consist of thousands of individual rows and columns. Because of the correspondence between the digital values and the pels, the term "bit-mapped image" interchangeably describes the set of digital values corresponding to the pels and the set of pels corresponding to the digital values.
The pels are beneficially organized into array sets called row vectors, one row vector for each row. The row vector entries are the digital values of the pels in each row. The row vectors are numbered the same as the rows 1-48 and correspond to rows 1R-48R, respectively, from which they are formed. With reference to FIG. 1, the row vector 48 has vector entries that are sequential LOWs, except for entries 12, 13, and 14, which correspond to the pels in columns 12C, 13C, and 14C, respectively, which are HIGH. Likewise, the row vector 47 is comprised of 63 consecutive HIGH entries followed by a single LOW in entry 64. Because the row vector entries align column-wise with row vector entries in other rows, column vectors can be formed from the row vector entries. For example, a column vector 1, which corresponds to column 1C, could be formed using 46 sequential LOW entries followed by a HIGH in entry 47, followed by another LOW in entry 48. The use of column and row vectors both parallels the operation of the preferred embodiment apparatus and significantly reduces the complexity in describing and understanding the inventive methods.
The preferred apparatus for implementing the inventive methods is illustrated in FIG. 2, a simplified block diagram of a computer/printer network 72. A computer 74 includes a bit-mapped memory 76 which stores a bit-mapped image comprised of digital values. The bit-mapped image may have been created by application software, a digitizer, or may be from another device. The bit-mapped image may be applied to a video driver 78 which causes the image to be displayed on a monitor 80 for viewing by an operator. The bit-mapped image may also be applied to a printer interface 82 which creates a copy of the bit-mapped image and which processes the image data by: (1) identifying rules within the bit-mapped image; (2) creating and storing rule descriptors, and; (3) transferring those rule descriptors to a printer driver 86. Preferably, the printer interface also removes the image data corresponding to the rule descriptors from the copy of the bit-mapped image and thus only the residue data, i.e., that portion not within the rules, remains in the copy. After all rules have been identified and stored, the printer interface transfers the rule descriptors and the residue data to the printer driver 86. The operation of the computer 74 is controlled by a central processing unit 88 under the control of a software program (not shown).
All data applied to the printer driver 86 is sent via an interface bus 90 to a printer receiver 92 in a printer 94. The printer 94 must be of the type capable of using rule descriptors, such as the HP Laserjet series of printers. The printer receiver 92 receives the rule descriptors and the residue data and applies them to an image decoder 96. The image decoder 96 regenerates the original bit-mapped image by combining the bit-mapped image data described by the rule descriptors with the residue data. The regenerated bit-mapped image is then stored in a printer memory 98. When the bit-mapped image is to be printed, the printer memory 98 sends it to a print unit 100 which then prints the image.
Referring again to FIG. 1, the identification of vertical rules, such as the vertical line 142, is assisted by partitioning the bit-mapped image into a set of adjacent horizontal stripes 146; each horizontal stripe being comprised of a number of adjacent rows. For subsequent use when creating rule descriptors, the first and last row numbers of each horizontal stripe are stored in a Row Number Array. While FIG. 1 shows each horizontal stripe 146 as comprised of 8 rows of 64 pels each, frequently a bit-mapped image will have rows thousands of pels long. To recognize a vertical line traversing a horizontal stripe, column vectors are formed from the individual row vector entries of each horizontal stripe. The entries of these column vectors are ANDed together; if the AND function outputs a HIGH, a vertical line is known to traverse the horizontal stripe. An understanding of this process is assisted by reference to FIG. 3, which shows a tabular listing of the digital values of a block 148 of FIG. 1. For the column vectors 1C and 2C, the AND function produces a LOW output. However, for the column vectors 3C and 4C, the AND function produces a HIGH output, indicating that vertical lines 142 and 150 of FIG. 1 traverses block 148. The AND operations performed on the other column vectors all result in a LOW output. As shown in FIG. 3, the results of the AND function are used to form accumulation vectors, such as accumulation vector 148' shown in FIG. 4. Each accumulation vector entry corresponds to the AND result for a column vector through a horizontal stripe, i.e., the fifth entry of an accumulation vector is the AND result of the fifth column, 5C. By scanning the entries of an accumulation vector, it can readily be determined in what column vertical lines traverse the horizontal stripe. Since each horizontal stripe produces its own accumulation vector, and since each HIGH entry in an accumulation vector corresponds to a vertical line, the presence of vertical lines which pass through adjacent horizontal stripes is easily found by ANDing accumulation vector entries. This process is described in more detail below.
If short vertical lines are to be detected, the horizontal stripes could be made only a few rows wide. However, if the horizontal stripes are made too narrow, the time required to search for the vertical rules, plus the time required to create the rule descriptors and to transfer them to the printer, is more than the time required to send each pel individually. Therefore, the height of the horizontal stripes is preferably selected to maximize the benefit of recognizing and using vertical rules. While the optimum horizontal stripe height may vary from application to application and from printer to printer, a horizontal stripe of thirty four rows has been found to produce good results for general use. It can be seen that the amount of data required to describe the vertical line 142 of FIG. 1 could be minimized by using the actual starting and stopping row numbers, 18R and 41R, without reference to the horizontal stripes. In preferred embodiments, the disadvantage of not using the actual starting and stopping locations is overcome by the simplicity and efficiency of generating vertical rule descriptions dependent upon the horizontal stripes. In the preferred embodiment, portions of the bit-mapped image not contained in the rules are sent bit-by-bit to the printer.
The efficiency of recognizing and using vertical rules is further enhanced in the preferred embodiment described herein by recognizing vertical lines which span more than one horizontal stripe, such as does vertical line 142 of FIG. 1. An understanding of a preferred method of recognizing vertical lines traversing more than one horizontal stripe is assisted by FIG. 4, which provides a tabular listing of the digital values of blocks 148, 152, and 154 of FIG. 1, together with their respective accumulation vectors 148', 152', and 154'. As shown in FIG. 1, the vertical line 142 traverses both blocks 148 and 154 while the vertical line 150 traverses only block 148. Additionally, no vertical line traverses block 152. Referring now to FIG. 4, the AND function applied to block 152 results in an accumulation vector 152' having entries of all zeros. Prior to the determination of the accumulation vector 148', the accumulation vector 152' is stored as a Last -- Accumulation vector 160. When the accumulation vector 148' is determined, it is readily seen from the HIGH entries that the two vertical lines, 142 and 150, do traverse the block 148. To detect this, the accumulation vector 148' is stored as a Current -- Accumulation vector 162. Any HIGH entry in the Current -- Accumulation vector indicates that a vertical line traverses the horizontal stripe from which the Current -- Accumulation vector was developed. The Current -- Accumulation and Last -- Accumulation vectors are used to generate signals that indicate that a new vertical line has begun. With reference to FIG. 4, a New -- Vertical -- Rule vector 164 is formed from the Current -- Accumulation vector 162 and the Last -- Accumulation vector 160 as follows:
New -- Vertical -- Rule=Not (Last -- Accumulation))AND Current Accumulation
Any resulting HIGH in the New -- Vertical -- Rule vector 164 denotes the beginning of a New -- Vertical -- Rule at the column corresponding to the HIGH. The HIGH New -- Vertical -- Rule entries cause a Rule Descriptor array to store the top row number, available from the Row Number Array, of the currently processed horizontal stripe at the corresponding column addresses.
The prior Current -- Accumulation vector 162 is then stored as the Last -- Accumulation vector 166 and the next horizontal stripe is processed to form the accumulation vector 154', which is then stored as the Current -- Accumulation vector 168.
As shown by the HIGHs in FIG. 4, column 3C, the vertical line 142 (see FIG. 1) traverses block 154 while the vertical line 150 (see FIG. 1) in column 4C terminates. To detect that a vertical line has ended within the block 154, the contents of the Last -- Accumulation vector 166 is ANDed, with the inverse of the Current -- Accumulation vector 168 to produce an End -- Accumulation vector 170. Any HIGH in the End -- Accumulation vector 170 designates that a vertical line has ended in the current horizontal stripe. This causes the number of the bottom row of the horizontal stripe used to derive the Last -- Accumulation vector, available from the Row Number Array, to be stored as the ending row number in the Rule Descriptor array at the corresponding column addresses.
With the starting and ending row numbers stored in the Rule Descriptor Array at the column addresses corresponding to columns containing rule descriptors at vertical lines, rule descriptors can be constructed for transmittal to the printer. The actual form of the rule descriptors depends upon the particular printer being used and consequently reference to the specifications of the specific printer being used is required. However, for purposes of further explanation, it will be assumed that the rule descriptors consist of a starting position, comprised of a row number and column number, followed by the height of the rule, followed by the width of the rule. A width of 1 designates a vertical line.
By using accumulation vectors, it is easy to check for adjacent vertical lines by using a method best understood with reference again to FIG. 3. By ANDing pairs of adjacent entries of the accumulation vector 148' together, the adjacent HIGHs in columns 3C and 4C, are easily found. Instead of using two separate rule descriptors, one for each vertical line, the width entry of the first rule descriptor, that for the vertical line in column 3C, is preferably increased by one (1). Thus, by detecting adjacent ones in the accumulation vectors, and by incrementing the width of the first ruled descriptor found, adjacent vertical lines in a horizontal stripe can be described using a single rule descriptor.
The above procedures of recognizing vertical lines which traverse more than one adjacent horizontal stripe and for detecting adjacent vertical lines within each horizontal stripe are preferably combined to provide a rule descriptor which describes adjacent vertical lines which traverse more than one horizontal stripe. Width-wise, in the preferred embodiment this is done by searching the Last -- Accumulation vector for adjacent HIGH entries. Since the Last -- Accumulation vector has HIGH entries for vertical rules which traverse the horizontal stripe above the one currently being processed, adjacent HIGH entries denote a vertical rule which spans more than one column in that horizontal stripe. By comparing the Last -- Accumulation vector with the Current -- Accumulation vector it is determined when changes occur in the vertical rule. If a vertical rule traverses adjacent horizontal stripes, the rule descriptor for the vertical rule in the Last -- Accumulation vector has its height entry incremented. By incrementing both heights and widths, a solid black block, such as block 174 of FIG. 1, can be sent as a single rule descriptor by identifying the upper left corner, row 1R, column 33C, plus a height of 16, plus a width of 32. A non-rectangular piece of the bit-mapped image preferably is sent to the receiving device by using rule descriptors for rectangular sections. Referring again to FIG. 1, the majority of the solid black section 180 could be described using two rule descriptors:
rule descriptor 1=Row 17R, column 19C+24 (height)+5 (width)
rule descriptor 2=Row 25R, column 25C+16 (height)+9 (width)
Some portions of the section 180, residue data, are not found by the preferred embodiment vertical rule search because they are pieces which do not span a horizontal stripe. Some of these portions are found during a search for horizontal rules.
A horizontal rule, a horizontal line or rectangular, may be as small as a single horizontal line of pels or may completely cover the image. A single horizontal line of pels spanning a ten-inch wide landscape image printed on a printer capable of printing 300 dots per inch would require at least 375 bytes to transfer byte-by-byte. However, as discussed with reference to the vertical rules, printers require additional data as part of their printer command overhead. As with vertical rules, the amount of data required to transfer a horizontal rule can be substantially reduced by exploiting the rule descriptor capabilities of some printers.
An understanding of a preferred method of recognizing a horizontal line is assisted by FIG. 1, specifically the horizontal line in row 47R. That horizontal line is preferably recognized by dividing row vector 47, into adjacent sequences of 8-bit bytes, and then ANDing the digital values of each byte together. If the AND function produces a HIGH, a horizontal line at least one byte long is found. While the partitioning of the row vector into groups shorter than a byte would result in shorter lines being found, the advantages of using rule descriptors could be lost since it might be quicker to send short lines byte-by-byte than to search for and use rule descriptors. A rule descriptor could be formed using the row number and the starting and ending column numbers for each byte that produces a HIGH from the AND function. Provided that the amount of data required to signal the printer that a rule descriptor follows and to send the rule descriptor to the printer is less than the amount of data required to transmit the horizontal line byte-by-byte, a reduction in the amount of data required to be transferred is achieved.
However, in the preferred embodiment described herein, the use of horizontal rules is further enhanced by recognizing adjacent horizontal lines in the same row and adjacent rows which contain similar horizontal lines. Assuming again that rule descriptors are comprised of the row and column numbers of the upper left hand pel, plus the width, plus the height of the rule, adjacent rows containing similar horizontal lines can be described using only one descriptor. For example, referring again to FIG. 1, part of the residue of block 180 can be described as a rule beginning in row 41R, column 17C, 16 columns wide and three rows high, thereby defining the horizontal rectangle having diagonal comers 190 and 192.
Determining a horizontal line which spans more than one byte is readily accomplished. By applying the entries of the row vector to the ANDing function a byte at a time, the first HIGH from the AND function designates the start of a horizontal line and the far left column number, along with the row vector number, is stored in the Rule Descriptor array. The next byte of the row vector which does not produce a HIGH from the AND function causes the far right column number of the previous byte to be stored as the ending column of the horizontal line. Subsequent bytes which produce a HIGH from the AND function of the row vector will also cause entries in the Rule Descriptor array.
While finding byte-long horizontal lines in a row is a simple process, the recognition of horizontal rules which span several adjacent rows is more involved. According to the preferred embodiment described herein, the identification of such horizontal rules involves 6 arrays: the Rule Descriptor array previously described; 3 run table vectors; and 2 rule descriptor address vectors. The first run table vector, called the RunTable N! vector, contains a description of all horizontal lines in the row vector being searched that traverse a byte. Specifically, the descriptions in the RunTable N! vector include the number of sequential bytes which produces HIGHs from the AND function information, which is stored at the address corresponding to the first column of the first byte which produces a HIGH, and, at the next address location, the negative inverse of the number of bytes between bytes which output HIGHs. This is better understood with reference to FIG. 5, wherein a row vector 200 is shown with a RunTable N! vector 202 and two other run table vectors which are described below. Row vector 200 produces HIGHs in bytes corresponding to locations 1-9, 11-13, and 17-24. To designate the number of sequential bytes which produce HIGHs, the RunTable N! vector 202 has entries of 8 in address 1, 3 in address11, and 8 in address 17. To designate the space between sequential HIGH runs, the Run Table N! vector 202 has a -1 at address 2, a -3 at address 12, and a -8 at address 18. It is assumed that the row vector 200 of FIG. 5 is being compared with an adjacent row vector 199 (not shown). Another run table vector, called the RunTableLast vector 204, contains a similar description of the row vector 99 as that in the RunTable N! vector 202. Finally, another run table vector, called the RunTableVertical vector 206 contains a similar description of the accumulation vector of the horizontal stripe containing the row vector 200.
By comparing the entries of the RunTable N! vector with the corresponding entries of the RunTableLast and RunTableVertical vectors it is readily determinable whether a new horizontal rule is in the row vector 200. For example, with reference to FIG. 5, the address 1 entries of the RunTable N! vector 202 and the RunTableVertical vector 206 are the same. Therefore, it is known that the horizontal line in the row vector 200 is a part of a vertical rule. Because, in the preferred embodiment, rule descriptors are formed for vertical rules before horizontal rules, and because it is known that a vertical rule descriptor already exists which describes the horizontal line, no further action need be taken.
If, however, the RunTableVertical vector 206 does not have an entry at an address, but the RunTable N! vector does, the RunTable N! vector is compared with the RunTableLast vector 204. For example, referring to FIG. 5, in column 17C the RunTable N! vector 202 and the RunTableLast vector 204 have identical entries. This indicates two adjacent similar horizontal rules in row vectors 199 and 200. Since the horizontal rules share the same starting column and extend for the same length, only one rule descriptor is needed. This rule descriptor is obtained by incrementing the rule descriptor for the rule in the higher row, that corresponding to the RunTableLast vector 204, by one(1) .
If, however, the RunTableVertical vector 206 and the RunTableLast vector 202 do not contain entries where the RunTable N! vector 204 does contain an entry, it is known that a new horizontal rule in the form of a line exists in the row vector 200. For example, address 11 of RunTable N! vector 202 contains an entry 3 which indicates that the row vector 200 has a horizontal line which is at least 24 columns long.
The process of incrementing the height of an existing rule descriptor upon the occurrence of a similar horizontal line in an adjacent row may be extended to describe many adjacent similar horizontal lines. To assist in finding the number of similar horizontal lines in adjacent rows, the preferred embodiment described herein uses two additional vectors: P -- Rule -- Last and P -- Rule -- Current. The entries of P -- Rule -- Last are the addresses of the horizontal rule descriptors found prior to the search of the current row. When a horizontal line in the current row is found, the contents of the P -- Rule -- Last vector at the address of the first column of the horizontal line is checked. If the P -- Rule -- Last vector contains an address at that location, and if the rule at that address is similar to the horizontal line found, the contents of the height entry of the rule at the stored address is incremented by 1 and a copy of that address is stored into P -- Rule -- Current. However, if the horizontal rule is not a continuation from the previous row, i.e., it not similar to the horizontal line previously found or is new, a rule descriptor for the new horizontal line is created and the address of that rule is stored within P -- Rule -- Current. Upon the completion of the search of the current row, P -- Rule -- Current contains the addresses of all of the horizontal rules within the currently scanned row. Prior to the search of the next row, the RunTable N! vector is copied into the RunTableLast vector and the P -- Rule -- Current is copied into the P -- Rule -- Last vector. After theses swaps, the entries of the vectors RunTable N! and P -- Rule -- Current are all set to zero, and horizontal rules are searched for in the next row.
After all of the vertical and horizontal rules have been found and their rule descriptors are created, the rule descriptors in the rule descriptor array are sent to the receiving device. The particular form of transmittal may vary. In the preferred embodiment described herein a text string of the rule descriptors is composed. After receipt of the text string, the receiving device preferable recomposes into its memory the portions of the bit-mapped image described by the rule descriptors.
It should be noted that some parts of the bit-mapped image are not described by the rule descriptors. Depending upon the applications, this residue is either ignored or sent by other techniques, such as bit-by-bit. To assist in the process, the portions of the bit-mapped image described by the rule descriptors are preferably removed from the bit-mapped image. This entails zeroing all HIGH pel values described by the rule descriptors. The residue can then be sent to the receiving device, bit-by-bit, and then be added to the portions sent via the rule descriptors to recreate the original bit-mapped image.
It is to be understood that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing, together with details of the structure and function of the invention, the above disclosure is illustrative only. Changes may be made in details and yet remain within the principles of the invention, which are defined by the appended claims. | Methods of recognizing rules, solid lines or rectangles, in a bit-mapped image and of using those rules to enable a suitable printer or other suitable device to receive the bit-mapped image quickly. In a preferred embodiment, the methods include the steps of recognizing rules, forming rule descriptors for the rules, and then transmitting the rule descriptors to the receiving device. Vertical rules are recognized by partitioning the bit-mapped image into a plurality of adjacent horizontal stripes of row data, dividing that horizontal stripe into data columns formed from vertically aligned row data bits, and ANDing the data bits in each vertically aligned column to identify, by a HIGH output from the AND function, vertical lines which span the horizontal stripe. Adjacent or continuous vertical lines are then identified. Horizontal rules are identified by dividing the row data into bytes, ANDing individual bits of each byte together, and recognizing a horizontal line by a HIGH output from the AND function. Adjacent horizontal lines are identified and combined. Horizontal rule descriptors are then formed and sent to the printer or other receiving device. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an intake system for an internal combustion engine having a supercharger.
2. Description of Related Art
In recent years, a number of different considerable types of internal combustion engines have been provided with various types of superchargers to supercharge intake air.
In these types of superchargers, their supercharging pressures to be imposed on the intake air are generally limited in their ability to ehnace the intake air pressure by some limiting factors determined by engine characteristics. Taking the upper limits of the supercharging pressure into consideration in relation to engine speeds, in a low engine speed range, the supercharging pressures are to be limited in order to prevent knocking of the engine. In a middle engine speed range, the supercharging pressures are to be limited to assure the presence of appropriate combustion pressures. In a high engine speed range, the supercharging pressures are to be limited for to ensure the presece of appropriate heat loads thereof. In permissible supercharging pressures thus defined by these limiting factors, the permissible supercharging pressures depending on heat load of the engine are, in general, in the lowest level. Therefore, in conventional engines, the maximum supercharging pressures have been substantially selected on the basis of the permissible supercharging pressure depending on the heat loads of the engines.
In internal combustion engines with superchargers as set forth above, it has been proposed that intake systems of the engines be arranged to supercharge the intake air further with a so-called kinetic supercharging effect of intake air (See, for example, Japanese Utility-Model Laid-Open Publication No.62-49625). The kinetic effect is intended to improve the volumetric efficiency of cylinders of the engine so as to enhance the torque of the engine. Such a kinetic effect includes both an inertia effect of intake air and a resonance effect of intake air .
Since a preferred nature of the kinetic effect is obtained in synchronism with a certain engine speed, to obtain take the kinetic effect in an intake system, it has been proposed to provide a means for allowing the intake system to correspond to different engine speeds, thereby providing the advantageous kinetic effect in a wide range of the engine speeds.
For example, U.S. Pat. No. 4,829,941, issued on May 16, 1989 to the same assignee as the present application, discloses one type of intake system having means for changing over the length of the resonance air column in the intake system on the basis of the engine speeds to obtain an advantageous intake air resonance effect over a wide range of engine speeds. Further, the U.S. Pat. No. 4,617,897, issued on Oct. 21, 1986 to the same assignee as the present application, discloses another type of intake system which is adapted to change the length and the cross-sectional area of the intake passage to obtain a preferred intake air inertia effect over a wide range of engine speeds. Furthermore, U.S. Pat. No. 4,651,684 issued on May 24, 1987 to the same assignee as the present application, discloses still another type of intake system in which the valve timing of the intake valve is changed, so as to vary the opening time thereof according to the operating condition of the engine, so that the volumetric efficiency is improved.
In the conventional engines with superchargers such as those previously mentioned, since the maximum value of the supercharging pressure provided by the supercharger is determined on the basis of a limiting factor which depends on the heat load of the engine, the engine can afford to enhance the supercharging pressures in low and middle engine speed ranges. Therefore, it is taken into consideration that the maximum supercharging pressure is shifted in accordance with a parameter defined by engine speeds. In other words, when, in simplification, the engine speed range is supposed to be divided into a relatively low range and a relatively high range, the maximum supercharging pressure is set to a high value in the low engine speed range and the maximum supercharging pressure is set to a low value in the high engine speed range, thereby changing the maximum supercharging pressure over between low and high values in accordance with the engine speeds.
However, in such an arrangement, at the time the maximum supercharging pressure is shifted, there is generated a great fluctuation in engine torque, that is, a torque shock, and, therefore, consideration of this problem has been required.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an internal combustion engine with a supercharger which avoids the generation of torque shock at the time when the maximum supercharging pressure of the supercharger is shifted.
In accordance with the present invention, there is provided:
an intake system for an internal combustion engine with a supercharger including:
passage means for introducing intake air into each of the cylinders of the engine, having first intake passages each of which is individually connected with each of the cylinders and a second intake passage which is in communication with the first intake passages;
supercharging means having a compressor which is disposed in the second intake passage for supercharging the intake air;
control means for varying supercharging pressure provided by the supercharger according to operating conditions of the engine;
varying means for changing characteristics of the kinetic effect of the intake air so that a desired kinetic effect can be obtained in accordance with the operating conditions; and
synchronizing means for synchronizing a timing or timings for varying the characteristics of the kinetic effect by the varying means with a timing or timings for varying supercharging pressure by the control means.
In accordance with the present invention, a reduction in torque generated at the time when the supercharging pressure is shifted, can be compensated for by enhancement of the torque generated at the time when characteristics of kinetic effect of intake air vary. Thus, in an internal combustion engine with supercharger, an improved intake system which accommodates advantageously to both the functions of the supercharger and the kinetic effect of intake air can be obtained. In other words, the torque curve of the engine can be improved as a whole so that it is a smooth torque curve and great fluctuation of the torque, namely, torque shock upon the shift of the supercharging pressure is not generated.
DESCRIPTION OF THE DRAWINGS
These and other objects and features of the invention will be more understood with reference to the following detailed description of illustrative embodiments of the invention, taken in connection with the accompanying drawings, in which:
FIG. 1 is a schematic plan view illustrating diagramatically an internal combustion engine provided with an intake system in accordance with an embodiment of the present invention.
FIG. 2 is a graphical representation showing the characteristics in operation of the engine shown in FIG. 1.
FIG. 3 is a graphical representation showing relationships among the limiting factors, maximum supercharging pressures and engine speeds for shifting the maximum supercharging pressure.
FIG. 4 is a schematic plan view illustrating diagrammatically an internal combustion engine provided with an intake system in accordance with another embodiment of the present invention.
FIG. 5 is a schematic plan view illustrating diagramatically an internal combustion engine provided with an intake system in accordance with still another embodiment of the present invention.
FIG. 6 is a graphical representation showing a change in the valve timing of the engine shown in FIG. 5 in relation to the crank angles.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, an Otto-cycle four-cylinder engine 1 is shown therein, each of the cylinders C1-C4 of the engine 1 being provided with an intake port 2 and exhaust port 3. The intake ports 2 and the exhaust ports 3 are opened or closed in timed relations in synchronism with rotation of a crankshaft (not shown) of the engine by intake valves and exhaust valves (not shown), as is well-known in the art.
An intake passage 11 for introducing intake air into the cylinders C1-C4 has in its way a surge tank 12, which functions as a first pressure reflecting portion. The surge tank 12 is adapted to be supplied with the intake air through one common intake passage 13, which is provided with an air cleaner 14, an air-flow meter 15, a compressor 16a of a turbo-type supercharger (referred to hereinafter as a "turbo-charger"), and an inter cooler 17, one after another from an upstream side.
The intake passage 11 is divided into two branch intake passages 18A and 18B on its downstream side of the surge tank 12, and the branch intake passages 18A, 18B are provided with throttle valves 19A, 19B, respectively, which operate in an interlocked relation with each other. On a downstream side of the throttle valve 19A, the branch intake passage 18A individually communicates through discrete intake passages 20-1, 20-4 with each of the intake ports 2 of the first and fourth cylinders C1, C4, which do not fire successively. Further, on a downstream side of the throttle valve 19B, the branch intake passage 18B individually communicates through discrete intake passages 20-2, 20-3 with each of the intake ports 2 of the second and third cylinders C2, C3, which do not fire successively. Each of the discrete intake passages 201 1˜20˜4 is provided with a fuel injection valve 21.
The branch intake passages 18A and 18B can be, on their end portions opposite to the surge tank 12, in communication with each other through a communicating passage 22 which functions as a second pressure reflecting portion. The communicating passage 22 is provided with an on-off valve 23 which can open and close the communicating passage 22. The distance between each of the intake ports 2 and the surge tank 12 (the first pressure reflecting portion) taken along the discrete passage and the branch passage, is set to be larger than the distance between each of the intake ports 2 and the communicating passage 22 (the second pressure reflecting portion) taken along the discrete and branch passages. Therefore, when the on-off valve 23 is closed, the surge tank 12 comes to act as the pressure reflecting portion and the resonance air column is set to a relatively long length, so that the length of the resonance air column can correspond to a relatively low engine speed range for obtaining the proper kinetic effect of intake air therein. On the other hand, when the on-off valve 23 is opened, the communicating portion comes to act as the pressure reflecting portion and the resonance air column is set to a relatively short length, so that the length of the resonance air column can correspond to relatively high engine speed range for obtaining the proper kinetic effect of intake air therein. Variations in the volumetic efficiency involved in such opening and closing of the on-off valve 23 are shown in FIG. 2(a), in which the curve X1 represents the variation in a state where the on-off valve 23 is closed and the curve Yl indicates the variation in a state where the on-off valve 23 is opened.
Further, an exhaust passage 24 in communication with the exhaust ports 3 is joined into a single passage, and on the downstream side of the joined portion, a turbine 16b of the turbo-charger 16 is located. The turbine 16b is connected to the compressor 16a by means of a shaft 16c, so that the rotation of the turbine 16b by the energy of the exhaust gas allows the compressor 16a to rotate to effect asupercharging of the intake air. Still further, the exhaust passage 24 is provided with a by-pass passage 25 for bypassing the turbine 16b, in which a waste gate valve 26 is disposed for defining the maximum pressure of the supercharged intake air.
The pressure for opening the waste gate valve 26 is adjusted by an actuator 31 reciprocating in responses to fluid-pressure. The actuator 31 has a first diaphragm 31b which defines a first chamber 31a and a second diaphragm 31d which defines a second rhamber 31c, and the first and second diaphragms 31b, 31d are connected to the waste gate valve 26 by means of a shaft 32. The waste gate valve 26 is normally energized by a return spring 31e so as to close the by-pass passage 25.
The first chamber 31a normally communicates by way of a signal line 33 with the common intake passage 13 on the downstream side of the ccmpressor 16a. The second chamber 31c is connected to the signal line 33 by way of a signal line 35 and a solenoid operated three way control valve 34 connected with the signal line 35. The control valve 34 has a first position in which the signal line 35 communicates with the signal line 33, and a second position in which the signal line 5 is released to the atmosphere. Therefore, when the control valve 34 takes the second position, the second chamber 31c is released to the atmosphere and the supercharging pressure provided by the turbo-charger 16 acts on only the first chamber 31a, so that the waste gate valve 26 is to be opened when the supercharging pressure reaches the first maximum supercharging pressure PMl which is determined to be a relatively high value. On the other hand, when the control valve 34 takes its first position, the supercharging pressure provided by the turbo-charger 16 acts on both the first and second chambers 31a, 31c (so that the waste gate valve 26 is to be opened when the supercharging pressure. reaches the second maximum pressure PM2 which is determined to be a relatively low value. These different maximum pressures PM1 and PM2 are indicated in FIG. 2(c).
Further, the on-off valve 23 is opened and closed by an actuator 36 reciprocating in response to fluid-pressure. The actuator 36 has a diaphragm 36b which defines a chamber 36a, and the diaphragm 36b is connected to the on-off valve 23. The chamber 36a is in communication with a signal line 37 which branches from the signal line 35 downstream of the control valve 34. Therefore, when the control valve takes the second position, the chamber 36a is released to the atmosphere so that the on-off valve 23 is closed. On the other hand, when the control valve 34 resides in the first position, the super-charging pressure acts on the chamber 36a so that the on-off valve 23 is opened. Thus, the on-off valve 23 is operated corresponding to a shift of the maximum supercharging pressure to vary the length of the resonance air column for obtaining desired of intake air kinetic effect, and the engine speed at which the maximum pressure is shifted, and at which the on-off valve is operated, is indicated by a line E2 in FIG. 2.
In order to change over the positions of the control valve 34 on the basis of the engine speeds, there is provided a control unit U, and an engine speed signal is introduced into the control unit U from an engine speed sensor 38. The control unit U operates the control valve 34 in such a manner as above described when the engine speed reaches the value E2.
In FIG. 2b, torque curves of the engine are shown, which are provided by the aforementioned position control of the control valve 34. The curve X2 of the torque curves represents the engine torque in the case where the maximum supercharging pressure is set to PM1 and the resonance air column is set to a relatively long length, and the curve Y2 of the torque curves represents the engine torque in the case where the maximum supercharging pressure is set to PM2 and the resonance air column is set to a relatively short length. The engine speed E2 is to be selected so as to correspond to the intersection of the curve X2 and the curve Y2, and the value of E2, in conventional type of engines is generally seleced to, be for example, 2500 rpm˜3000 rpm. Further, the torque curve Z represented in FIG. 2(b) by a phantom line indicates the engine torque in a case where the maximum supercharging pressure would be constantly set to be PM2 and the resonance air column would be set to a relatively long length an overall engine speed range. Still further, the engine speed E1 shown in FIG. 2(d) indicates an engine speed selected in a conventional manner such that the length of the resonance air column is changed over at the engine speed for obtaining the appropriate kinetic effect of intake air with the maximum supercharging pressure kept at a constant value.
In FIG. 3, there is shown how the aforementioned engine speed E2 and maximum supercharging pressure PM1, PM2 is selected in relation to limiting factors of the supercharging pressure for ensuring an appropriate operation of the engine. In FIG. 3, a line α indicates a limiting line for preventing knocking of the engine, a line β0 indicates a limiting line for maintaining appropriate combustion pressure, and a line γ indicates a limiting line for ensuring appropriate heat load.
It will be understood from the description as set forth above that, according to the present invention, when the maximum supercharging pressure is shifted in accordance with the engine speed ranges of the engine, the torque shock at the time of shifting the pressure can be prevented. Further, since the supercharging pressure can be enhanced in a relatively low engine speed range, the advantageous torque in an Otto-cycle engine can be ensured during operation of the engine in the low engine speed range. Further in a diesel engine, the response thereof can be advantageously ensured particularly during quick accelerating.
FIG. 4 shows another embodiment according to the present invention, in which the members or mechanisms equal to the ones shown in FIG. 1 are designated by the same reference numerals as used in FIG. 1.
In the present embodiment, there is provided a socalled mechanical-type supercharger which is mechanically driven by a crankshaft the engine. That is, a Roots-type supercharger 41 is disposed in a common intake passage 13, and the supercharger 41 is connected to the crankshaft of engine 1 by means of an electromagnetic clutch 42. A throttle valve 43 is disposed on the upstream side of the supercharger 41 in the common intake passage 13. On the downstream side of the throttle valve 43, the common intake passage 13 has a by pass passage 44 and a relief passage 45 arranged in parallel so as to be able to bypass the supercharger 41. The by pass passage 44 is provided with an on-off valve 46, and the relief passage 45 is provided with an on-off valve 47. The on-off valve 46 and 47 and an on-off valve 23 disposed in a communicating passage portion 22 are adapted to be opened or closed by electromagnetic actuators 49, 50 and 48, respectively. Further, there is provided a control unit U, into which a signal from a supercharging pressure sensor 51 for sensing supercharging pressure and a signal from an engine speed sensor 38 are inputted.
In the engine 1 having the arrangement as above described, when the engine speeds is lower than a predetermined speed, that is, when the engine speed reside in a range in which driving resistance of the supercharger is not greatly increased, the clutch 42 is operatively connected to drive the supercharger 41. Simultaneously, the on-off valve 23 as well as the on-off valve 46 are kept in their closed position so that a surge tank 12 defines a pressure reflecting portion to form a relatively long resonance air column.
On the other hand, when the engine speed is increased to a lever higher than the predetermined speed, the clutch 42 is released to disengage from the supercharger 41 so that supercharger 41 is not driven, and the on-off valve 23 is opened. This allows the maximum supercharging pressure to shift to a level (actually, supercharging effect by the supercharger 41 is not provided) and the resonance air column to change to a short length. Further, as easily understood, while the supercharger 41 is not operated, the on-off valve 46 is forced to be opened.
As set forth above, since the length of the resonance air column, in order to obtain an advantageous kinetic effect of intake air, is changed over in synchronism with the switching of the supercharger 41 between an operating state and a nonoperating state, the torque shock generated in the engine 1 upon the switching therebetween can be prevented, similar to the aforementioned embodiment shown in FIG. 1.
In addition, the on-off valve 47 located in the relief passage 45 is opened in a case in which the supercharging pressure is extraordinarily increased for any reason during operation of the supercharger 41. Alternatively, the on-off valve 47 may be used to shift the supercharging pressure during operation of the supercharger 41 as in the aforementioned embodiment shown in FIG. 1, wherein the on-off valve 23 is operated to open or close synchronously with the shift of the supercharging pressure by the on-off valve 47.
FIG. 5 shows still another embodiment in accordance with the present invention, in which the members or mechanisms corresponding to the ones shown in FIG. 1 are designated by the same reference numerals as used therein.
In an internal combustion engine 1 according to the present embodiment, there is provided a valve timing control mechanism 60, which comprises a cam shaft assembly 61 for driving intake valves (not shown) to open and close intake ports 2, a sleeve 60a, generally H shaped in section and incorporated into the cam shaft assembly 61, and a shift lever 60b adapted to be controlled by a contr..ol unit U. The cam shaft assembly 61 is divided into two portions 61a and 61b, with one being a cam shaft associated with cams for driving intake valves, the other being a portion connected with a pulley 62 which is driven in rotation by a crankshaft (not shown) by means of a timing belt (not shown). The portions 61a, 61b are respectively formed at their opposite end portion with helical splines 63a, 63b, which are oriented in opposite directions, and internal peripheral portions of two flanges 60a 1 and 60a 2 of the sleeve 60a respectively engage with the helical splines 63a,63b. The control unit U inputs control signals into the shift lever 60b.
When the engine 1 has such an arrangement, a relative phase angle between the portions 61a and 61b of the cam shaft assembly 61, that is, a relative phase angle between the cam shaft and the crankshaft (not shown), is controlled by the sleeve 60 so that the intake valves are opened and closed in accordance with valve timing shown by a solid line in FIG. 6 when the engine speed is in a low speed range less than a predetermined engine speed. Thus, the intake valves are closed at a relatively early timing in the low engine speed range. Therefore, the charging efficiency is enhanced in the low engine speed range and thus, the torque of the engine varies substantially along a predetermined torgue curve such a the torque curve X2 shown in FIG. 2(b).
As the control unit U senses, on the basis of the signals inputted from an engine speed sensor 38, that the engine speed has increased up to the predetermined engine speed, the control unit U outputs a control signal to the shift lever 60b and permits the shift lever 60b to move the sleeve 60 axially. Since the helical splines 63a and 63b are oriented in opposite directions, flanges 60a 1 and 60a 2 of the sleeve 60 allow the portions 61a and 61b of the cam shaft assembly 61 engaging therewith to rotate in opposite directions relative to each other, so that the relative phase angle between the portions 61a and 61b, namely between the cam shaft and the crankshaft is changed. Thereby, the timing for closing the intake valve is retarded as shown by a dotted line of FIG. 6. Therefore, the charging efficiency is enhanced in the high engine speed range, and the engine torque varies substantially along a desired torque curve such like the torque curve Y2 shown in FIG. 2(b).
At the time when the valve timing is displaced so as to retard the timing for closing the intake valve, the control unit U permits a three way control valve 34 to operate an actuator 31 to shift the maximum permissible supercharging pressure a relatively low pressure.
As can be understood from the aforementioned matters, in the present embodiment, since the valve timing control mechanism 60 displaces the valve timing for closing the intake valve to change the condition of intake air and at the same time, the control valve 34 allows the waste gate valve 26 to shift the maximum supercharging pressure, high charging efficiency of intake air can be ensured over a wide range of engine speeds, and knocking of the engine can be prevented.
Further, although in this embodiment, the relative phase angle between the cam shaft and the crankshaft is changed, and thereby the valve timing is displaced to change the valve timing for closing the intake valve, the lifting stroke may be changed to increase or decrease a period of opening time of the intake valve so as to change only the valve closing timing.
Still further, in the embodiments as set forth above, the maximum supercharging pressure is set to two different pressures, and the maximum pressure is stepwisely changed to either of them. However the maximum pressure may be set to three or more than three different pressures, which can respectively, apply properly to the limiting lines shown in Fugure 3, and further, the length of resonance air column for obtaining the resonance effect may be changed over to three or more than three lengths.
Also, the manner for controlling the maximum supercharging pressure has been described as a manner wherein the waste gate valve adjusts the exhaust air flow introduced into the turbine of turbine-type supercharger, and another manner wherein the connecting condition between the crank shaft of the engine and the compressor of the mechanical-type supercharger is changed (engaged or disengaged). However, other various manners for control of the supercharging pressure known in the art, for example, a manner wherein the relief passage relieves the supercharging pressure provided by the compressor of the mechanical-type supercharger, can be adaptd in accordance with the present invention.
While the embodiments of the present invention, as herein disclosed, constitute preferred forms, it is to be understood that other forms might be adopted. | In an internal combustion engine with a supercharger, a timing or timings for varying characteristics of kinetic supercharging effects of intake air are synchronized with a timing or timings for varying supercharging pressures by the supercharger. Reduction in engine torque at the time when the supercharging pressure is shifted, can be compensated for by enhancement in the engine torque generated at the time when the characteristics of the kinetic effect are varied. | 5 |
FIELD OF THE INVENTION
[0001] The present disclosure relates to the technical field of wireless communication technologies, and more particularly to a mobile terminal and a wireless connection method thereof.
BACKGROUND OF THE INVENTION
[0002] WIFI (Wireless Fidelity) is applied in more and more mobile terminals. As a standard component of the mobile terminals, WIFI chips can establish WIFI connection with access points (APs) for data communication. Nowadays, people are using WIFI connections more and more frequently in the daily life, study and work, so access points have been deployed in many houses and also been deployed in many public places such as cafes, airports, stations, libraries and so on. Thus, the mobile terminals can be connected to the internet via the access points.
[0003] In many circumstances, there is more than one access point. When there are a lot of access points, a conventional way to search for and access an access point is as follows: search for all available access points in the current environment, then look for an access point pre-recorded by the user from all the access points one by one, and use access information pre-stored by the user to access the access point once the pre-recorded access-point is found, thus complete the connection process. This requires it must complete the searching process and then access, thus the speed of accessing the access point is slow particularly when the number of the access points is great, and it adversely affects the users' experiences.
SUMMARY OF THE INVENTION
[0004] A primary object of the present disclosure is to provide a mobile terminal and a wireless connection method thereof, which can connect to an access point after each time the access point is found.
[0005] To solve the aforesaid technical problem, a technical solution adopted in the present disclosure is to provide a wireless connection method for a mobile terminal, which comprises: beginning to search for an access point in a current environment; determining whether any access point is found within a predetermined time, and if a determination result thereof is yes, acquiring a current access point that is found and suspending the searching; determining whether access information that is pre-recorded matches the current access point, and if a determination result thereof is yes, determining whether another access point has been accessed; determining whether the current access point has a priority level higher than that of the another access point if the another access point has been accessed, wherein the priority level is represented by a signal strength; disconnecting the connection with the another access point and using the access information to access the current access point if the priority level of the current access point is higher than that of the another access point; saving the current access point into a list; and continuing to search for a next access point, and returning to the step of determining whether any access point is found within a predetermined time.
[0006] The wireless connection method further comprises: ending the searching if the determination result of the step of determining whether any access point is found within a predetermined time is no.
[0007] The wireless connection method further comprises: executing the step of saving the current access point into a list if the determination result of the step of determining whether access information that is pre-recorded matches the current access point is no.
[0008] The wireless connection method further comprises: executing the step of using the access information to access the current access point if the determination result of the step of determining whether another access point has been accessed is no.
[0009] The wireless connection method further comprises: executing the step of saving the current access point into a list if the determination result of the step of determining whether the current access point has a priority level higher than that of the another access point is no.
[0010] The wireless connection method further comprises: arranging all access points in the list in a descending order according to priority levels thereof after the searching is ended.
[0011] To solve the aforesaid technical problem, another technical solution adopted in the present disclosure is to provide a wireless connection method for a mobile terminal, which comprises: beginning to search for an access point in a current environment; determining whether any access point is found within a predetermined time, and if a determination result thereof is yes, acquiring a current access point that is found and suspending the searching; determining whether access information that is pre-recorded matches the current access point, and if a determination result thereof is yes, using the access information to access the current access point; saving the current access point into a list; and continuing to search for a next access point, and returning to the step of determining whether any access point is found within a predetermined time.
[0012] The wireless connection method further comprises: ending the searching if the determination result of the step of determining whether any access point is found within a predetermined time is no.
[0013] The wireless connection method further comprises: executing the step of saving the current access point into a list if the determination result of the step of determining whether access information that is pre-recorded matches the current access point is no.
[0014] After the step of determining whether access information that is pre-recorded matches the current access point and before the step of using the access information to access the current access point, the wireless connection method further comprises: determining whether another access point has been accessed if the determination result of the step of determining whether access information that is pre-recorded matches the current access point is yes, and if a determination result thereof is no, executing the step of using the access information to access the current access point.
[0015] After the step of determining whether another access point has been accessed, the wireless connection method further comprises: determining whether the current access point has a priority level higher than that of the another access point if the determination result of the step of determining whether another access point has been accessed is yes; and if a determination result thereof is yes, disconnecting connection with the another access point and executing the step of using the access information to access the current access point.
[0016] The step of determining whether the current access point has a priority level higher than that of the another access point further comprises: saving the current access point into the list if the determination result thereof is no.
[0017] The priority level is represented by a signal strength.
[0018] The wireless connection method further comprises: arranging all access points in the list in a descending order according to priority levels thereof after the searching is ended.
[0019] To solve the aforesaid technical problem, a further technical solution adopted in the present disclosure is to provide a mobile terminal, which comprises: a WIFI chip, being configured to search for and access an access point; and a baseband-signal processing chip, being connected with the WIFI chip and comprising a control module, a first determining module, a second determining module and a storage module therein, with a list being provided in the storage module, wherein: the control module is configured to control the WIFI chip to begin to search for an access point in a current environment according to an operation of a user; the first determining module is configured to determine whether any access point is found by the WIFI chip within a predetermined time, and if a determination result thereof is yes, notify the storage module to acquire a current access point that is found and notify the control module to control the WIFI chip to suspend the searching; the second determining module is configured to determine whether access information that is pre-recorded in the storage module matches the current access point if the determination result of the first determining module is yes, and if a determining result of the second determining module is yes, notify the control module to control the WIFI chip to access the current access point by using the access information and control the WIFI chip to continue to search for a next access point, and notify the storage module to save the current access point into the list.
[0020] The baseband-signal processing chip further comprises a power-supply management module for supplying power to the WIFI chip.
[0021] The present disclosure has the following benefits: as compared with the prior art, the mobile terminal and the wireless connection method thereof of the present disclosure suspend the searching after an access point is found, determine whether access information that is pre-recorded matches the access point, and access the access point if the determination result is yes and then continue to search for a next access point. In this way, by connecting to an access point after each time the access point is found, the mobile terminal can access the access point quickly to improve the users' experiences.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a schematic flowchart diagram of a wireless connection method for a mobile terminal according to a first embodiment of the present disclosure;
[0023] FIG. 2 is a schematic flowchart diagram of a wireless connection method for a mobile terminal according to a second embodiment of the present disclosure; and
[0024] FIG. 3 is a schematic structural view of a mobile terminal according to an embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE INVENTION
[0025] The present disclosure will be detailed herein below with reference to the attached drawings and the embodiments.
[0026] Refer to FIG. 1 , which shows a schematic flowchart diagram of a wireless connection method for a mobile terminal according to a first embodiment of the present disclosure. The wireless connection method comprises following steps of:
[0027] Step S 11 : beginning to search for an access point in a current environment.
[0028] When there are access points available for use in the current environment, it begins to search for the access points in the current environment according to the user's choice.
[0029] Step S 12 : determining whether any access point is found within a predetermined time, and if a determination result thereof is yes, acquiring a current access point that is found and suspending the searching.
[0030] The user does not know whether any access point exists in the current environment when searching for the access points, and if the searching is continued when there is no access point in the current environment, the power consumption will be undoubtedly increased and also, the user may become puzzled. Therefore, a predetermined time is set. If no access point is found within the predetermined time (i.e., if the determination result is no), the searching is ended; and if an access point is found, the searching is suspended to execute a next step. In this way, the user can promptly find out if there is any available access point nearby, and may choose to connect to the internet in other ways when there is no available access point.
[0031] Step S 13 : determining whether access information that is pre-recorded matches the current access point, and if a determination result thereof is yes, using the access information to access the current access point.
[0032] The access information is verification information for accessing an access point, and comprises the access point name, the access point type, the access password, the encryption mechanism and so on. There may be a plurality of kinds of access information, with each kind matching one access point. The access information is pre-recorded, and specifically, the access information may be acquired when the user accesses an access point before, may be inputted manually by the user before the user begins to search for an access point, or may be acquired from the outside through the near field communication connection (e.g., NFC (Near Field Communication)), and the present disclosure has no limitation on the way to acquire the access information.
[0033] If the access information that is pre-recorded matches the current access point (e.g., if the user has accessed the current access point before), then the access information can be used to access the current access point. The way to determine whether the access information that is pre-recorded matches the current access point is to compare the access point name and the access point type in the access information with the name and the type of the current access point. If the two names and the two types are consistent with each other respectively, it means that the matching is successful, and then the access password is input for verification according to the encryption mechanism.
[0034] Step S 14 : saving the current access point into a list.
[0035] The current access point is saved into a list after the current access point has been accessed to make it convenient for the user to view later on. In this embodiment, if the access information does not match the current access point, the current access point is also saved into a list.
[0036] Step S 15 : continuing to search for a next access point, and returning to the step of determining whether any access point is found within a predetermined time.
[0037] Because there are also other access points in the current environment, the user continues to search for a next access point after the current access point has been accessed.
[0038] The wireless connection method of this embodiment suspends the searching after a current access point is found to try connecting to the current access point, and continues to search for other access points after the current access point has been accessed, and also continues to search for other access points even if the current access point fails to be accessed. As compared to the prior art which tries accessing access points one by one only after all the access points have been found, the wireless accessing method of the present disclosure connects to an access point each time the access point is found, which allows access points to be accessed quickly to improve the users' experiences.
[0039] Refer to FIG. 2 , which shows a schematic flowchart diagram of a wireless connection method for a mobile terminal according to a second embodiment of the present disclosure. The wireless connection method comprises the following steps of:
[0040] Step S 201 : beginning to search for an access point in a current environment.
[0041] Step S 202 : determining whether any access point is found within a predetermined time, and if a determination result thereof is yes, proceeding to step S 203 , and if the determination result thereof is no, proceeding to step S 211 .
[0042] When no access point is found, the searching is ended and a prompt is given to the user. This can reduce the power consumption and makes it convenient for the user to know the progress of the searching process.
[0043] Step S 203 : acquiring a current access point that is found and suspending the searching.
[0044] Step S 204 : determining whether access information that is pre-recorded matches the current access point, and if a determination result thereof is yes, proceeding to step S 205 , and if the determination result thereof is no, proceeding to step S 209 .
[0045] Step S 205 : determining whether another access point has been accessed, and if a determination result thereof is yes, proceeding to step S 206 , and if the determination result thereof is no, proceeding to step S 208 .
[0046] In real practice, the user might have already accessed an access point before moving into the current environment, and because the access point is connected wirelessly, the connection with the previous access point may be still remained after the user moved into the current environment. However, the user wants to search in the current environment again to see if there are other available access points. Therefore, after a current access point is found, whether the user has accessed any other access point is determined.
[0047] Step S 206 : determining whether the current access point has a priority level higher than that of the another access point, and if a determination result thereof is yes, proceeding to step S 207 , and if the determination result thereof is no, proceeding to step S 209 .
[0048] After it is determined that the user has accessed an access point, the priority level also needs to be determined. After having found the current access point, the user needs to know the priority level of the current access point to decide whether to replace the access point that has already been accessed with the current access point or not. In this embodiment, the priority level is represented by the signal strength, and a higher signal strength represents a higher priority level.
[0049] Step S 207 : disconnecting the connection with the another access point.
[0050] If the current access point has a priority level higher than that of the another access point, then the connection with the another access point is disconnected.
[0051] Step S 208 : using the access information to access the current access point.
[0052] The access information is used to access the current access point after the connection with the another accessing point is disconnected. The way to access the current access point comprises: automatically matching the access point name, inputting the access password according to the encryption mechanism and so on. The connection reliability can be enhanced by accessing the current access point.
[0053] Step S 209 : saving the current access point into a list.
[0054] No matter whether or not the current access point has been accessed, the current access point will be saved into a list all the same for the user to look up conveniently later on and for quick matching in the next searching process.
[0055] Step S 210 : continuing to search for a next access point, and returning to the step S 202 .
[0056] During the process of searching for a next access point, continue to determine whether any access point is found within a predetermined time so as to try connecting to the next access point. This step can be repeated to find all access points in the current environment.
[0057] Step S 211 : ending the searching
[0058] If no access point is found within the predetermined time, then it is determined that there is no access point in the current environment or all access points have been found. In this case, the searching is ended. In this embodiment, the predetermined time may be set to be 10 seconds.
[0059] Step S 212 : arranging all access points in the list in a descending order according to priority levels thereof.
[0060] All access points are displayed in a list after the searching is ended. In some instances, the access information is not pre-recorded by the user, but the user can manually select an access point and then input the access information to access the access point. After the user has accessed the access point, the access information of the access point will be automatically saved. The access points in the list are arranged in a descending order according to priority levels thereof; and the accessing points having high priority levels are topped to make it convenient for the user to select them first.
[0061] In the wireless connection method of this embodiment, if the user has accessed another access point when a current access point is found and the current access point has a priority level higher than that of the another access point, then the connection with the another access point will be disconnected and the current access point will be accessed by using the access information. Thereby, it is ensured that the user can connect to the access point having the highest priority level in the process of searching for access points to get a reliable connection.
[0062] Refer to FIG. 3 , which shows a schematic structural view of a mobile terminal according to an embodiment of the present disclosure. The mobile terminal comprises a WIFI chip 1 and a baseband-signal processing chip 2 . In this embodiment, the mobile terminal may be a mobile phone or a tablet computer.
[0063] The WIFI chip 1 is configured to search for and access an access point. In this embodiment, the WIFI chip searches for and accesses an access point via a WIFI antenna 11 .
[0064] The baseband-signal processing chip 2 is connected to the WIFI chip 1 . In this embodiment, the baseband-signal processing chip 2 is connected to the WIFI chip 1 via an SDIO bus. The SDIO bus comprises an SDC_CLK wire, an SDC_CMD wire, and an SDC_DATA wire. The SDC_CLK wire is configured to transmit a clock signal, the SDC_CMD wire is configured to transmit a control command, and the SDC_DATA is configured to transmit data. The baseband-signal processing chip 2 comprises a control module 21 , a first determining module 22 , a second determining module 23 and a storage module 24 therein. The storage module 24 is provided with a list.
[0065] The control module 21 is configured to control the WIFI chip 1 to begin to search for an access point in a current environment according to an operation of a user.
[0066] The first determining module 22 is configured to determine whether any access point is found by the WIFI chip 1 within a predetermined time, and if the determination result is yes, notify the storage module 24 to acquire the current access point that is found and notify the control module 21 to control the WIFI chip 1 to suspend the searching.
[0067] The second determining module 23 is configured to determine whether access information that is pre-recorded in the storage module 24 matches the current access point if the determination result of the first determining module is yes, and if the determination result of the second determining module is yes, notify the control module 21 to control the WIFI chip 1 to access the current access point by using the access information and control the WIFI chip 1 to continue to search for a next access point, and notify the storage module 24 to save the current access point into the list.
[0068] The first determining module 22 and the second determining module 23 execute the two determining processes respectively. However, when the baseband-signal processing chip 2 comprises only one determining module, the determining module may be set to execute both the two determining processes.
[0069] In this embodiment, the baseband-signal processing chip 2 also comprises a power-supply management module 25 for supplying power to the WIFI chip 1 .
[0070] According to the above descriptions, the mobile terminal and the wireless connection method thereof of the present disclosure suspend the searching when an access point is found, determine whether access information that is pre-recorded matches the access point, access the access point if the determination result is yes, and then continue to search for a next access point. This allows access points to be accessed quickly by connecting to an access point each time an access point is found. Furthermore, if the user has accessed other access points before accessing a current access point and the current access point has a priority level higher than that of the another access point, the connection with the another access point will be disconnected to access the current access point so that a reliable connection can be ensured.
[0071] What described above are only the embodiments of the present disclosure, but are not intended to limit the scope of the present disclosure. Any equivalent structures or equivalent process flow modifications that are made according to the specification and the attached drawings of the present disclosure, or any direct or indirect applications of the present disclosure in other related technical fields shall all be covered within the scope of the present disclosure. | Disclosed is a wireless connection method for a mobile terminal. The method includes: starting to search for an access point in a current environment; judging whether the access point is found within a preset time, and when rise judgment result is yes, acquiring the found current access point and suspending the search; judging whether the access information recorded in advance matches the current access point, and when the judgment result is yes, recessing the current access point using the access information; storing the current access point in a list; and continuing searching for a next access point, and returning to the step of judging whether an access point is round within a preset time. Also disclosed is a mobile terminal. In this way, the mobile terminal and the wireless connection method therefor of the present invention can rapidly access an access point, improving the user experience. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an exhaust purification device structured by providing a catalyst in an exhaust pipe of a vehicle or the like.
2. Description of the Related Art
In a vehicle such as a two-wheeled motor vehicle and a four-wheeled automobile, a catalyst is provided in an exhaust pipe in order to remove hydrocarbon (HC), nitrogen oxides (NOx), and the like included in exhaust gas. In Japanese Patent Application Laid-open No. 60-17220, there is disclosed a technique in which a catalyst is provided in a muffler of the exhaust pipe of the two-wheeled motor vehicle.
FIG. 8 is a sectional view showing an example of the exhaust pipe provided with the catalyst. The catalyst 100 includes an outer cylinder 102 and a catalyst main body 103 provided in the outer cylinder 102 . The outer cylinder 102 is made of metal such as stainless steel. The catalyst main body 103 is formed by depositing catalyst metal on a surface of a honeycomb structure made of stainless steel or the like. The catalyst main body 103 is secured to an inner face of the outer cylinder 102 by brazing.
In fixing the catalyst 100 to the exhaust pipe 101 , if an outer face of the outer cylinder 102 positioned on an outer periphery side of the catalyst main body 103 is subjected to welding, the brazed portion between the outer cylinder 102 and the catalyst main body 103 is susceptible to heat. Therefore, an end portion 102 A of the outer cylinder 102 is caused to protrude from the catalyst main body 103 along a direction of an axial center O 1 of the catalyst 100 and welding W 5 is applied to this protruding portion, thereby preventing heat from affecting the brazed portion between the outer cylinder 102 and the catalyst main body 103 .
However, if the end portion 102 A of the outer cylinder 102 is caused to protrude from the catalyst main body 103 , there is a useless area that does not contribute to purification of the exhaust gas in the outer cylinder 102 . Therefore, this catalyst is inferior in purification performance to a catalyst in which a catalyst main body is provided throughout an inside of the outer cylinder 102 by an amount corresponding to the useless area.
SUMMARY OF THE INVENTION
The present invention addresses the above described condition, and an object of the present invention is to provide an exhaust purification device in which an entire length of an outer cylinder of a catalyst can be used effectively for exhaust purification and it is possible to prevent heat in fixing of the catalyst to an exhaust pipe from affecting the catalyst.
According to the invention, there is provided an exhaust purification device structured by providing a catalyst in an exhaust pipe, wherein the catalyst includes an outer cylinder and a plurality of catalyst main bodies provided in the outer cylinder in a state of being spaced from each other in an axial direction of the outer cylinder, and an outer face of the outer cylinder positioned between the plurality of catalyst main bodies is a fixed face to be fixed to an inside of the exhaust pipe.
As described above, if the plurality of catalyst main bodies are disposed spaced apart from each other in the outer cylinder, the exhaust gas which has passed through one of the catalyst main bodies is first mixed in the space between the catalyst main bodies and then passes through the other catalyst. Therefore, it is possible to uniformly purify the exhaust gas with the entire length of the catalyst main bodies. Therefore, the catalyst formed by providing the plurality of catalyst main bodies at intervals in the outer cylinder can exert substantially the same performance in spite of smaller amounts of catalyst main bodies as compared with a catalyst formed by providing one catalyst main body throughout an outer cylinder of the same length.
Therefore, in the present invention, the entire length of the outer cylinder can be utilized for purifying the exhaust gas and can exert substantially the same performance as the catalyst formed by providing one catalyst main body throughout the outer cylinder. Moreover, because the catalyst is fixed to the exhaust pipe through the fixed face positioned on the outer periphery side of the space between the plurality of catalyst main bodies, it is possible to prevent heat in fixing of the catalyst to the exhaust pipe from affecting a connection portion between the outer cylinder and the catalyst main bodies.
Preferably, a mounting bracket may be fixed to an inner face of the exhaust pipe and the fixed face may be fixed to the mounting bracket.
In accordance with this structure, a difference between a shape of the inner face of the exhaust pipe and a shape of the outer face of the catalyst can be accommodated by the mounting bracket, thereby properly fixing the catalyst irrespective of an inside shape of the exhaust pipe.
Preferably, the plurality of catalyst main bodies may have different axial lengths and the catalyst main body of the shorter axial length may be disposed at an upstream side of the longer catalyst main body in an exhaust gas flowing direction.
In accordance with this structure, because the exhaust gas of higher temperature circulates through the shorter catalyst main body, it is possible to further promote increase in temperature of the catalyst main body to activate the catalyst main body, thereby enhancing purification efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention will become more clear from the following description taken in conjunction with a preferred embodiment thereof with reference to the accompanying drawings.
FIG. 1 is a plan view of exhaust pipes according to a first embodiment of the present invention.
FIG. 2 is an enlarged sectional view of the exhaust pipe of FIG. 1 .
FIG. 3 is an enlarged sectional view of a fixed portion of a catalyst in the exhaust pipe (an enlarged sectional view of a part III in FIG. 2 ).
FIG. 4 is a plan view of an exhaust pipe according to a second embodiment of the present invention.
FIG. 5 is an enlarged sectional view of a fixed portion of a catalyst in the exhaust pipe (an enlarged sectional view of a part V in FIG. 4 ).
FIG. 6 is a sectional view of an exhaust pipe according to a third embodiment of the present invention.
FIG. 7 is an enlarged sectional view of a fixed portion of a catalyst in the exhaust pipe (an enlarged sectional view of a part VII in FIG. 6 ).
FIG. 8 is a sectional view of a prior-art exhaust pipe.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a plan view of an exhaust purification device according to a first embodiment of the present invention. The exhaust purification device includes two exhaust pipes 11 and the exhaust pipes 11 are connected to respective cylinders of a V-type two-cylinder engine 10 . Each of the exhaust pipes 11 includes a first pipe portion 13 with its front end connected to each of the cylinders of the engine and a second pipe portion 14 connected to a rear end of the first pipe portion 13 . The second pipe portion 14 forms a muffler in which expansion chambers are formed.
FIG. 2 is an enlarged sectional view of a muffler (second pipe portion) 14 . An outer shell of the second pipe portion (the muffler) 14 is formed of an outer cylinder body 16 and an inner cylinder body 17 (i.e. an exhaust pipe 17 ) disposed inside the outer cylinder body 16 . Inside the inner cylinder body 17 , a first expansion chamber 18 , a second expansion chamber 19 , and a third expansion chamber 20 are formed. The muffler 14 is disposed in a front-rear direction and exhaust gas flows front to rear in a direction X in the muffler 14 .
A coupling pipe body 21 is attached to the first expansion chamber 18 . A front portion of the coupling pipe body 21 protrudes forward from the first expansion chamber 18 and is connected to the first pipe portion 13 ( FIG. 1 ). A rear portion of the coupling pipe body 21 is supported on the inner cylinder body 17 through a support plate 23 and a large number of first circulation holes 21 A are formed to penetrate an outer peripheral face of the rear portion. A plurality of openings 23 A are formed in the support plate 23 in a circumferential direction. Therefore, the exhaust gas flowing from the first pipe portion 13 passes through the coupling pipe body 21 , flows into the first expansion chamber 18 through the first circulation holes 21 A, and flows behind the support plate 23 through the openings 23 A in the support plate 23 .
Between the first expansion chamber 18 and the second expansion chamber 19 , a first partition 35 is provided. A catalyst 30 is provided in such a manner as to penetrate the first partition 35 . The exhaust gas flows from the first expansion chamber 18 through the catalyst 30 into the second expansion chamber 19 . The catalyst 30 will be described later.
Between the second expansion chamber 19 and the third expansion chamber 20 , a second partition 24 is provided. A rear end portion of the third expansion chamber 20 is closed with a rear end wall 25 . An intermediate pipe body 26 extending in the front-rear direction is provided to penetrate the second partition 24 and the rear end wall 25 . In the third expansion chamber 20 , the intermediate pipe body 26 is closed with a third partition 27 . A plurality of second circulation holes 26 A are formed in an outer peripheral face of the intermediate pipe body 26 positioned in front of the third partition 27 and in the second expansion chamber 19 . A plurality of third circulation holes 26 B are formed in the outer peripheral face of the intermediate pipe body 26 positioned in front of the third partition 27 and in the third expansion chamber 20 . A plurality of fourth circulation holes 26 C are formed in the outer peripheral face of the intermediate pipe body positioned behind the third partition 27 and in the third expansion chamber 20 .
The exhaust gas that has flowed into the second expansion chamber 19 flows into the intermediate pipe body 26 through the second circulation holes 26 A and flows into the third expansion chamber 20 through the third circulation holes 26 B. Then, the exhaust gas flows into the intermediate pipe body 26 through the fourth circulation holes 26 C and is emitted outside through a rear end opening of the intermediate pipe body 26 .
As shown in FIG. 1 , the two exhaust pipes 11 are connected to each other through a connecting pipe 28 . Respective end portions of the connecting pipe 28 are connected to the first expansion chambers 18 in the mufflers 14 of the respective exhaust pipes 11 as shown in FIG. 2 . In this way, the exhaust gas substantially uniformly flows into the two exhaust pipes 11 .
As shown in FIG. 2 , the catalyst 30 is formed of a cylindrical outer cylinder 31 and catalyst main bodies 32 , 33 disposed in the outer cylinder 31 . The outer cylinder 31 is made of metal such as stainless steel and is disposed with its-axial center O 1 oriented in the front-rear direction (exhaust flowing direction X). The catalyst main bodies 32 , 33 are formed by depositing catalyst metal on surfaces of honeycomb structures made of stainless steel or the like. The catalyst main bodies 32 , 33 are secured to the outer cylinder 31 by brazing.
The two catalyst main bodies 32 , 33 are arranged side by side along the direction of the axial center O 1 (axial direction) of the outer cylinder 31 and a space S is formed between them. The catalyst main body 32 on the front side (upstream side of the exhaust flowing direction X) is formed to be shorter than the catalyst main body 33 on the rear side (downstream side). A front end of the front catalyst main body 32 is substantially aligned with a front end of the outer cylinder 31 and a rear end of the rear catalyst main body 33 is substantially aligned with a rear end of the outer cylinder 31 .
The catalyst 30 is fixed inside the muffler 14 through the first partition 35 . In other words, the first partition 35 also functions as a mounting bracket for fixing the catalyst 30 to the muffler 14 . FIG. 3 is an enlarged sectional view of a fixed portion of the catalyst 30 . The first partition bracket (the mounting bracket) 35 is formed of an outer cylinder portion 35 A disposed along an inner face of the inner cylinder body 17 of the muffler 14 , an inner cylinder portion 35 B disposed along an outer face of the outer cylinder 31 of the catalyst 30 and displaced at a position apart from the outer cylinder portion 35 A in the direction of the axial center O 1 and in a radial direction, and a connecting cylinder portion 35 C inclined to connect adjacent end portions of the outer cylinder portion 35 A and the inner cylinder portion 35 B. The outer cylinder portion 35 A, the inner cylinder portion 35 B, and the connecting cylinder portion 35 C are formed integrally.
A plurality of through holes 17 A are formed in a portion of the inner cylinder body 17 which the outer cylinder portion 35 A of the mounting bracket 35 overlaps. By applying plug welding W 1 into the through holes 17 A, the outer cylinder portion 35 A is fixed to the inner face of the inner cylinder body 17 .
The outer face of the outer cylinder 31 of the catalyst 30 is fixed to the rear end of the inner cylinder portion 35 B of the mounting bracket 35 by fillet welding W 2 in a plurality of positions in the circumferential direction. A portion (fixed face) 31 A of the outer face of the outer cylinder 31 where the welding W 2 is applied is positioned on an outer periphery side of the space S between the front and rear catalyst main bodies 32 , 33 .
Therefore, the present embodiment performs and exerts the following functions and effects.
(1) The space S is formed between the two catalyst main bodies 32 , 33 and the portion (fixed face) 31 A of the outer face of the outer cylinder 31 positioned on the outer periphery side of the space S is fixed to the inner face of the muffler 14 through the mounting bracket 35 . Therefore, heat of welding W 2 is less likely to be transferred to the brazed portion between the outer cylinder 31 and the catalyst main bodies 32 , 33 and it is possible to reduce the influence of the heat on the brazed portion.
(2) Because the catalyst 30 is fixed to the muffler 14 through the mounting bracket 35 , a shape of the catalyst 30 does not necessarily require to be adapted to an inside shape of the muffler 14 and the mounting bracket 35 is adaptable to the inside shape of the muffler 14 . Therefore, the catalyst 30 can be fixed properly irrespective of the inside shape of the muffler 14 .
(3) If one catalyst main body is provided in the outer cylinder as in the prior art, the exhaust gas flows through the same cell of the honeycomb from start to finish. Therefore, depending on temperature distribution, gas distribution, and the like in the catalyst main body, unevenness may develop in such a manner that purification is finished in one cell of the honeycomb while little progress has been made with purification in another cell of the honeycomb. In the catalyst 30 of the present embodiment, because the two catalyst main bodies 32 , 33 are disposed with a clearance (space S) between them, the exhaust gas which has passed through the front catalyst main body 32 and has been purified is once mixed in the space S and then flows into the rear catalyst main body 33 and is purified again. Therefore, it is possible to purify the exhaust gas without causing unevenness by using the two catalyst main bodies 32 , 33 , thereby enhancing purification efficiency.
In general, in the outer cylinders of the same length, one of which is provided with one catalyst main body throughout the length of the outer cylinder and the other of which is provided with two catalyst main bodies 32 , 33 with the space S between them will have substantially the same performance. Therefore, in the catalyst 30 of the present embodiment, it is possible to reduce amounts of the catalyst main bodies 32 , 33 by an amount corresponding to the space S, thereby reducing the cost.
(4) Because the catalyst 30 is disposed in the front portion of the muffler 14 , it is possible to circulate the exhaust gas of relatively high temperature, thereby promoting increase in temperature of the catalyst 30 so as to activate the catalyst 30 .
(5) In the catalyst 30 , because the front catalyst main body 32 is formed to be shorter than the rear catalyst main body 33 , it is possible to further promote increase in temperature of the front catalyst main body 32 through which the exhaust gas of the higher temperature circulates to activate the catalyst main body 32 , thereby enhancing the purification efficiency.
FIG. 4 is a plan view of a second embodiment of the present invention. Although the example in which the catalyst 30 is provided in the expansion chamber 19 of the muffler 14 has been shown in the first embodiment, an example in which the catalyst 30 is disposed in the exhaust pipe 11 before the muffler is shown in the present embodiment. An exhaust pipe 11 of the present embodiment is used for a parallel four-cylinder engine 10 and includes four first pipe portions 41 connected to exhaust ports of respective cylinders of the engine 10 , two first collecting pipes 42 for collecting four of the first pipe portions 41 into two, two catalyst pipes 43 connected to the respective first collecting pipes 42 , a second collecting pipe 44 for collecting the two catalyst pipes 43 into one, and a second pipe portion 45 connected to the second collecting pipe 44 . A branch pipe, a muffler, and the like (not shown) are connected to the second pipe portion 45 .
A catalyst 30 is disposed in each of the catalyst pipes 43 . The catalyst 30 of the present embodiment is also formed of an outer cylinder 31 and two catalyst main bodies 32 , 33 provided in the outer cylinder 31 . However, two catalyst main bodies 32 , 33 have substantially the same length and a space S is formed in a central portion in an axial direction of the outer cylinder 31 . The respective catalyst main bodies 32 , 33 are brazed to the outer cylinder 31 through brazing foils 77 disposed at substantially central portions of outer peripheral faces of the catalyst main bodies 32 , 33 in the direction of the axial center O 1 .
FIG. 5 is an enlarged sectional view of a fixed portion of the catalyst 30 . The mounting bracket 35 as used in the first embodiment ( FIG. 2 ) is not used in the present embodiment and the catalyst 30 is directly mounted to the exhaust pipe (catalyst pipe 43 ). A portion 31 A of an outer face of the outer cylinder 31 positioned on the outer periphery side of the space portion S of the catalyst 30 is used as a fixed face of the outer cylinder 31 as in the first embodiment and a plurality of through holes 43 A are formed in a plurality of positions in a circumferential direction of the catalyst pipe 43 in contact with the fixed face. The catalyst 30 is fixed to the catalyst pipe 43 by applying plug welding W 3 into the through holes 43 A. Therefore, the present embodiment also performs and exerts the same functions and effects as the first embodiment.
FIG. 6 is a sectional view of an exhaust pipe 11 according to a third embodiment of the present invention. The exhaust pipe 11 of the present embodiment is a muffler having expansion chambers and a catalyst 30 is provided in this muffler 11 . An outer shell of the exhaust pipe (the muffler) 11 is formed of an outer cylinder body 51 and an inner cylinder body 52 and opposite ends of the outer cylinder body 51 in a direction of an axial center are closed with a front end wall 53 and a rear end wall 54 . Inside the inner cylinder body 52 , a first expansion chamber 56 , a fourth expansion chamber 57 , a third expansion chamber 58 , and a second expansion chamber 59 are disposed in this order from front and the respective expansion chambers 56 , 57 , 58 , and 59 are separated by first, second, and third partitions 60 , 61 , and 62 .
A first communicating pipe 63 for communicating with the first expansion chamber 56 and the second expansion chamber 59 penetrates the first, second, and third partitions 60 , 61 , and 62 . A second communicating pipe 64 for communicating with the third expansion chamber 58 and the fourth expansion chamber 57 penetrates the second partition 61 . Moreover, a discharge pipe 65 penetrates the second and third partitions 61 , 62 , and the rear end wall 54 . An end portion of the discharge pipe 65 opens in the fourth expansion chamber 57 and the other end portion opens in the rear end wall 54 . The third partition 62 is formed with a communicating hole (not shown) for communicating with the second expansion chamber 59 and the third expansion chamber 58 .
A catalyst 30 is provided in the inner cylinder body 52 . The catalyst 30 is provided in such a manner as to penetrate the first, second, and third partitions 60 , 61 , and 62 and is directly supported by the partitions 61 , 62 , and 63 . One end portion of the catalyst 30 is disposed in the first expansion chamber 56 . A delivery pipe 70 having a large number of circulation holes 70 A on an outer peripheral face thereof is mounted to the one end portion of the catalyst 30 . The other end portion of the catalyst 30 is disposed in the second expansion chamber 59 and one end of a curved pipe 71 curved into a U shape is connected to the other end portion. The other end of the curved pipe 71 is connected to an inflow pipe 72 . The inflow pipe 72 is provided in such a manner as to penetrate the front end wall 53 , the first, second, and third partitions 60 , 61 , and 62 .
Into the muffler 11 of the present embodiment, the exhaust gas flows from the one end of the inflow pipe 72 . Then, the exhaust gas passes from the curved pipe 71 through the catalyst 30 and flows into the first expansion chamber 56 through the circulation holes 70 A in the delivery pipe 70 . Then, the exhaust gas flows from the first expansion chamber 56 into the second expansion chamber 59 through the first communicating pipe 63 , flows from the second expansion chamber 59 into the third expansion chamber 58 through the communicating hole (not shown), flows from the third expansion chamber 58 into the fourth expansion chamber 57 through the second communicating pipe 64 , and is discharged outside from the fourth expansion chamber 57 through the discharge pipe 65 .
The catalyst 30 is formed of an outer cylinder 31 and two catalyst main bodies 32 , 33 . Between the two catalyst main bodies 32 , 33 , a space S is formed. In this point, the embodiment is similar to the above-described first and second embodiments. The catalyst main body 32 on an upstream side of an exhaust flowing direction X is formed to be shorter than the catalyst main body 33 on the downstream side. A portion 31 A of an outer face of the outer cylinder 31 positioned on an outer peripheral side of the space S between the two catalyst main bodies 32 , 33 is used as a fixed face of the outer cylinder 31 and fixed to the second partition 61 by welding.
FIG. 7 is an enlarged sectional view of a fixed portion of the catalyst 30 . The outer cylinder 31 of the catalyst 30 penetrates a hole 61 A formed in the second partition 61 . A peripheral edge portion of the hole 61 A is bent in the exhaust flowing direction X. The peripheral edge portion of the hole 61 A and the portion (the fixed face) 31 A of the outer face of the outer cylinder 31 are fixed to each other in a plurality of positions in a circumferential direction by welding W 4 .
The present embodiment also performs and exerts the same functions and effects as the first embodiment. By providing the catalyst 30 in such a manner that the catalyst 30 penetrates the partition 61 separating the plurality of expansion chambers in the muffler 11 as in the present embodiment, it is possible to fix the catalyst 30 by using the partition 61 as a mounting bracket.
(1) Although the two catalyst main bodies 32 , 33 are provided in the outer cylinder 31 in the catalyst 30 in the above embodiments, three or more catalyst main bodies may be provided.
(2) The plurality of catalyst main bodies 32 , 33 may have the same or different purification performance (such as size of cells of the honeycomb).
(3) The present invention can be utilized effectively as an exhaust purification device of vehicles such as a two-wheeled motor vehicle and a four-wheeled automobile, a working machine, industrial machine, or the like.
Although the invention has been described in its preferred embodiments with a certain degree of particularity, obviously many changes and variations are possible therein. It is therefore to be understood that the present invention may be practical otherwise than as specifically described herein with out departing from the scope and spirit thereof. | Disclosed is an exhaust purification device in which an entire length of an outer cylinder of a catalyst can be used effectively for exhaust purification and it is possible to prevent heat in fixing of the catalyst to an exhaust pipe from affecting a connection portion between the outer cylinder and catalyst main bodies. A catalyst includes an outer cylinder and a plurality of catalyst main bodies provided in the outer cylinder in a state of being spaced each other in a direction of an axial center of the outer cylinder. An outer face of the outer cylinder positioned between the catalyst main bodies is a fixed face to be fixed to an inside of the exhaust pipe. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of and claims a benefit of priority under 35 USC §119, based on U.S. patent application Ser. No. 12/813,770, filed Jun. 11, 2010 now published as U.S. Publication No. 2011/0305551, the entire contents of which are hereby expressly incorporated by reference into the present application.
BACKGROUND OF THE INVENTION
Devices for road widening and creating shoulders are known in the road construction industry. Many of the devices are designed for use only on either the right side of the road or the left side of a road. Oftentimes different machines must be kept on the construction site for road construction on the left and right sides of the road or the machine must be driven in a different direction. This not only increases construction costs by necessitating multiple machines, but also increases construction time as well.
U.S. Pat. No. 7,540,687, the entire contents of which are expressly incorporated for reference, discloses the use of hydraulics for movement of aggregate-spreading systems. The hoses in these hydraulic systems may be prone to leaks and failure over time which requires maintenance and cleaning of the machine. Additionally, hydraulics can be difficult to control when precise, fine adjustments are necessary. Hydraulic fluid, hoses, and pistons also add considerable weight to the existing devices.
Another feature of known devices is that they are self-propelled. Many of the devices include large engines with transmissions for moving the device. This adds considerable costs as well as weight to the device.
What is therefore needed in the road construction industry is a low-cost device that may be either pushed by another vehicle such as a skid steer or attached to a rear end of an aggregate storage vehicle such as a dump truck, thus eliminating the need for an engine and drivetrain. Also needed is a device that eliminates hydraulics and utilizes electronic actuators and electronic motors for operation of the device. Another feature needed is a device that is constructed in a lightweight design, allowing for easier mobility, repairs, and maintenance.
SUMMARY AND OBJECTS OF THE INVENTION
One object of the invention is to provide an aggregate-spreading device that may be attached either to a vehicle such as a skid steer and pushed behind a dump truck or suspended directly to the rear of a vehicle such as a dump truck, allowing the aggregate-spreading device to receive aggregate from the dump truck.
In accordance with one object of the invention, a spreader assembly may be attached on either both sides of the device or on a single side. The spreader assemblies are configured to extend and retract to and from the device and also may pivot allowing an angular adjustment. This movement may be accomplished with the use of electronic actuators, allowing an operator to have precise control over the width and depth of the aggregate that is spread.
In accordance with another aspect of the invention, a conveyor may be controlled with the controller to rotate in one direction for supplying aggregate to a spreader assembly on one side of the device, and controlled to reverse the rotation so as to supply aggregate to a spreader assembly on the opposite side of the device. This allows for the same device to be used when spreading aggregate on either side of the road while operating the machine in any desired direction.
In accordance with yet another aspect of the invention, the device is constructed on a skeletal frame with various components attaching to the frame including a height adjustable hopper. This allows for a modular construction and assists maintenance and repair work as various components may be removed or replaced with ease. Manufacturing costs are also lowered as is the overall weight of the device.
Another object of the invention is to provide an apparatus that has one or more of the characteristics discussed above in various combinations, thus, allowing for a reduced labor time and labor effort when spreading aggregate on a job site. These and other aspects and objects of the present invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following description, while indicating preferred embodiments of the present invention, is given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.
BRIEF DESCRIPTION OF THE DRAWINGS
A clear conception of the advantages and features constituting the present invention and of the construction and operation of typical mechanisms provided with the present invention, will become more readily apparent by referring to the exemplary, and therefore non-limiting, embodiments illustrated in the drawings accompanying and forming a part of this specification, wherein like reference numerals designate the same elements in the several views, and in which:
FIG. 1 illustrates an orthogonal view of the inventive aggregate-spreading device with a dual spreader assembly;
FIG. 2 illustrates a back view of the aggregate-spreading device of FIG. 1 ;
FIG. 3 illustrates a front view of the aggregate-spreading device of FIG. 1 ;
FIG. 4 illustrates a side view of the aggregate-spreading device of FIG. 1 ;
FIG. 5 illustrates a top view of the aggregate-spreading device of FIG. 1 ;
FIG. 6 illustrates a bottom view of the aggregate-spreading device of FIG. 1 ;
FIG. 7 illustrates another orthogonal view of the aggregate-spreading device of FIG. 1 ;
FIG. 8 illustrates an orthogonal view of a conveyor drive unit assembly of the invention;
FIG. 9 illustrates an orthogonal view of the skeletal frame for an aggregate-spreading machine with a single spreader assembly;
FIG. 10 illustrates an orthogonal view of the aggregate-spreading device equipped with a single spreader assembly;
FIG. 11 illustrates a bottom view of the aggregate-spreading device of FIG. 10 ;
FIG. 12 illustrates a back view of the aggregate-spreading device of FIG. 10 ;
FIG. 13 illustrates a front view of the aggregate-spreading device of FIG. 10 ;
FIG. 14 illustrates a top view of the aggregate-spreading device of FIG. 10 ;
FIG. 15 illustrates an orthogonal view of the aggregate-spreading device of FIG. 1 in operation while attached to a skid steer; and
FIG. 16 illustrates an orthogonal view of the aggregate-spreading device of FIG. 1 in operation while attached to a rear end of a dump truck.
In describing the preferred embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the words “connected”, “attached”, or terms similar thereto are often used. They are not limited to direct connection but include connection through other elements where such connection is recognized as being equivalent by those skilled in the art.
DESCRIPTION OF EMBODIMENTS
1. Overview
The present invention is directed to a device for spreading aggregate such as gravel on the side of the road. An effect of the present invention is to allow a road construction crew to widen or create a shoulder or road while minimizing the amount of time and labor required. One aspect of the invention is to provide an apparatus that is constructed on a skeletal frame and incorporates electronic motors and electronic actuators. Such an apparatus has the ability to spread aggregate all while being controlled with a manual controller that may be located remotely. The manual controller controls the electronics including electronic actuators and electronic motors to vary a conveyor speed, vary the conveyor's rotation direction, and control movement of the spreader assemblies.
An aggregate-spreading device is disclosed with a first and a second spreader assembly. The aggregate-spreading device is built on a skeletal frame. A hopper, for receiving an aggregate from a vehicle such as a dump truck is attached to the skeletal frame by a single hopper support bar for receiving the aggregate. Aggregate is understood to include a multitude of construction materials including, but not limited to, gravel, sand, soil, stone, hot asphalt, crushed cement, wet cement, and any other material used to construct roads. A tailgate stop extends from the support bar for limiting the dump truck's tailgate from over-extending and spilling aggregate onto undesired locations. A tailgate stop prevents the tailgate of the dump truck from opening beyond a desired amount and assures that aggregate is only supplied into the hopper. The hopper is constructed of a front wall, a back wall, and a cutout wall on each side of the hopper. The cutout walls include a cutout. A conveyor drive unit assembly is attached to the skeletal frame at either end of the conveyor, or may be attached at both ends of the conveyor, by threaded rods that attach to insertion points. This allows the conveyor drive unit assembly to be positionable, varying the tension of the conveyor. The conveyor drive unit assembly drives the conveyor in a rotating motion. The conveyor rotates by wrapping around conveyor drive which is made up of a plurality of T-shaped extensions that converge on a single roller that is supported by a bearing on each end of the single roller. The conveyor drive is rotated by a conveyor motor. The conveyor motor may transfer rotating motion directly to the single roller with a chain that attaches to the single roller in between a first bearing plate and a second bearing plate. The conveyor rotates surrounding a path that includes a plurality of rollers that are supported on the skeletal frame by roller mounts. The conveyor motor may also be a reversible motor that rotates the conveyor, plurality of rollers, and conveyor drive in a first direction and may reverse rotation to rotate the conveyor in a second direction. This allows aggregate to be delivered to either side of the aggregate-spreading device. A conveyor shield protects the edges of the conveyor. A chain shield protects the chain from any foreign objects. A first spreader assembly attached to a first end of the skeletal frame may be extended to and from the skeletal frame for controlling how wide aggregate will be spread from the skeletal frame. A second spreader assembly attaches to a second end of the skeletal frame opposite the first end and also includes a variable extension distance from the skeletal frame.
The aggregate-spreading device may be controlled by any electronic device, preferably a controller in communication with the conveyor motor, the first spreader assembly, and the second spreader assembly. The aggregate-spreading device may also be equipped with either hydraulics, electronic actuators, or a combination thereof for controlling the movement of the spreader assemblies. The controller may operate in a wireless fashion and be located inside a dump truck that supplies aggregate to the aggregate-spreading device, inside a vehicle such as a skid steer that pushes the aggregate-spreading device, or anywhere an operator may wish to be while controlling the device. The controller is preferably operated by a user with manual inputs and may be mounted inside the skid steer or dump truck or simply handheld. The controller may be operated to control the rotation of the conveyor to supply aggregate to the first spreader assembly when rotating in one direction and supply aggregate to the second spreader assembly when rotating in the opposite direction, control the conveyor rotation speed, and also control movement of the spreader assemblies. The controller controls the aggregate-spreading assemblies by communicating with a plurality of electronic actuators. The electronic actuators provide power to pistons that extend the aggregate-spreading assemblies to and from the skeletal frame and also provide an angular adjustment.
The pistons are controlled in order to determine the width and depth of the distributed aggregate. The controller and electronic actuators control the spreader assemblies so that they may be moved in multiple directions. For example, each spreader assembly is equipped with a piston, chain, and angular adjustment guide. The first spreader assembly includes a first spreader plate, a first spreader extension connected to the first spreader plate at approximately a right angle, a first chain attaching an end of the spreader plate to the skeletal frame, a first piston, and an angular adjustment guide. Also included in the second spreader assembly is a second spreader plate, a second piston, a second chain, an angular adjust guide, and a second spreader extension.
As aggregate is delivered into the hopper, it falls onto the conveyor which delivers the aggregate to either the first spreader assembly or the second spreader assembly depending on the inputs provided to the controller by an operator. As the aggregate is supplied to either one of the spreader assemblies, the spreader assemblies may be moved in a manner placing the first or second spreader plate closer or further away from the skeletal frame by extending or retracting the piston with input to the controller, and the spreader assemblies may be adjusted with an angular adjustment. This angular adjustment allows the spreader assemblies to tilt in the vertical direction so that the first spreader plate or the second spreader plate is closer or further away from the ground. The angular adjustment guides provide a maximum and a minimum adjustment distance as well. The first and second chains are attached to the skeletal frame and may be attached to the first or second spreader plates to provide additional support under the weight of supplied aggregate and the weight of the extended spreader assemblies themselves.
As discussed above, the aggregate-spreading device may be fastened to the front of a vehicle such as a skid steer but may optionally be fastened to any vehicle and pushed behind a dump truck. Contact rollers attached to the skeletal frame on the front side of the aggregate-spreading device are designed to allow contact with the rear wheels of the dump truck and rotate when in contact. Alternatively, the aggregate-spreading device may also be attached directly to the rear end of a dump truck by attaching the auxiliary mounting plate to any attachment point on the rear end of the dump truck, such as a trailer hitch. The aggregate-spreading device also has a set of wheels allowing it to roll on the road as it is suspended behind the dump truck or pushed by a skid steer. Attaching the aggregate-spreading device directly to the rear of a dump truck eliminates the need for an additional vehicle and also lowers the labor force required to widen roads and spread aggregate.
The skeletal frame of the aggregate-spreading device is strengthened by attachment of a plurality of plates to form an exterior skin on the skeletal frame. The plates include, for example, a front plate and extension; however, any number of plates may be attached to the skeletal frame. The plurality of plates provide structural support to the skeletal frame, and because they may be removed and re-attached, they allow for simplified repairs, simplified assembly operations, and simplified maintenance operations as compared to other construction machines that do not include a skeletal frame and plate construction.
A similar aggregate-spreading device is also disclosed, however, it is equipped with a single spreader assembly on a single end of the device. The device with a single spreader assembly functions identically to the device discussed above, but simply has a single spreader assembly. As there is only one spreader assembly, the conveyor only delivers aggregate to that side of the device. The hopper also includes one cutout wall with the cutout on the side of the device with the spreader assembly. The spreader assembly is similarly equipped with a spreader plate, spreader extension, piston, and chain, and operates identically to the spreader assemblies discussed above.
2. Detailed Description
The present invention and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments described in detail in the following description.
Beginning with FIG. 1 , an aggregate-spreading device 1 is disclosed. The aggregate-spreading device 1 is constructed on a skeletal frame 10 with a plurality of plates attached to the exterior of the skeletal frame 10 , including a front plate 33 and an extension 50 , however, any number of additional plates may also be attached to the skeletal frame for increased rigidity and protection from damage. Also attached to the skeletal frame 10 by a hopper support bar 12 , better seen in FIG. 2 , is a hopper 5 . The hopper 5 is constructed out of a back wall 7 , a front wall 6 , and cutout walls 9 . The cut out walls 9 each includes a cutout 4 . The hopper 5 is configured for receiving aggregate and delivering it to a conveyor 30 below. Aggregate is understood to include a multitude of construction materials including, but not limited to, top soil, wet concrete, hot asphalt, sand, gravel, crushed concrete, recycled materials, stone, and any other material used in road construction. A conveyor shield 32 guards the edge of the conveyor 30 and a chain shield 31 protects the conveyor's drive chain. The aggregate-spreading device 1 may be attached to the front of the vehicle, for example a skid steer 61 , and pushed from behind with the use of a universal mount 45 as shown in FIG. 15 . In this configuration, the skid steer pushes the aggregate-spreading device 1 behind the dump truck 59 that supplies aggregate to the hopper 5 . A pair of contact rollers 55 is designed to contact the rear wheels of the aggregate-supplying vehicle and to rotate along with the rear wheels of the vehicle. Alternatively, the auxiliary mounting plate 53 attached to the front of the aggregate-spreading device 1 may engage with the rear of the aggregate-supplying vehicle, for example a dump truck 59 , suspending the aggregate-spreading device 1 aggregate-supplying vehicle, as shown in FIG. 16 . This alternative configuration eliminates the need for an additional vehicle to push the aggregate-spreading device 1 . A pair of wheels 60 allows the aggregate-spreading device to roll along the ground as it moves; however, any number of wheels may be attached to the device for added support. The second spreader assembly 25 is also visible and is configured to spread aggregate that is supplied from the conveyor 30 . The second spreader assembly 25 includes a second spreader plate 26 , a second spreader extension 29 that is attached to the second spreader plate 26 at a right angle, and a second chain 28 . The second chain 28 is attached to the skeletal frame 10 on one end and the may be attached to the second spreader plate 26 at any other in order to provide additional support to the second spreader plate 26 under the load of aggregate.
Looking now at FIG. 2 , the aggregate-spreading device 1 is shown from the rear. The hopper 5 is attached to sleeve hopper support bar 12 on the skeletal frame 10 . Proximate to the hopper support bar 12 is a tailgate stop 11 which prevents a dump truck's tailgate from opening beyond a desired amount as it supplies aggregate to the hopper. This limits the aggregate to being supplied only to the hopper and not to the surrounding areas. Both spreader assemblies, first spreader assembly 20 , and second spreader assembly 25 , are visible. First spreader assembly 20 is identical to the second spreader assembly 25 except it is attached to the opposite side of the skeletal frame 10 . The first spreader assembly also includes a first piston 22 that can extend and retract the first spreader plate 21 to and from the skeletal frame 10 . A first chain 23 is attached to the skeletal frame 10 and may be attached to the first spreader 21 anywhere in between the first end and the second end for supporting the weight of the first spreader assembly when extended. Second spreader assembly 25 also includes a second piston 27 that is configured to extend and retract the second spreader plate 26 to and from the skeletal frame 10 . Both spreader assemblies 20 , 25 may be adjusted to include an angular adjustment 19 that pivots the spreader assemblies 20 , 25 about a central axis of the aggregate-spreading device 1 , allowing the first spreader plate 21 and the second spreader plate 26 to have adjustable heights from the ground. The slope attachments 13 allow attachment of a ratcheting device from the slope attachment 13 to either spreader assembly 20 , 25 to reinforce the positioning of the angular adjustment 19 . An angular adjustment guide 47 on both the first spreader assembly 20 and the second spreader assembly 25 controls the maximum and minimum angular adjustment. The universal mount 45 is also shown and is configured to attach to a vehicle for pushing the aggregate-spreading device 1 behind a vehicle that supplies the hopper 5 with aggregate.
Referring now to FIG. 3 , the front side of the aggregate-spreading device 1 may be seen. The hopper 5 is suspended above the skeletal frame 10 by the hopper support bar 12 . The front plate 33 not only reinforces the skeletal frame 10 but also provides a mounting location for both contact rollers 55 and auxiliary mounting plate 53 . The first spreader assembly 20 and the second spreader assembly 25 receive aggregate delivered to the aggregate-spreading device 1 and are controlled to extend, retract, and adjust in an angular direction with the use of a controller 57 seen in FIGS. 15 and 16 . The controller 57 may be wired to the aggregate-spreading device 1 but is preferably a wireless controller, allowing the controller to be located in the aggregate-supplying vehicle or in the vehicle pushing the aggregate-spreading device 1 .
Turning now to FIG. 4 , the aggregate-spreading device 1 is shown from the side. The hopper 5 includes a cutout 4 on the cutout wall 9 . The cutout 4 may be covered or opened to assist aggregate to spill to the desired spreader assembly. A slope attachment 13 allows attachment of a ratcheting device from the slope attachment 13 to either spreader assembly for assisting in making the angular adjustment 19 discussed above. The hopper 5 is attached to the skeletal frame 10 by a single point by the hopper support bar 12 . The tailgate stop 11 is extendable and limits the motion of a dump truck's tailgate. FIG. 5 shows an overhead view of the aggregate-spreading device 1 . The hopper 5 is suspended directly over the conveyor 30 . The conveyor 30 is chain driven to rotate in both directions. This allows the conveyor 30 to supply aggregate to the second spreader assembly 25 when rotating in one direction and to supply aggregate to the first spreader assembly 20 when rotating in the opposite direction. The rotational direction of the conveyor 30 is controlled by the controller 57 . Chain shields 31 and conveyor shields 32 protect the edges of the conveyor 30 and of the chain, which is not pictured.
FIG. 6 shows a bottom view of the aggregate-spreading device 1 . The rotation of the conveyor 30 is powered by a conveyor motor 56 . The conveyor motor 56 is directly controlled by the controller 57 . This allows the operator to control the rotational direction of the conveyor 30 from any location. The conveyor 30 is supported by and assisted in rotating with the help of a plurality of rollers 41 that are attached to the skeletal frame 10 on each end. The rollers 41 are preferably ball bearing rollers to minimize friction and assist the conveyor 30 in rotating. The rotation of the conveyor 30 is powered and made possible by a conveyor drive unit assembly 35 , shown in detail in FIG. 8 , located at each end of the conveyor 30 . The rollers 41 and conveyor motor 56 attach to the skeletal frame by interlocking with a plurality of roller mounts 43 , seen in FIG. 9 , that are located on the skeletal frame 10 at each end of the rollers 41 and conveyor motor 46 . The aggregate-spreading device 1 is equipped with a plurality of electronic actuators 54 for moving the first spreader assembly 20 and the second spreader assembly 25 . Electronic actuators 54 control the first piston 22 and the second piston 27 along with the angular adjustment 19 to allow an operator precise control over any movement of the spreader assemblies 20 , 25 with the use of the controller 57 .
FIG. 7 shows an orthographic view of the aggregate-spreading device 1 . Both of the first spreader assembly 20 and the second spreader assembly 25 can be seen. Angular adjustment guides 47 prevent over adjustment in the angular direction of the first and second spreader assemblies 20 , 25 . A front plate support 34 acts as a truss and supports the skeletal frame 10 under the load of aggregate or when being pushed from behind or suspended from an aggregate spending vehicle. While only a single front plate support 34 is seen, there are many more front plate supports, as seen in FIG. 9 .
Moving on to FIG. 8 , the conveyor drive unit assembly 35 is shown. The conveyor drive unit assembly 35 is attached to the skeletal frame 10 with a pair of threaded rods 39 for securing the drive unit assembly to the skeletal frame 10 . The conveyor drive unit assembly 35 is attached to skeletal frame 10 on any side proximate to a spreader assembly. The conveyor drive unit assembly 35 includes a conveyor drive 40 that is made up of a plurality of T-shaped extensions that extend from a central axis of the conveyor drive 40 and converge on a single roller 48 to form a rotating drum. The single roller 48 has a bearing 36 on each end to assist in rotation. A first bearing plate 37 and a second bearing plate 38 on the ends of the single roller 48 assist in supporting the load of the conveyor drive 40 . A chain may be used to rotate the conveyor drive 40 . The chain interacts with a gear in between the first bearing plate 37 and the second bearing plate 38 that is attached to the single roller 48 .
FIG. 9 shows an orthographic view of the skeletal frame according to one embodiment of the invention. While the skeletal frame disclosed in FIG. 9 is very similar to the skeletal frame of the aggregate-spreading device disclosed in FIGS. 1-7 above, it is equipped for a single spreader assembly 14 , shown in FIGS. 10-14 . The concept is identical to the skeletal frame of the dual spreader assembly design disclosed in FIGS. 1-7 . The only difference in the skeletal frame 10 design for the dual spreader assembly aggregate-spreading device is that the spreader attachment 3 as seen in FIG. 9 would be on both sides of the skeletal frame 10 , along with another angular adjustment guide 47 and electronic actuator 54 . As the skeletal frame 10 shown in FIG. 9 has a single-spreader attachment 3 , the conveyor drive assembly mount 44 may be seen on the opposite side. The conveyor drive assembly mount 44 allows for simple attachment of the conveyor drive unit assembly 35 to the skeletal frame 10 . Mount bars 39 are inserted into the mount insertion point 42 for positive retention and location of the conveyor drive unit assembly 35 to the skeletal frame 10 . A plurality of front plate supports 34 functions as trusses to support the load on the skeletal frame 10 when the device is in use. The skeletal frame 10 also allows for easy repair and maintenance work to the aggregate-spreading device 1 as all the components may be removed from the skeletal frame 10 . The skeletal frame 10 also makes the aggregate-spreading device 1 much lighter in weight as compared to previous devices that did not incorporate a skeletal frame 10 .
FIG. 10 shows an orthographic view of an aggregate-spreading device 1 that includes a single spreader assembly 14 . As there is only one spreader assembly 14 , the side of the aggregate-spreading device 1 is exposed and other features may be seen. For example, the conveyor drive unit assembly 35 can be seen along with a threaded rod 39 that is attached to a threaded rod insertion point 42 . While only a single conveyor drive unit assembly 35 is seen, all aggregate-spreading devices 1 optimally are equipped with a conveyor drive unit assembly 35 on each end of the conveyor 30 . A side plate 52 strengthens the skeletal frame 10 and prevents aggregate from falling off the conveyor 30 on the side of the aggregate-spreading device 1 that does not include a spreader assembly 14 . A back plate 51 and extension 50 also strengthen the skeletal frame 10 . In all embodiments of the aggregate-spreading device 1 , the various plates strengthening the skeletal frame may be removed and reattached in order to assist maintenance, repair, and cleaning of the aggregate-spreading device 1 . The spreader assembly 14 may be extended to and from the skeletal frame 10 with the use of piston 16 . The piston 16 may also angularly adjust 19 the spreader assembly 14 exactly as is shown and discussed in FIG. 2 and above. An angular-adjustment guide 47 is equipped to prevent over adjusting when making angular adjustments.
Turning to FIG. 11 , a bottom view of the aggregate-spreading device 1 with a single spreader assembly 14 is shown. Just as in the dual spreader assembly embodiment, a plurality of rollers 41 assists the conveyor 30 in rotating. A conveyor motor 56 provides power to rotate the conveyor 30 preferably with the use of the chain attaching to the conveyor drive unit assembly 35 . An electronic actuator 54 powers the movements of the spreader assembly 14 just as disclosed in the dual spreader assembly embodiment above. Electronic actuator 54 is controlled by a controller 57 that is preferably wireless and is also in communication with the conveyor motor 56 to control all functions of the conveyor motor and movement of the spreader assembly 14 with manual input from the operator. As the controller 57 may be located anywhere, an operator may manually control the functions of the aggregate-spreading device 1 from a vehicle pushing the device from the rear or, alternatively, for a vehicle supplying aggregate to the aggregate-spreading device 1 in the front. The aggregate spring device 1 may be attached to the vehicle in front of the device via auxiliary mounting plate 53 , suspending the aggregate-spreading device 1 from the rear of the vehicle. Alternatively, the aggregate-spreading device 1 may be attached to a vehicle pushing the device from the rear by attaching a vehicle to the universal mount 45 . This optional configuration allows the aggregate-spreading device 1 as disclosed in FIGS. 1-7 or in FIGS. 10-14 to be attached to the rear end of a dump truck 59 with the use of auxiliary mounting plate 53 as seen in FIG. 16 , or to the front of the vehicle such as a skid steer 61 with the universal mount 45 as is seen in FIG. 15 . In either configuration, the controller 57 may be located in the cabin of the dump truck 59 or in the skid steer 61 allowing the operator of either vehicle to operate the functions of the aggregate-spreading device 1 .
When operating the aggregate-spreading device 1 from a remote location with the controller 57 from the interior of the dump truck 59 or from the interior of skid steer 61 , a means for viewing is preferably used that enables the operator to see the aggregate coming out of the dump truck 59 and being supplied to any spreader assembly. The means for viewing may include a simple device such as a plurality of mirrors or a more sophisticated device such as video cameras mounted on the aggregate-spreading device 1 and monitors located inside the cabin of the respective vehicle. Such a configuration allows for a single person to operate the dump truck 59 and operate the aggregate-spreading device 1 when the aggregate-spreading device 1 is attached to the dump truck 59 as shown in FIG. 16 .
FIG. 12 shows a rear side view of the aggregate-spreading device 1 that includes a single spreader assembly 14 . As there is only a single spreader assembly 14 , the conveyor drive unit assembly 35 , bearing 36 , threaded rod 39 , and threaded rod insertion point 42 are exposed on the opposite side of the skeletal frame 10 . The hopper 5 is attached to the skeletal frame 10 by the hopper support bar 12 . FIG. 13 discloses a front side view of the aggregate-spreading device 2 with a single spreader assembly 14 , just as with the dual spreader configuration of FIGS. 1-7 . The single spreader device includes a pair of contact rollers 55 attached to the front plate 33 . The contact rollers 55 are designed to contact the rear wheels of a dump truck 59 , as shown in FIG. 15 , when the device is pushed from the rear with attachment of a skid steer 61 via the auxiliary universal mount 45 . The wheels 60 allow the aggregate-spreading device 1 to roll on the ground as it is pushed by the skid steer 61 or when the device is suspended from the rear end of a dump truck as seen in FIG. 16 via the auxiliary mounting plate 53 . The hopper 5 receives aggregate from a dump truck 59 , as seen in FIGS. 15 and 16 , and is suspended above the conveyor 30 , as seen in FIG. 14 , by a single attachment point, the hopper support bar 12 . The spreader assembly 14 operates as discussed above.
A top side view of the aggregate-spreading device 1 with a single spreader assembly 14 is seen in FIG. 14 . Looking inside the hopper 5 , the side wall 8 , front wall 6 , cutout wall 9 , and rear wall 7 are shown. Aggregate supplied to the hopper 5 is directed to fall directly on the conveyor 30 for delivery to the single spreader assembly 14 as the conveyor is rotated by the conveyor drive unit assembly 35 . The bearing 36 assists the conveyor drive unit assembly 35 in rotation and the threaded rod insertion point 42 secures the threaded rod 39 , seen in FIG. 8 , to the skeletal frame 10 thus allowing the conveyor drive unit assembly 35 to be positionable for adjusting the tension of the conveyor 30 . The universal mount 45 , secured to the skeletal frame 10 and reinforced by the extension 50 , allows attachment of the aggregate-spreading device 1 to a vehicle such as a skid steer 61 , as seen in FIG. 15 . The aggregate-spreading device 1 may alternatively be secured to the rear side of a dump truck 59 with the auxiliary mounting plate 53 , as shown in FIG. 16 .
Although the best mode contemplated by the inventor of carrying out the present invention is disclosed above, practice of the present invention is not limited thereto. It will be manifest that various additions, modifications, and rearrangements of the features of the present invention may be made without deviating from the spirit and scope of the underlying inventive concept. Moreover, the individual components need not be formed in the disclosed shapes, or assembled in the disclosed configuration, but could be provided in virtually any shape and assembled in virtually any configuration. Furthermore, all the disclosed features of each disclosed embodiment can be combined with, or substituted for, the disclosed features of every other disclosed embodiment except where such features are mutually exclusive.
It is intended that the appended claims cover all such additions, modifications, and rearrangements. Expedient embodiments of the present invention are differentiated by the appended claims. | An aggregate-spreading device is disclosed for widening roads, filling trenches, spreading any kind of road construction material, and creating shoulders on the side of roads at a controllable, quick, and steady pace. The aggregate-spreading device may be controlled by electronic motors and electronic actuators. The aggregate-spreading device is equipped with a skeletal frame, either a first and a second adjustable spreader assembly attached on opposing ends of the skeletal frame, or a single spreader assembly for allowing an operator precise control over placement of an aggregate. The aggregate may be supplied to the first or second adjustable spreader assemblies by adjusting the rotation of a reversible conveyor system. The skeletal frame simplifies manufacturing of the aggregate-spreading device and allows for easy repairs and maintenance. The electronic motors and electronic actuators eliminate the need for hydraulics, allowing an operator to control the device from a remote location with a controller. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to a method for preventing or reducing dental caries wherein the carbohydrate erythrose is employed in chewing gum to inhibit growth of Streptococcus mutans ("S. mutans") in the mouth. The present invention also relates to chewing gum formulations containing erythrose.
Foods containing natural sugars such as sucrose and dextrose have long been recognized as a major contributing cause of dental caries. The sugars are easily utilizable sources of nutrition for bacteria, specifically S. mutans found in the mouth. This bacteria is also responsible for the formation of plaque. S. mutans ferments residual sugar, thereby producing acids that dissolve the minerals of the teeth.
In recent years, certain anti-cariogenic substances have been incorporated into chewing gum and other orally-usable products. For example, U.S. Pat. No. 4,390,523, issued Jun. 28, 1983, to Huchette et al., teaches the substitution of sorbose for sucrose as a sweetener in chewing gum in order to reduce the production of fermentation acids in the mouth.
U.S. Pat. Nos. 4,457,921, issued Jul. 3, 1984, and 4,508,713 issued Apr. 2, 1985, both to Stroz et al., teach a method for treating teeth with hydrogenated starch hydrolysate, in conjunction with sucrose, in a chewing gum composition, in order to reduce dental caries.
U.S. Pat. No. 4,374,122, issued Feb. 15, 1983, also to Stroz et al., teaches the use of a compound comprising 3,4-dihydro-6-methyl-1,2,3-oxathiazine-4-one-2,2-dioxide, or the sodium, ammonium, potassium or calcium salts thereof, in an orally-usable carrier, including chewing gum, in order to reduce dental caries.
U.S. Pat. No. 4,518,581, issued May 21, 1985, to Miyake et al., teaches the use of a substance selected from the group consisting of isomaltosyl mono-, di- and tri-glucoses, and reduction products thereof, in orally-usable products including chewing gum in order to reduce dental caries.
U.S. Pat. No. 4,714,612, issued Dec. 22, 1987, to Nakamura et al., teaches the use of γ-globulin in chewing gum to combat Bacteroides gingivalis from colonizing in the mouth.
European Patent Application 0 342 369 A2, filed by Lembke et al. and published November 23, 1989, in the name of Biodyn AG, teaches the use of galactose in numerous orally-usable products, including chewing gum, in order to protect against dental caries.
In U.S. Pat. No. 3,429,716, issued Feb. 25, 1969, to Andrews, erythrose is used to retard the oxidation of food and stabilize anhydrous food products including chewing gum. However, the erythrose concentration is well below the levels mentioned herein, and there is no teaching in the Andrews patent regarding anti-cariogenic properties.
In an effort to reduce dental caries, artificial sweeteners and non-fermentable carbohydrates such as polyols have been used in place of the sugars which are used to give bulk to chewing gum. However, all polyols have the disadvantage of causing gastrointestinal disturbances if consumed in too great a quantity. It would be advantageous to be able to use a carbohydrate or carbohydrate-like compound as a bulking agent in chewing gum that would not contribute to dental caries or cause gastrointestinal disturbances.
SUMMARY OF THE INVENTION
It has been surprisingly found that the carbohydrate erythrose inhibits bacterial growth and may thus be used in chewing gum and confections to reduce the incidence of dental caries. Amounts of erythrose in a chewing gum formula sufficient to inhibit S. mutans may reduce the development of dental caries.
In accordance with one aspect of the present invention, there is provided a chewing gum formulation containing an amount of erythrose effective to give the chewing gum anti-caries properties, preferably at least 2.0% by weight erythrose, and more preferably from about 2.5 to about 40% by weight erythrose. Even more preferably, the weight range of erythrose is from about 3 to about 35%, and still more preferably, from about 5 to about 30%.
The present invention also provides a method of treating teeth to reduce or prevent dental caries by gradually administering erythrose over a period of time. This is accomplished by using a chewing gum formulation containing an amount of erythrose effective to give the gum anti-caries properties.
The method described above preferably utilizes a chewing gum formulation containing at least 2.0% by weight erythrose, more preferably from about 2.5 to about 40% by weight erythrose. Even more preferably, the method utilizes a chewing gum formulation wherein the weight range of erythrose is from about 3 to about 35%, and still more preferably, from about 5 to about 30%.
DETAILED DESCRIPTION
Erythrose is a 4-carbon carbohydrate (aldotetrose), and is one of the simple aldoses. It is a syrupy material and is very soluble in water. It has an empirical formula of C 4 H 8 O 4 , and a molecular weight of 120.10. Its structure is: ##STR1##
Erythrose exists in D and L optical isomers, 15 both of which (and their mixtures) are useful in the present invention. The D- isomer is preferred, since it is readily available commercially as an 85% solution in water.
In vitro tests which are part of the present invention, and which are described in more detail below, indicate that erythrose inhibits growth of S. mutans. An initial test revealed the surprising effectiveness of a 5% solution of erythrose over negative controls of xylose solutions. Later tests showed that erythrose was effective in a 2% solution, and even for a short term, in a 0.5% solution. These tests show erythrose was effective in inhibiting the growth of S. mutans, and is thus bacteriostatic. In some instances the population of S. mutans decreased, indicating that bacteria may be killed by erythrose. This killing action is described as bactericidal.
Chewing gum is used to administer erythrose into the mouth. In general, a chewing gum composition comprises a water soluble bulk portion; a water insoluble, chewable, chewing gum base portion; and, typically, water insoluble flavor ingredients. The water soluble bulk portion, which in the case of the invention includes erythrose, dissolves with a portion of the flavor over a period of time, while the consumer chews the gum. The gum base portion is retained in the mouth throughout the chew.
The insoluble gum base generally includes elastomers, resins, fats, oils, waxes, softeners and inorganic fillers. The elastomers may include polyisobutylene, isobutylene-isoprene copolymer, styrene butadiene rubber and natural latexes such as chicle. The resins may include polyvinyl acetate, ester gums and terpene resins. Low molecular weight polyvinyl acetate is a preferred resin. Fats and oils may include animal fats such as lard and tallow, vegetable oils such as soybean and cottonseed oils, hydrogenated and partially hydrogenated vegetable oils, and cocoa butter. Commonly used waxes include petroleum waxes such as paraffin and microcrystalline wax, natural waxes such as beeswax, candelilla, carnauba and polyethylene wax. The present invention contemplates the use of any commercially acceptable chewing gum base.
The gum base typically also includes a filler component such as calcium carbonate, magnesium carbonate, talc, dicalcium phosphate and the like; softeners, including glycerol monostearate and glycerol triacetate; and optional ingredients such as antioxidants, colors and emulsifiers. The gum base constitutes from about 5 to about 95% by weight of the chewing gum, more typically from about 10 to about 50% by weight of the chewing gum, and most commonly from about 20 to about 35% by weight of the chewing gum.
The water soluble portion of the chewing gum may include softeners, bulk sweeteners, high intensity sweeteners, flavoring agents and combinations thereof. Softeners such as glycerin are added to the chewing gum in order to optimize the chewability and mouth feel of the gum. The softeners, which are also known as plasticizers or plasticizing agents, constitute from about 0.1 to about 15% by weight of the chewing gum.
Aqueous sweetener solutions such as those containing sorbitol, hydrogenated starch hydrolysates, syrups of xylitol, maltitol, hydrogenated isomaltulose and other polyols, corn syrup and combinations thereof, may also be used as softeners and binding agents in the chewing gum.
Bulk sweeteners constitute from about 5 to about 90% by weight of the chewing gum, more typically from about 20 to about 80% by weight of the chewing gum and most commonly from about 30 to about 60% by weight of the chewing gum.
Sweeteners contemplated by the present invention for use in chewing gum include both sugar and sugarless components. Sugar sweeteners generally include saccharide-containing components commonly known in the chewing gum art. These sugar sweeteners include but are not limited to sucrose, dextrose, maltose, dextrin, dried invert sugar, fructose, levulose, galactose, corn syrup solids and the like, alone or in any combination.
Any combination of sugar and/or sugarless sweeteners may be employed in the chewing gum. Further, a sweetener may be present in a chewing gum in whole or in part as a water soluble bulking agent. It is a portion of the usual sweetener/bulking agent which is replaced with erythrose, in the quantities described above. In addition, the softener may be combined with a sweetener such as an aqueous sweetener solution.
Bulk sweeteners preferably include sugarless sweeteners and components. Sugarless sweeteners include components with sweetening characteristics but are devoid of the commonly known sugars. Sugarless sweeteners include but are not limited to sugar alcohols such as sorbitol, mannitol, xylitol, hydrogenated starch hydrolysates, maltitol, hydrogenated isomaltulose, and the like, alone or in combination.
High intensity sweeteners may also be present and are commonly used with sugarless sweeteners. When used, high intensity sweeteners typically constitute from about 0.001 to about 5% by weight of the chewing gum, preferably from about 0.01 to about 1% by weight of the chewing gum. Typically, high intensity sweeteners are at least 20 times sweeter than sucrose. These may include but are not limited to sucralose, aspartame, salts of acesulfame, alitame, saccharin and its salts, cyclamic acid and its salts, glycyrrhizin, dihydrochalcones, thaumatin, monellin, and the like, alone or in combination.
The flavoring agent should generally be present in the chewing gum in an amount within the range of from about 0.1 to about 15% by weight of the chewing gum, preferably from about 0.2 to about 5% by weight of the chewing gum, most preferably from about 0.5 to about 3% by weight of the chewing gum. Flavoring agents may include essential oils, synthetic flavors or mixtures thereof including but not limited to oils derived from plants and fruits such as citrus oils, fruit essences, peppermint oil, spearmint oil, other mint oils, clove oil, oil of wintergreen, anise and the like. Artificial flavoring agents and components may also be used in the chewing gum. Natural and artificial flavoring agents may be combined in any sensorially acceptable fashion.
Optional ingredients such as colors, emulsifiers, pharmaceutical agents and additional flavoring agents may also be included in chewing gum.
In general, chewing gum is manufactured by sequentially adding the various chewing gum ingredients to any commercially available mixer known in the art. After the ingredients have been thoroughly mixed, the gum mass is discharged from the mixer and shaped into the desired forms such as by rolling into sheets and cutting into sticks, extruding into chunks, or casting into pellets. Generally, the ingredients are mixed by first melting the gum base and adding it to the running mixer. The base may also be melted in the mixer itself. Color may also be added at this time. A softener such as glycerin may then be added next along with syrup and a portion of bulking agent, which may include erythrose. Further portions of the bulking agents, including any remaining erythrose, may then be added to the mixer.
The present invention contemplates the blending of erythrose into the chewing gum, thus allowing its gradual release into the mouth as the gum is chewed. Erythrose may be mixed with the chewing gum ingredients at any time during the manufacturing process, but preferably it is mixed in with the bulking agent. Although in a lesser quantity, erythrose may also be coated on the outside of the gum.
The following examples are not to be construed as limitations upon the present invention, but are included merely as an illustration of various embodiments.
EXAMPLES
Example 1: Testing 5% Erythrose
This example demonstrates that erythrose effectively inhibits or kills S. mutans.
Five gram samples of D-erythrose (85% solution in water from Aldrich Chemical Co., Milwaukee, Wis.), D,L-glyceraldehyde (Aldrich, 98% purity), xylose (Aldrich) and xylose (Roquette) were obtained. Five percent test solutions of each were prepared from 10% stock solutions (1 gram of sample per 10 grams of solution) by diluting 1:1 (1 gram of 10% solution per 1 gram of diluent) with sterile distilled water for the Paper Disc assay and Trypticase Soy Broth ("TSB") for the broth assay.
An S. mutans culture (ATCC 25175) was prepared with TSB and incubated 24 hours at 35° C. Paper Disc Inhibition tests were performed, wherein spread plates were prepared by inoculating each Typtone Glucose Yeast Extract agar plate (TGY) with 0.1 ml of a 1:1000 dilution of the 24-hour S. mutans culture. The plate was then allowed to dry for 30 minutes. For each test solution, two 12.5 mm sterile discs were saturated with 50 microliters of solution and each was placed in the center of an inoculated TGY plate. Two additional discs were saturated with sterile distilled water to serve as negative controls. These plates were incubated for 24 hours at 35° C. After incubation, the plates were observed for clearing zones around the discs, and the diameter of the zone was measured.
After 24 hours of incubation, there was no visible zone of inhibition around the discs with 5.0% erythrose. (See Table 1.) However, strong positive evidence of the inhibiting effect of erythrose on S. mutans is illustrated below in the tests conducted in TBS.
TABLE 1______________________________________Results of Disc Inhibition Tests of FourCarbohydrates on S. mutansSample Plate Zone Diameter (mm)*______________________________________Erythrose 1 <12.5Erythrose 2 <12.5Glyceraldehyde 1 39Glyceraldehyde 2 36Xylose (Aldrich) 1 <12.5Xylose (Aldrich) 2 <12.5Xylose (Roquette) 1 <12.5Xylose (Roquette) 2 <12.5______________________________________ *Each result is the average of 3 measurements.
Inhibition in TSB was also tested. An overnight culture of S. mutans was diluted 1:1000. Then 0.1 ml of this culture was added to tubes containing 5.0% of glyceraldehyde, erythrose or xylose in TSB. The tubes were incubated in a 35° C water bath. After 0, 4, 8, 24, and 48 hours in the water bath, serial dilutions of the tube solutions were plated. A tube prepared without carbohydrates was also used as a control. The results are expressed in Table 2 as the number of viable colony forming units per milliliter of solution (cfu/ml).
Initial plate counts for S. mutans ranged from 23,000 cfu/ml to 60,000 cfu/ml (Table 2). After 4 hours of incubation at 35° C., counts decreased to <10 cfu/ml in the erythrose solution, and remained under 10 cfu/ml through the 48-hour plating. After 8 hours of incubation at 35° C., counts increased between 5 and 12fold for the no-carbohydrate control and xylose. After 24 hours of incubation, counts increased between 2,300 and 10,000-fold, and remained relatively constant through the 48 hour plating.
These data indicate that growth rates in the tubes containing xylose did not vary significantly from growth rates in tubes containing straight TSB. In contrast, in tubes containing erythrose, S. mutans died. These results support the conclusions that xylose has no inhibitory effect on S. mutans, but that erythrose effectively inhibits or kills S. mutans.
TABLE 2______________________________________Results of Inhibition Tests of FourCarbohydrates on S. mutansTime (hours) Aerobic Plate Count (cfu/ml)______________________________________Control 0 60,000 4 69,000 8 120,00024 1,200,000,00048 1,100,000,000Erythrose 0 36,000 4 <10 8 <1024 <1048 <10Glyceraldehyde 0 23,000 4 <10 8 <1024 <1048 <10Xylose (Aldrich) 0 39,000 4 110,000 8 200,00024 460,000,00048 570,000,000Xylose (Roquette) 0 26,000 4 123,000 8 290,00024 680,000,00048 400,000,000______________________________________
Example 2: Testing 0.1%, 0.5%, and 2.0% Erythrose
This example demonstrates the dose-efficacy relationship between the concentration of inhibitory carbohydrate and bacterial multiplication. Using the same methodology as above, 5 grams of D-erythrose and 10 grams of D,L-glyceraldehyde were dissolved and diluted to obtain four concentrations ranging between 0.10% and 2.0%. This was done by preparing 10% stock solutions and diluting them according to the following schedule:
2.0 grams of 10% solution was diluted with 8.0 grams of diluent to yield 2.0% solution.
1.0 gram of 10% solution was diluted with 9.0 grams of diluent to yield 1.0% solution.
2.0 grams of 2% solution was diluted with 6.0 grams of diluent to yield 0.5% solution.
1.0 gram of 1% solution was diluted with 9.0 grams of diluent to yield 0.1% solution.
Water was the diluent for the disc assay and TSB was the diluent for the broth assay. Two strains of S. mutans (ATCC 25175 and ATCC 27351) were prepared in TSB incubated 24 hours at 35° C. before inhibition testing.
In the Disc Inhibition test, after 24 hours, incubation there was, as with 5.0% erythrose solutions in Example 1, no zone of inhibition visible on plates containing discs with 2.0% erythrose (Table 3). Again, as in Example 1, the results in TSB also showed inhibition. Initial plate counts in the control and erythrose plates for ATCC 25175 ranged from 3,500 cfu/ml (0.10% erythrose, Table 4) to 4,400 cfu/ml (control, Table 5); and for ATCC 27351, from 1,400 cfu/ml (0.10% erythrose) to 2,100 cfu/ml (2.00% erythrose). After 4 hours of incubation at 35° C., counts decreased to <10 cfu/ml for both cultures in
TABLE 3______________________________________Results of Disc Inhibition Tests on S. mutans Zone Zone Diameter Diameter (mm)* (mm)*Sample Plate (ATCC 25175) (ATCC 27351)______________________________________2.0% Erythrose 1 <12.5 <12.5 2 <12.5 <12.50.5% Erythrose 1 <12.5 <12.5 2 <12.5 <12.50.1% Erythrose 1 <12.5 <12.5 2 <12.5 <12.52.0% Glyceraldehyde 1 22 17 2 18 220.5% Glyceraldehyde 1 12.5 <12.5 2 <12.5 <12.50.1% Glyceraldehyde 1 <12.5 <12.5 2 <12.5 <12.5______________________________________ *Each result is the average of 3 measurements.
2.0% erythrose solution, and remained below 10 cfu/ml through the 48 hour plating. The three tubes containing TSB broth with 0.5% erythrose exhibited inhibition between the 8 and 24 hour platings, but showed increased growth by the 48 hour plating.
These data indicate that tubes containing 0.5% erythrose showed some short term inhibition in TSB. The effect was temporarily bacteriostatic as there was little change in the viable count. In tubes containing 2.0% erythrose, S. mutans died. This level of erythrose was bactericidal in broth, but only the 2.0% glyceraldehyde was bactericidal by disc assay.
TABLE 4______________________________________Results of Broth Inhibition Test forErythrose on S. mutans % ErythroseTime (Hours) 0.10 0.50 2.00______________________________________ATCC 25175 0 3,500 4,100 3,800 4 6,100 5,500 <10 8 5,100 2,300 <1024 210,000,000 50 <1048 48,000,000 45,000 <10ATCC 27351 0 1,400 2,000 2,100 4 1,300 2,300 <10 8 3,800 1,800 <1024 210,000,000 20 <1048 48,000,000 730 <10______________________________________
TABLE 5______________________________________Results of Broth Inhibition Test forGlyceraldehyde on S. mutans % Glyceraldehyde 0.00Time (Hours) (Control) 0.10 0.50 2.00______________________________________ATCC 25175 0 4,400 3,700 3,400 3,300 4 8,100 2,800 <10 <10 8 25,000 900 <10 <1024 6,800,000,000 1,200 <10 <1048 270,000,000 170,000 <10 <10ATCC 27351 0 1,900 2,100 2,400 1,900 4 3,600 1,600 <10 <10 8 6,800 630 <10 <1024 5,300,000,000 50 <10 <1048 100,000 270 <10 <10______________________________________
The environment of the mouth, as erythrose is gradually released from the chewing gum into the saliva, is expected to simulate the environment in the TSB test, and thus inhibit S. mutans.
Example 3: Preparation of a Sugar-Free Chewing Gum
A spearmint flavored sugar-free chewing gum can be made with the following ingredients:
______________________________________ %______________________________________ Gum base 25.0 Mannitol 8.0 Sorbitol 41.4 Softener 0.2 Glycerin 8.0 Flavor 1.4 Erythrose 16.0 100.0%______________________________________
The chewing gum can be prepared by softening the gum base at about 65° C. (150° F.) and adding it to the mixer with the sorbitol. After 2 minutes of mixing, mannitol is added, after which erythrose is added, followed by glycerin. These ingredients are mixed a total of 6 minutes, then flavor is added and mixed another 5 minutes. The gum is discharged, rolled thin, and cut into sticks. The chewing gum product will have a pleasant taste and inhibit growth of S. mutans in the mouth.
Example 4: Preparation of a Sugared Chewing Gum
A peppermint flavored gum can be prepared using the following ingredients:
______________________________________ %______________________________________Gum base 20.045 Baume corn syrup 17.0Powdered sugar 30.0Dextrose 10.0Peppermint flavor 1.0Erythrose 20.0Glycerin 2.0 100.0%______________________________________
The chewing gum can be prepared as described for Example 3. The chewing gum product will have a pleasant taste and inhibit growth of S. mutans in the mouth.
Those skilled in the art will recognize that variations of the above described procedure may be followed. It is to be understood that an equivalent of changes and modifications of the embodiments described above are also contemplated by the present invention. For example, it will be apparent to those skilled in the art, in light of the present disclosure, that equivalents of erythrose, such as various erythrose isomers as erythrulose and threose, or erythrose derivatives like salts of erythrose-4-phosphate and erythrose-4-phosphate diethyl acetal, may be substituted in whole or in part for erythrose itself, within the spirit of the invention. | A chewing gum formulation to fight cavities comprises sufficient erythrose to give the chewing gum anti-caries properties. Also disclosed is a method of reducing or preventing dental caries by inhibiting the growth of Streptococcus mutans in the presence of fermentable carbohydrates in the mouth. This method comprises contacting the teeth with chewing gum containing erythrose, wherein the erythrose is present in sufficient quantity to give the chewing gum anti-caries properties. | 8 |
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
The present invention relates to a deterioration diagnosis method and device which permits diagnosis of deterioration degree of such as of mineral oil series insulation oil, insulation medium such as liquid per-fluorocarbon and cellulose series insulation material used for an oil filled electrical machine and apparatus, a resin material for a resin mold insulation type electrical machine and apparatus and an insulation material for a gas such as SF 6 gas insulation type electrical machine and apparatus without destruction thereof used in an electrical machine and apparatus during the operation thereof without stopping the operation.
2. Conventional Art
JP-A-7-272939 (1995) discloses a diagnosis method of estimating such as deterioration degree and life time of such as insulation oil and insulation paper used in an oil filled electrical machine and apparatus in which such as frufural, carbon monoxide and carbon dioxide which are decomposition products of the insulation paper are extracted from the insulation oil, gas analysis is performed thereon and deterioration degree of the insulation paper is estimated based on a correlation diagram between gas generation amount and polymerization remaining rate of the insulation paper which was determined in advance.
In the above prior method, since the amount of gas generated in association with deterioration is extremely small, a special measure for extracting the generated gas was necessitated as well as a large size evaluation device for gas analysis was required which make the above diagnosis method inconvenience.
Further, although the life time of such apparatus is controlled by the deterioration degree of the insulation paper, in the above method the deterioration degree of the insulation paper is not directly diagnosed, but the diagnosis is performed indirectly on the decomposition products of the insulation paper dissolved in the insulation oil. Therefore, if, for example, the insulation oil such as for a medium size transformer and a small size transformer is exchanged, an accurate measurement value of total decomposition products can not already been obtained which was one of problems.
SUMMARY OF THE INVENTION
An object of the present invention is to resolve the above problems and to provide a deterioration diagnosis method and device which permits diagnosis of deterioration degree of such as of mineral oil series insulation oil, insulation medium such as liquid per-fluorocarbon and cellulose series insulation material used for an oil filled electrical machine and apparatus, a resin material for a resin mold insulation type electrical machine and apparatus and an insulation material for a gas such as SF 6 gas insulation type electrical machine and apparatus without destruction thereof used in an electrical machine and apparatus during the operation thereof without stopping the operation.
The present inventors investigated relationships between deterioration degree of such as insulation oil and insulation paper used in oil filled electrical apparatuses and optical properties thereof and invented a diagnosis method and a diagnosis device through which the deterioration degree can be judged based on variation of transmission light intensity of the insulation oil and variation of reflection light intensity of the insulation paper due to thermal deterioration thereof. Namely, as illustrated in FIG. 4 an average polymerization remaining rate and reflection absorbance difference of the insulation paper have showed a good correlation. The principle of the present invention is as follows.
(1) A deterioration diagnosis method and device of an electrical machine and apparatus of the present invention in which irradiation light from a light source of at least two kinds of homogeneous light sources having different wavelengths each other is introduced inside the electrical machine and apparatus via an irradiation use optical fiber, emitting light from the irradiation use optical fiber is transmitted through insulation medium having transmission distance a, thereafter, enters into a light receiving use optical fiber which is guided to the outside of the electrical machine and apparatus and is transferred and introduced into a light quantity measurement unit, is characterized in that, the deterioration diagnosis method and device comprises the steps of: adjusting the intensities of the light source of homogeneous lights so that all of the intensities thereof at the light quantity measurement unit shows a constant value; thereafter introducing irradiating light from the light source of homogeneous light into the inside of the electrical machine and apparatus via the irradiation use optical fiber; irradiating a surface of an insulation material located at a position having transmission distance of a/2; guiding reflecting light from the surface of the insulation material to the light quantity measurement unit by making use of the light receiving use optical fiber which guides the reflection light from the surface of the insulation material to the outside of the electrical machine and apparatus; calculating in a deterioration degree processing unit reflection absorbances (Aλ) for the respective wavelengths according to equation (1) based on the output value from the light quantity measurement unit; processing either reflection absorbance difference (ΔAλ) between those of any two wavelengths according to equation (2) or reflection absorbance ratio (Aλ') between those of any two wavelengths according to equation (3); and further processing by comparison a relationship between deterioration degree of the insulation material to be measured which is stored in advance in a form of master curve and either the processed reflection absorbance difference or the processed reflection absorbance ratio to thereby judge the deterioration degree of the insulation material,
Aλ=-log (Rλ/100) (1)
ΔAλ=Aλ1-Aλ2 (wherein λ1<λ2)(2)
Aλ'=Aλ1/Aλ2 (wherein λ1<λ2)(3)
wherein reflectance of the insulation material to be measured at wavelength λ(nm) is assumed as Rλ(%).
For the light source of homogeneous light a semiconductor laser (LD) and a light emitting diode (LED) having a peak wavelength of 650˜1310 nm are preferable, because they are easily available, and show a long life time and a stable performance. In particular, the LD and LED light source having a peak wavelength such as 655, 660, 670, 780, 820, 830, 850, 1300 and 1310 nm is preferable. With a light source having a wavelength other than the above range, the detection range of a detector (a light quantity measurement unit) is exceeded even when the deterioration of an object to be measured is comparatively small which may cause the light measurement impossible. When the original color of the object to be measured is pale, it is further preferable to use a light source having a peak wavelength less than 800 nm such as 655, 660, 670, 780 and 800 nm. On the other hand, when the object to be measured is originally colored, it is further preferable to use a light source having a peak wavelength near infrared range such as 780, 800, 820, 830, 850, 1300 and 1310 nm.
(2) A deterioration diagnosis method and device of an electrical machine and apparatus in which irradiation light from a halogen lamp irradiorating continuous white color light is introduced via a spectroscope inside the electrical machine and apparatus with an irradiation use optical fiber, emitting light from the irradiation use optical fiber is transmitted through insulation medium having transmission distance a, thereafter, enters into a light receiving use optical fiber which is guided to the outside of the electrical machine and apparatus and is transferred and introduced into a light quantity measurement unit, characterized in that the deterioration diagnosis method and device comprising the steps of: measuring wavelength dependency of the irradioration light intensity; thereafter introducing irradiating light from the halogen lamp into the inside of the electrical machine and apparatus via the irradiation use optical fiber; irradiating a surface of an insulation material located at a position having transmission distance of a/2; guiding reflecting light from the surface of the insulation material to the light quantity measurement unit by making use of the light receiving use optical fiber which guides the reflection light from the surface of the insulation material to the outside of the electrical machine and apparatus; calculating in a deterioration degree processing unit reflection absorbances (Aλ) for the respective wavelengths according to equation (1) based on the output value from the light quantity measurement unit; processing either reflection absorbance difference (ΔAλ) between those of any two wavelengths according to equation (2) or reflection absorbance ratio (Aλ') between those of any two wavelengths according to equation (3); and further processing by comparison a relationship between deterioration degree of the insulation material to be measured which is stored in advance in a form of master curve and either the processed reflection absorbance difference or the processed reflection absorbance ratio to thereby judge the deterioration degree of the insulation material,
Aλ=-log (Rλ/100) (1)
ΔAλ=Aλ1-Aλ2 (wherein λ1<λ2)(2)
Aλ'=Aλ1/Aλ2 (wherein λ1<λ2)(3)
wherein reflectance of the insulation material to be measured at wavelength λ(nm) is assumed as Rλ(%).
Variation of reflection absorbance spectrum in association with thermal deterioration of organic materials such as insulation paper and mold resin is generally represented by the curves shown in FIG. 3.
As illustrated in FIG. 3, the reflection absorbance extremely increases at the side of short wavelengths of a visible range in association with deterioration thereof, therefore, if a light source having a peak wavelength less than 650 nm is used, because of limitation of measurement range of the detector (light quantity measurement unit) it is substantially difficult to continue measurement of reflection absorbance of a material used until the life time point of the machine and apparatus concerned. The extreme increase of the reflection absorbance at the side of short wavelengths is primarily caused by the increases of electron transition absorption loss due to deterioration reaction by thermal oxidation of the material.
Further, in association with the increase of the deterioration degree, the reflection absorbance Aλ increases more at the side of short wavelengths, therefore, reflection absorbance difference ΔAλ(=Aλ1-Aλ2) between those of any two wavelengths or reflection absorbance ratio A'λ(=Aλ1/Aλ2) between those of any two wavelengths also increases, wherein λ1<λ2. For example, when assuming the reflection absorbance difference ΔAλ between those of wavelength λ1 (nm) and wavelength λ2 (nm) as and α1, α2 and α3 in the order according to materials having larger deterioration degree, the relationship α1>α2>α3 stands. The same is true with respect to the reflection absorbance ratio Aλ'.
These variations in such as reflection absorbance difference and reflection absorbance ratio in association with the thermal deterioration are correlated with variations of a variety of material properties of materials and through measurement of these reflection absorbance parameters the decrease of material properties of the materials can be non-destructively diagnosed. For example, a relationship between average polymerization remaining degree and reflection absorbance difference of an insulation paper in an oil filled transformer shows a good correlation as illustrated in FIG. 4.
The deterioration degree is generally represented by reduced time θ as disclosed in JP-A-3-226651(1991). When the deterioration degree is expressed by reduced time θ, and if materials having variety of thermal histories show same reduced time θ, their deterioration degree is implied as same. The reduced time θ(h) is defined by the following equation (4). ##EQU1##
Wherein, ΔE is an apparent activation energy for thermal deterioration (J/mol), R is gas constant (J/K/mol), T is absolute temperature for thermal deterioration and t is deterioration time (h). ΔE of such as resins and oils can be easily calculated by plotting variation of reflection absorbance difference or reflection absorbance ratio for the deterioration temperature of a few kinds thereof according to Arrhenius's law.
When assuming the reduced time θ 0 is at the life time point of an apparatus using an insulation oil and an insulation paper which is determined beforehand, the difference Δθ(=θ 0 -θ) with reduced time θ determined based on actual measurement is a reduced time representing the remaining life time which can be used as a measure for judging the deterioration degree. Namely, the remaining life time Δθ(h) is expressed by the following equation (5). ##EQU2##
When the use temperature condition of the apparatus after time t is set, the remaining life time Δt(=t 0 -t) can be determined according to equation (5).
When diagnosing the deterioration degree of an insulation paper used in an oil filled electrical apparatus based on reflection absorbance difference (ΔAλ) or reflection absorbance ratio (Aλ'), there are no problems when the deterioration degree is low, however, when the insulation oil is colored depending on deterioration advancement, an accurate reflection absorbance can not be obtained due to absorbance by the colored insulation oil. FIG. 6 shows an example of master curves of light transmission loss difference of an insulation oil between wavelength of 660 nm and 850 nm and illustrates a tendency that when the deterioration advances the light transmission loss increases exponentially.
In order to correct absorption increase of the insulation oil in association with the deterioration thereof, in the present invention intensities of transmission light of respective wavelengths through distance a in the insulation oil is measured and correction of intensity between respective wavelengths is performed accordingly. When the intensity of reflection light of the insulation paper is measured at the distance of 1/2 of the transmission light path length, namely a/2, the absorption in the insulation oil through the back and fourth travel thereof is canceled out and an accurate reflection absorption value of the insulation paper is obtained.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram showing an application manner of a deterioration diagnosis device for an oil filled electrical apparatus (transformer) according to the present invention
FIG. 2 is a schematic cross sectional view of a probe used in the device shown in FIG. 1;
FIG. 3 is a conceptual diagram showing variation of reflection absorbance spectrum of a material;
FIG. 4 is an example of diagrams showing a relationship between average polymerization remaining rate and reflection absorbance difference of an insulation paper;
FIG. 5 is an example of reflection absorbance difference master curves serving as a reference for judging deterioration degree used in the present invention;
FIG. 6 is an example of light transmission loss difference master curves of an insulation oil;
FIG. 7 is a flowchart for deterioration degree judgement processing;
FIG. 8 is a schematic diagram showing an application manner of a deterioration diagnosis device for a liquid per-fluorocarbon filled transformer according to the present invention;
FIG. 9 is an example of reflection absorbance ratio master curves serving as a reference for judging deterioration degree in the present invention;
FIG. 10 is a schematic diagram showing an application manner of a deterioration diagnosis device for a SF 6 gas filled transformer according to the present invention; and
FIG. 11 is a schematic diagram showing an application manner of a deterioration diagnosis device for a resin mold dry type transformer according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Hereinbelow, the present invention is explained in details with reference to embodiments.
(Embodiment 1)
FIG. 1 is a schematic diagram showing an application manner of a deterioration diagnosis device for an oil filled electrical apparatus (transformer). Further, FIG. 7 shows a flowchart of processing for judging deterioration degree.
In FIG. 1, a deterioration degree processing unit 10 uses a note book type personal computer having a built-in hard disk unit. At first respective transmission light quantities of respective wavelengths through an insulation oil are measured and correction is made so that the respective transmission light intensities take a constant value. In the present embodiment, a device which makes use of two wavelengths is explained. A homogeneous light having a peak wavelength λ1=660 nm which is generated from a light source unit 8 incorporating two kinds of LED light sources is introduced to an irradiation use optical fiber 6, reaches into a probe 5 as shown in FIG. 2, passes a half mirror 11 and thereafter is transmitted through the insulation oil having distance a.
The transmitted light is transferred via a light receiving unit 13 and a light receiving use optical fiber 7 to a light quantity measurement unit 9. An optical power meter having a built-in photo diode is used for the light quantity measurement unit 9. The same operation is performed by making use of another homogeneous light having a peak wavelength λ2=850 nm generated from the light source unit 8 and then a light intensity adjustment dial of the light source unit 8 is adjusted so that the transmitting light intensities for the wavelengths λ1 and λ2 are equated. In the present measurement the base value thereof is adjusted at 600 nW. With this operation, an influence of light absorption in association with deterioration of the insulation oil for the deterioration diagnosis of the insulation paper is corrected. Subsequently, quantity of reflection light from the insulation paper, which substantially controls the life time of an oil filled apparatus concerned, is measured. The homogeneous light having a peak wavelength λ1=660 nm from the light source unit 8 is introduced into the irradiation use optical fiber 6 through the like operation, passes the probe 5 and is irradiated onto a surface of an insulation paper on a coil 2. A reflection light measurement unit in the probe 5 includes a shielding ring structure for interrupting stray light from the outside as illustrated in FIG. 2. Further, as shown in FIG. 2, the distance between the probe 5 and the surface of the insulation paper is designed to be 1/2 of the light path length used for measuring the transmission light intensity. The reflection light from the surface of the insulation paper on the coil 2 is transferred via the light receiving use optical fiber 7 to the light quantity measurement unit 9 in which reflection light quantity I 1 ' is measured and the measurement result I 1 ' is output to the deterioration degree processing unit 10. In the deterioration degree processing unit 10, reflectance R660(=100×I 1'/I 0 , I 0 =600) of the homogeneous light having peak wavelength 660 nm is calculated and is stored in a memory. Like operation is performed by making use of the homogeneous light having peak wavelength λ2=850 nm and in the deterioration degree processing unit 10, reflectance R850(=100×I 2 '/I 0 , I 0 =600) of the homogeneous light having peak wavelength 850 nm is calculated and is stored in the memory. With the thus obtained reflectances of the homogeneous lights having peak wavelengths 660 and 850 nm, reflection absorbance difference ΔAλ(=Aλ1-Aλ2) between those of the two wavelengths or reflection absorbance ratio Aλ' (=Aλ1/Aλ2) between those of the two wavelengths is determined. In the hard disk unit of the personal computer, reflection absorbance difference or reflection absorption ratio with respect to deterioration degree as shown in FIG. 5 and FIG. 9 is stored before hand in a form of master curves which are output to the deterioration degree processing unit 10 in which processing for comparison is performed on the stored function values and the reflection absorbance difference or the reflection absorbance ratio determined based on the actual measurement, and the deterioration degree is judged and then is output as the measurement result such as to an external printer (not shown).
In the present embodiment the deterioration degree measurement device of materials which makes use of two homogeneous lights having different peak wavelengths is explained, however the deterioration degree measurement device can be likely operated by making use of three homonegeous lights having different peak wavelengths and three wavelengths use master curves.
Further, the combined lights can be simultaneously irradiated in stead of the time sharing light irradiation. In this instance, it is effective if filtering is performed at the side of detector (a light quantity measurement unit). The device according to the present embodiment can be used both an on-line continuous monitering device and as a portable device performing periodic inspection of an insulation of an electric machine and apparatus.
(Embodiment 2)
Like the embodiment 1, an embodiment 2 of a deterioration diagnosis method and device according to the present invention is applied to a transformer using liquid per-fluorocarbon 14 as insulation medium thereof as shown in FIG. 8.
At first respective transmission light quantities of respective wavelengths through the liquid per-fluorocarbon 14 are measured and correction is made so that the respective transmission light intensities take a constant value. A homogeneous light having a peak wavelength λ1=780 nm which is generated from a light source unit 8 incorporating two kinds of LED light sources is introduced to an irradiation use optical fiber 6, reaches into a probe 5 as shown in FIG. 2, passes a half mirror 11 and thereafter is transmitted through the liquid per-fluorocarbon having distance a.
The transmitted light is transferred via a light receiving unit 13 and a light receiving use optical fiber 7 to a light quantity measurement unit 9. The same operation is performed by making use of another homogeneous light having a peak wavelength λ2=1310 nm generated from the light source unit 8 and then a light intensity adjustment dial of the light source unit 8 is adjusted so that the transmitting light intensities for the wavelengths λ1 and λ2 are equated. In the present measurement the base value thereof is adjusted at 1.0 μW. Subsequently, quantity of reflection light from an insulation paper is measured. The homogeneous light having a peak wavelength λ1=780 nm from the light source unit 8 is introduced into the irradiation use optical fiber 6 through the like operation, passes the probe 5 and is irradiated onto a surface of the insulation paper on a coil 2. The reflection light from the surface of the insulation paper on the coil 2 is transferred via the light receiving use optical fiber 7 to the light quantity measurement unit 9 in which reflection light quantity I 1 ' is measured and the measurement result I 1 ' is output to the deterioration degree processing unit 10. In the deterioration degree processing unit 10, reflectance R780(=100×I 1 '/I 0 , I 0 =1.0) of the homogeneous light having peak wavelength 780 nm is calculated and is stored in a memory. Like operation is performed by making use of the homogeneous light having peak wavelength λ2=1310 nm and in the deterioration degree processing unit 10, reflectance R1310(=100×I 2 '/I 0 , I 0 =1.0) of the homogeneous light having peak wavelength 1310 nm is calculated and is stored in the memory. With the thus obtained reflectances of the homogeneous lights having peak wavelengths 780 and 1310 nm, reflection absorbance difference ΔAλ(=Aλ1-Aλ2) between those of the two wavelengths or reflection absorbance ratio Aλ' (=Aλ1/Aλ2) between those of the two wavelengths is determined. In the hard disk unit of the personal computer, reflection absorbance difference or reflection absorption ratio with respect to deterioration degree as shown in FIG. 5 and FIG. 9 is stored before hand in a form of master curves which are output to the deterioration degree processing unit 10 in which processing for comparison is performed on the stored function values and the reflection absorbance difference or the reflection absorbance ratio determined based on the actual measurement, and the deterioration degree thereof is judged.
(Embodiment 3)
Like the embodiments 1 and 2, an embodiment 3 of a deterioration diagnosis method and device according to the present invention is applied to a transformer using SF 6 gas 15 as insulation medium thereof as shown in FIG. 10.
At first respective transmission light quantities of respective wavelengths through the SF 6 gas are measured and correction is made so that the respective transmission light intensities take a constant value. A homogeneous light having a peak wavelength λ1=780 nm which is generated from a light source unit 8 incorporating two kinds of LED light sources is introduced to an irradiation use optical fiber 6, reaches into a probe 5 as shown in FIG. 2, passes a half mirror 11 and thereafter is transmitted through the SF 6 gas having distance a.
The transmitted light is transferred via a light receiving unit 13 and a light receiving use optical fiber 7 to a light quantity measurement unit 9. The same operation is performed by making use of another homogeneous light having a peak wavelength λ2=1310 nm generated from the light source unit 8 and then a light intensity adjustment dial of the light source unit 8 is adjusted so that the transmitting light intensities for the wavelengths λ1 and λ2 are equated. In the present measurement the base value thereof is adjusted at 1.5 μW. Subsequently, quantity of reflection light from an insulation paper is measured. The homogeneous light having a peak wavelength μ1=780 nm from the light source unit 8 is introduced into the irradiation use optical fiber 6 through the like operation, passes the probe 5 and is irradiated onto a surface of the insulation paper on a coil 2. The reflection light from the surface of the insulation paper on the coil 2 is transferred via the light receiving use optical fiber 7 to the light quantity measurement unit 9 in which reflection light quantity I 1 ' is measured and the measurement result I 1 ' is output to the deterioration degree processing unit 10. In the deterioration degree processing unit 10, reflectance R780(=100×I 1 '/I 0 , I 0 =1.5) of the homogeneous light having peak wavelength 780 nm is calculated and is stored in a memory. Like operation is performed by making use of the homogeneous light having peak wavelength λ2=1310 nm and in the deterioration degree processing unit 10, reflectance R1310(=100×I 2 '/I 0 , I 0 =1.5) of the homogeneous light having peak wavelength 1310 nm is calculated and is stored in the memory. With the thus obtained reflectances of the homogeneous lights having peak wavelengths 780 and 1310 nm, reflection absorbance difference ΔAλ(=Aλ1-Aλ2) between those of the two wavelengths or reflection absorbance ratio Aλ' (=Aλ1/Aλ2) between those of the two wavelengths is determined. In the hard disk unit of the personal computer, reflection absorbance difference or reflection absorption ratio with respect to deterioration degree as shown in FIG. 5 and FIG. 9 is stored before hand in a form of master curves which are output to the deterioration degree processing unit 10 in which processing for comparison is performed on the stored function values and the reflection absorbance difference or the reflection absorbance ratio determined based on the actual measurement, and the deterioration degree thereof is judged.
(Embodiment 4)
Like the embodiments 1 through 3, an embodiment 4 of a deterioration diagnosis method and device according to the present invention is applied to a resin mold dry type transformer as shown in FIG. 11.
At first respective transmission light quantities of respective wavelengths through air serving as insulation dedium in this instance are measured and correction is made so that the respective transmission light intensities take a constant value. A homogeneous light having a peak wavelength λ1=660 nm which is generated from a light source unit 8 incorporating two kinds of LED light sources is introduced to an irradiation use optical fiber 6, reaches into a probe 5 as shown in FIG. 2, passes a half mirror 11 and thereafter is transmitted through the air gap having distance a.
The transmitted light is transferred via a light receiving unit 13 and a light receiving use optical fiber 7 to a light quantity measurement unit 9. The same operation is performed by making use of another homogeneous light having a peak wavelength λ2=850 nm generated from the light source unit 8 and then a light intensity adjustment dial of the light source unit 8 is adjusted so that the transmitting light intensities for the wavelengths λ1 and λ2 are equated. In the present measurement the base value thereof is adjusted at 800 nW. Subsequently, quantity of reflection light from the epoxy mold resin is measured. The homogeneous light having a peak wavelength λ1=660 nm from the light source unit 8 is introduced into the irradiation use optical fiber 6 through the like operation, passes the probe 5 and is irradiated onto a surface of the epoxy mold resin on a coil 2. The reflection light from the surface of the epoxy mold resin on the coil 2 is transferred via the light receiving use optical fiber 7 to the light quantity measurement unit 9 in which reflection light quantity I 1 ' is measured and the measurement result I 1 ' is output to the deterioration degree processing unit 10. In the deterioration degree processing unit 10, reflectance R660(=100×I 1 '/I 0 , I 0 =800) of the homogeneous light having peak wavelength 660 nm is calculated and is stored in a memory. Like operation is performed by making use of the homogeneous light having peak wavelength λ2=850 nm and in the deterioration degree processing unit 10, reflectance R850(=100×I 2 '/I 0 , I 0 =800) of the homogeneous light having peak wavelength 850 nm is calculated and is stored in the memory. With the thus obtained reflectances of the homogeneous lights having peak wavelengths 660 and 850 nm, reflection absorbance difference ΔAλ(=Aλ1-Aλ 2 ) between those of the two wavelengths or reflection absorbance ratio Aλ'(=Aλ1/A λ2) between those of the two wavelengths is determined. In the hard disk unit of the personal computer, reflection absorbance difference or reflection absorption ratio with respect to deterioration degree as shown in FIG. 5 and FIG. 9 is stored before hand in a form of master curves which are output to the deterioration degree processing unit 10 in which processing for comparison is performed on the stored function values and the reflection absorbance difference or the reflection absorbance ratio determined based on the actual measurement, and the deterioration degree thereof is judged.
(Embodiment 5)
Like embodiment 1, an embodiment 5 relates to a deterioration diagnosis device according to the present invention which is applied to an oil filled transformer and uses a halogen lamp irradiating continuous white color light as the light source unit 8.
At first wavelength dependency of the insulation oil is measured. The continuous light from a light source unit 8 is introduced via a spectroscope to an irradiation use optical fiber 6, reaches into a probe 5 as shown in FIG. 2, passes a half mirror 11 and thereafter is transmitted through the insulation oil having distance a.
The transmitted light is transferred via a light receiving unit 13 and a light receiving use optical fiber 7 to a light quantity measurement unit 9, wherein reference light quantities Iλ for respective wavelengths λ is determined. Although, the measurement range of the wavelength dependency is not lmited, a range of 400˜1500 nm is sufficient for the present embodiment. Subsequently, the wavelength dependency of the quantity of reflection light from an insulation paper is measured. The continuous light from the light source unit 8 is introduced into the irradiation use optical fiber 6 through the like operation, passes the probe 5 and is irradiated onto a surface of the insulation paper on a coil 2. The reflection light from the surface of the insulation paper on the coil 2 is transferred via the light receiving use optical fiber 7 to the light quantity measurement unit 9 in which reflection light quantity Iλ' is measured and the measurement result Iλ' is output to the deterioration degree processing unit 10. In the deterioration degree processing unit 10, reflectance Rλ(=100×Iλ'/Iλ) of the respective wavelengths is calculated and is stored in a memory. With the thus obtained reflectances of the respective wavelengths, reflection absorbance difference ΔAλ(=Aλ1-Aλ2) between those of any two wavelengths or reflection absorbance ratio Aλ'(=Aλ1/Aλ2) between those of any two wavelengths is determined. In the hard disk unit of the personal computer, reflection absorbance difference or reflection absorption ratio with respect to deterioration degree as shown in FIG. 5 and FIG. 9 is stored before hand in a form of master curves which are output to the deterioration degree processing unit 10 in which processing for comparison is performed on the stored function values and the reflection absorbance difference or the reflection absorbance ratio determined based on the actual measurement, and the deterioration degree thereof is judged and then is output as the measurement result such as to an external printer (not shown).
(Embodiment 6)
Like embodiment 5, an embodiment 6 relates to a deterioration diagnosis device according to the present invention which is applied to a liquid per-fluorocarbon filled transformer and uses a halogen lamp irradiating continuous white color light as a light source unit 8.
At first wavelength dependecy of the liquid per-fluorocarbon is measured. The continuous light from the light source unit 8 is introduced via a spectroscope to an irradiation use optical fiber 6, reaches into a probe 5 as shown in FIG. 2, passes a half mirror 11 and thereafter is transmitted through the liquid per-fluorocarbon having distance a.
The transmitted light is transferred via a light receiving unit 13 and a light receiving use optical fiber 7 to a light quantity measurement unit 9, wherein reference light quantities Iλ for respective wavelengths λ is determined. Although, the measurement range of the wavelength dependency is not limited, a range of 400˜1500 nm is sufficient for the present embodiment. Subsequently, the wavelength dependency of the quantity of reflection light from an insulation paper is measured. The continuous light from the light source unit 8 is introduced into the irradiation use optical fiber 6 through the like operation, passes the probe 5 and is irradiated onto a surface of the insulation paper on a coil 2. The reflection light from the surface of the insulation paper on the coil 2 is transferred via the light receiving use optical fiber 7 to the light quantity measurement unit 9 in which reflection light quantity Iλ' is measured and the measurement result Iλ' is output to the deterioration degree processing unit 10. In the deterioration degree processing unit 10, reflectance Rλ(=100×Iλ'/Iλ) of the respective wavelengths is calculated and is stored in a memory. With the thus obtained reflectances of the respective wavelengths, reflection absorbance difference ΔAλ(=Aλ1-Aλ2) between those of any two wavelengths or reflection absorbance ratio Aλ'(=Aλ1/Aλ2) between those of any two wavelengths is determined. In the hard disk unit of the personal computer, reflection absorbance difference or reflection absorption ratio with respect to deterioration degree as shown in FIG. 5 and FIG. 9 is stored before hand in a form of master curves which are output to the deterioration degree processing unit 10 in which processing for comparison is performed on the stored function values and the reflection absorbance difference or the reflection absorbance ratio determined based on the actual measurement, and the deterioration degree thereof is judged.
(Embodiment 7)
Like the embodiments 5 and 6, an embodiment 7 relates a deterioration diagnosis device according to the present invention which is applied to a SF 6 gas insulated transformer and uses a halogen lamp irradiorating continuous white color light as a light source unit 8.
At first wavelength dependency of the SF 6 gas is measured. The continuous light from the light source unit 8 is introduced via a spectroscope to an irradiation use optical fiber 6, reaches into a probe 5 as shown in FIG. 2, passes a half mirror 11 and thereafter is transmitted through the SF 6 gas having distance a.
The transmitted light is transferred via a light receiving unit 13 and a light receiving use optical fiber 7 to a light quantity measurement unit 9, wherein reference light quantities Iλ for respective wavelengths λ is determined. Although, the measurement range of the wavelength dependency is not limited, a range of 400˜1500 nm is sufficient for the present embodiment. Subsequently, the wavelength dependency of the quantity of reflection light from an insulation paper is measured. The continuous light from the light source unit 8 is introduced into the irradiation use optical fiber 6 through the like operation, passes the probe 5 and is irradiated onto a surface of the insulation paper on a coil 2. The reflection light from the surface of the insulation paper on the coil 2 is transferred via the light receiving use optical fiber 7 to the light quantity measurement unit 9 in which reflection light quantity Iλ' is measured and the measurement result Iλ' is output to the deterioration degree processing unit 10. In the deterioration degree processing unit 10, reflectance Rλ(=100×Iλ'/Iλ) of the respective light wavelengths is calculated and is stored in a memory. With the thus obtained reflectances of the respective wavelengths, reflection absorbance difference ΔAλ(=Aλ1-Aλ2) between those of any two wavelengths or reflection absorbance ratio Aλ'(=Aλ1/Aλ2) between those of any two wavelengths is determined. In the hard disk unit of the personal computer, reflection absorbance difference or reflection absorption ratio with respect to deterioration degree as shown in FIG. 5 and FIG. 9 is stored before hand in a form of master curves which are output to the deterioration degree processing unit 10 in which processing for comparison is performed on the stored function values and the reflection absorbance difference or the reflection absorbance ratio determined based on the actual measurement, and the deterioration degree thereof is judged.
(Embodiment 8)
Like the embodiments 5 through 7, an embodiment 8 relates to a deterioration diagnosis device according to the present invention which is applied to a resin mold dry type transformer and uses a halogen lamp irradiating continuous white color light as a light source unit 8.
At first wavelength depecdency of the light source is measured. The continuous light from the light source unit 8 is introduced via a spectroscope to an irradiation use optical fiber 6, reaches into a probe 5 as shown in FIG. 2, passes a half mirror 11 and thereafter is transmitted through the air gas having distance a.
The transmitted light is transferred via a light receiving unit 13 and a light receiving use optical fiber 7 to a light quantity measurement unit 9, wherein reference light quantities Iλ for respective wavelengths λ is determined. Although, the measurement range of the wavelength dependency is not limited, a range of 400˜1500 nm is sufficient for the present embodiment. Subsequently, the wavelength dependency of the quantity of reflection light from an insulation paper is measured. The continuous light from the light source unit 8 is introduced into the irradiation use optical fiber 6 through the like operation, passes the probe 5 and is irradiated onto a surface of the insulation paper on a coil 2. The reflection light from the surface of the insulation paper on the coil 2 is transferred via the light receiving use optical fiber 7 to the light quantity measurement unit 9 in which reflection light quantity Iλ' is measured and the measurement result Iλ'is output to the deterioration degree processing unit 10. In the deterioration degree processing unit 10, reflectance Rλ(=100×Iλ'/Iλ) of the respective wavelengths is calculated and is stored in a memory. With the thus obtained reflectances of the homogeneous lights having peak wavelengths, reflection absorbance difference ΔAλ(=Aλ1-Aλ2) between those of any two wavelengths or reflection absorbance ratio Aλ'(=Aλ1/Aλ2) between those of any two wavelengths is determined. In the hard disk unit of the personal computer, reflection absorbance difference or reflection absorption ratio with respect to deterioration degree as shown in FIG. 5 and FIG. 9 is stored before hand in a form of master curves which are output to the deterioration degree processing unit 10 in which processing for comparison is performed on the stored function values and the reflection absorbance difference or the reflection absorbance ratio determined based on the actual measurement, and the deterioration degree thereof is judged.
(Embodiment 9)
An embodiment 9 relates to a deterioration diagnosis method and device according to the present invention which makes use of light transmission loss difference between those for two wavelengths through an insulation oil as a parameter with the structure of the embodiment 1. At first quantities of transmission lights through air for respective wavelengths from the light source are respectively measured. Two kinds of LED light sources (λ1=660 nm, λ2=850 nm) are used as the light source unit 8. Reference light quantities Iλ1 and Iλ2 for the respective wavelengths, when the lights have transmitted through an air gap having distance a (cm) are respectively measured. Subsequently, quantities of transmission lights through the insulation oil are likely measured. Namely, quantity of transmission light Iλ' for the homogeneous light having peak wavelength of 660 nm through the insulation oil is measured and the measurement result Iλ1' is output to the deterioration degree processing unit 10, in which light transmission loss αλ1(=-10/a×log(Iλ1'/Iλ1), wherein unit is dB/cm) for the wavelength 660 nm is calculated and the calculation result is stored in a memory. Likely, the same operation is performed by making use of the homogeneous light having peak wavelength of 850 nm and in the deterioration degree processing unit 10 light transmission loss αλ2(=-10/a×log(Iλ2'/Iλ2), wherein unit is dB/cm) for the wavelength 850 nm is calculated and the calculation result is stored in the memory. With thus obtained light transmission losses for the wavelengths 660 and 850 nm, light transmission loss difference Δαλ(=αλ1-αλ2) is determined in the deterioration degree processing unit 10. In the hard disk unit of the personal computer light transmission loss difference with respect to deterioration degree is stored in advance in a form of master curves as illustrated in FIG. 6, which is output to the deterioration degree processing unit 10 in which processing for comparison is performed on the stored function values and the light transmission loss difference of the insulation oil determined based on the actual measurement, and the deterioration degree thereof is judged.
(Embodiment 10)
An embodiment 10 relates to a deterioration diagnosis method and device according to the present invention which makes use of light transmission loss difference between those for two wavelengths through an insulation oil as a parameter with the structure of the embodiment 5. At first quantities of transmission lights through air for the continuous white color light are respectively measured. A halogen lamp is used as the light source unit 8. Reference light quantities Iλ for the respective wavelengths, when the lights have transmitted through an air gap having distance a (cm), are respectively measured. Although, the range of wavelengths λ is not particularly limited a wavelength range of 400˜1500 nm is sufficient for the present embodiment. Subsequently, quantities of transmission lights through the insulation oil are likely measured. Namely, quantity of transmission light Iλ' for the wavelength λ through the insulation oil is measured and the measurement result Iλ' is output to the deterioration degree processing unit 10, in which light transmission loss αλ(=-10/a×log(Iλ'/Iλ), wherein unit is dB/cm) for a wavelength is calculated and the calculation result is stored in a memory. In the like manner light transmission losses for respective wavelength are obtained. With thus obtained light transmission losses for the respective wavelengths, light transmission loss difference Δαλ(=αλ1-αλ2) between those of any two wavelengths is determined in the deterioration degree processing unit 10. In the hard disk unit of the personal computer light transmission loss difference with respect to deterioration degree is stored in advance in a form of master curves as illustrated in FIG. 6, which is output to the deterioration degree processing unit 10 in which processing for comparison is performed on the stored function values and the light transmission loss difference of the insulation oil determined based on the actual measurement, and the deterioration degree thereof is judged.
According to the present invention, a deterioration diagnosis method and device can be obtained which permits diagnosis of deterioration degree of such as mineral oil series insulation oil, insulation medium such as liquid per-fluorocarbon and celllose series insulation material used for an oil filled electrical machine and apparatus, a resin material for a resin mold insulation type electrical machine and apparatus and an insulation material for a gas such as SF 6 gas insulation type electrical machine and apparatus without destruction thereof used in an electrical machine and apparatus during the operation thereof without stopping the operation. | In order to diagnose non-distructively the deterioration degree of such as insulation oil and insulation paper during operation of an oil filled electrical machine and apparatus without stopping the operation thereof, a deterioration degree disgnosis method for the oil filled electrical machine and apparatus makes use of optical fibers (6, 7) and oil immersed probe (5) and diagnoses the deterioration degree of an insulation paper non-distructively based on reflection absorbance difference between those for any two wavelengths of the insulation paper. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to the regeneration of a partially spent catalyst used in the synthesis of hydrocarbons from a synthesis gas. In one aspect, the invention relates to regenerating Fischer-Tropsch catalysts used in slurry reactor processes. In still another aspect, the invention relates to the regeneration of a Fischer-Tropsch catalyst in external regenerating vessels.
2. Brief Description of the Prior Art
The production of hydrocarbons from synthesis gas (H 2 and CO) is well-known and is described at length in the patent and technical literature. Although fixed bed, fluidized bed, entrained bed, and ebullating bed reactors have been used with a variety of catalysts, the slurry reactor process has received considerable attention in recent years.
In the slurry reactor process, finely divided catalyst is suspended in a heavy oil (e.g., paraffinic hydrocarbon) by bubbling synthesis gas through the reactor. The hydrocarbon reaction products are recovered in the overhead stream and from a slurry discharged from the reactor.
One of the problems associated with the slurry reactor process is that the activity of the catalyst deteriorates with use. The reason for the deterioration is not fully understood but is believed to be due in part to contaminants and reaction products which reversibly deactivate the catalyst.
In order to maintain an effective operation, the spent catalyst must be regenerated or replaced from time to time. (The terms “regenerate”, “reactivate”, and “rejuvenate” are used herein to mean the same thing: to increase the activity of the reversibly deactivated catalyst.)
Processes for regenerating Fischer-Tropsch catalysts used in slurry reactor processes are described in the following patents:
(a) U.S. Pat. No. 5,260,239 discloses a process wherein an external rejuvenation vessel is used to continuously receive partially spent catalyst slurry from a synthesis reactor vessel with the catalyst being rejuvenated by the passage of hydrogen therethrough in the rejuvenation vessel. The catalyst flow between the vessels is solely by gravity.
(b) U.S. Pat. No. 5,288,673 discloses a catalyst rejuvenation system comprising vertical draft tubes immersed in the slurry within the reactor. Hydrogen is passed upwardly through the draft tubes carrying catalyst slurry with it. Rejuvenated catalyst is ejected at the top of each tube into the top of the slurry reactor. Other draft tube rejuvenations are disclosed in U.S. Pat. No. 5,268,344.
(c) U.S. Pat. No. 5,283,216 discloses a method of rejuvenating a Fischer-Tropsch catalyst by passing hydrogen through the catalyst suspended in a liquid hydrocarbon.
(d) U.S. Pat. No. 5,811,363 discloses a catalyst regenerator for slurry reactors wherein the regenerator includes means for separating regenerated off gas from the regenerated catalyst.
(e) U.S. Pat. No. 5,811,468 discloses a catalyst regenerator for a slurry reactor wherein the catalyst slurry is passed through a gas disengaging zone and then into a catalyst regenerating tube.
(f) U.S. Pat. No. 5,817,701 discloses a process for regeneration of catalysts used in Fischer-Tropsch reactors of H 2 and CO, wherein CO is purged from the reactor prior to introduction of H 2 regeneration gas.
(g) U.S. Pat. No. 5,821,270 discloses a slurry reactor catalyst regeneration process wherein the slurry is passed successively through at least two regeneration stages.
The above U.S. Patents are representative of recent patents relating to slurry regeneration by hydrogen, either in the reactor or in a separate regeneration vessel or tube, and are hereby incorporated in their entirety by reference.
The regeneration of Fischer-Tropsch catalyst by hydrogen, however, has long been known for other types of reactors. For example, U.S. Pat. No. 2,414,276 discloses the use of hydrogen to regenerate a particulate catalyst suspended in a gas. The regeneration is continuous and carried out in a vessel external of the reactor. Another early U.S. Pat. No. 2,670,364, relating to Fischer-Tropsch fluidized bed reactors, discloses an external hydrogenation vessel for regenerating catalyst withdrawn from the reactor. These patents are also incorporated in their entirety by reference.
SUMMARY OF THE INVENTION
The regeneration of a partially deactivated synthesis gas particulate catalyst is carried out in a regeneration system comprising two alternating regeneration vessels (stations). The partially deactivated particulate catalyst, typically a supported catalyst, is alternately passed for regeneration to one of the two vessels. The use of alternate regeneration vessels permits a quantity of the partially deactivated catalyst to be flowed from the reactor to a first regeneration vessel as a like quantity of regenerated catalyst is returned to the reactor from a second regeneration vessel so that the reactor may be operated continuously at substantially the same level.
The catalyst is preferably a cobalt catalyst supported on a refractory oxide and suspended in a hydrocarbon liquid to form a slurry. The slurry containing the catalyst is treated in each regeneration vessel or an associated regeneration system with a regeneration gas, preferably hydrogen, or by other suitable regenerating techniques. When applied in the regeneration of a catalyst in a slurry, the alternate use of regenerating vessels according to the present invention results in the slurry volume in the reactor remaining substantially constant during its continuous operation.
Thus, the process of the present invention has characteristics of both continuous and batch processes. The slurry reactor operation is continuous during catalyst regeneration and the catalyst in the slurry is regenerated in batches by alternating the regenerating vessels. Each regeneration station preferably includes a single vessel, but each vessel may serve as a regenerator alone or in combination with other vessels.
The preferred regeneration system comprises two vessels having their inlets and outlets connected to the reactor, valved flow lines for selectively controlling slurry flow between the reactor and each vessel, and regeneration gas facilities for treating the slurry in each vessel.
BRIEF DESCRIPTION OF THE DRAWING
The FIGURE is a schematic flow diagram of a slurry reactor provided with an external catalyst regeneration system of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The method and apparatus of the present invention will be described with reference to the FIGURE.
Although the invention is described with emphases on a Fischer-Tropsch slurry reactor, it is to be understood that this description is for purposes of illustration only, and that the principles embodied in the invention are equally applicable to other reactor systems and other particulate catalyst regenerating systems.
A Fischer-Tropsch reactor 10 receives a synthesis gas through a feed line 11 and an internal distributor such as a sparger 12 . The synthesis gas comprises H 2 and CO, and may contain other gases such as N 2 and CO 2 . The mole ratio of the reactants H 2 and CO may range within relatively wide limits depending on the desired product, but normally will be between 3:1 to 1:1, preferably 2:1. The reactor 10 may also contain internal heat exchange tubes (not shown) which conduct water and steam through reactor 10 and provide temperature control therefor.
During steady state operations, the reaction of H 2 and CO in the presence of a Fischer-Tropsch catalyst produces a heavy hydrocarbon liquid phase 13 and a gas stream. The gas is withdrawn through an overhead line 16 and further processed downstream.
A liquid level 15 in reactor 10 , controlled by a weir 17 , is generally maintained slightly above a top of weir 17 . The space within reactor 10 above liquid level 15 serves as a degassing zone. The hydrocarbon liquid has a finely divided Fischer-Tropsch catalyst suspended therein forming a slurry. The synthesis gas entering near the bottom of reactor 10 bubbles through the slurry keeping the catalyst particles uniformly suspended in the hydrocarbon liquid. The slurry in the reactor thus is a three-phase slurry comprising hydrocarbon liquid, synthesis gas and gas reaction products, and finely divided catalyst solids. The volume ratios of the phases within reactor 10 may vary within relatively wide ranges depending on several factors, such as reactor operating conditions, desired products, type of catalyst, etc. The following, however, is representative of the phases in the reactor:
Liquid phase (heavy hydrocarbon liquid): from 30 to 90 vol %
Gas phase (synthesis gas and gas reaction products): from 5 to 40 vol %
Solid phase (catalyst particles): from 5 to 30 vol %
The hydrocarbon liquid is a heavy hydrocarbon (mainly C 10 and higher) reaction product of the Fischer-Tropsch reaction and is principally mixed paraffinic hydrocarbons.
The catalyst used in the Fischer-Tropsch reaction may be a Group VIII metal, preferably cobalt or iron and most preferably cobalt. The cobalt catalyst is preferably a supported catalyst wherein the cobalt is supported on a Group IV B oxide support having an average particle size from about 10 to about 100 microns. Preferred supports include refractory oxides, silica, alumina, aluminates, titania, and the like.
Methods of manufacturing, promoting and using Group VIII metal supported catalysts are well known to those skilled in the art and are described at length in the patent and technical literature.
The gaseous products may include middle distillate paraffins. The gas stream withdrawn from the reactor may also include water and unreacted components of the synthesis gas.
As shown in the FIGURE, two catalyst regenerating vessels 31 and 32 are connected in parallel to reactor 10 . The preferred embodiment of the regeneration system described herein employs one vessel at each station (vessel); however, it is contemplated that more than one vessel can be used at each station, as for example in stations where regeneration is by more than one treatment. Two or more vessels at each station could be used in such regeneration treatments.
During an illustrative hydrogen regeneration operation, the degassed slurry overflowing weir 17 passes through a reactor discharge line 18 and downstream through a line 19 for further processing, product separation, return to a lower part of reactor vessel 10 and the like. A valve 20 controls the flow through line 19 .
A line 21 leads from line 18 to vessels 31 and 32 . Although valve 20 in line 19 may be used to divert all or part of the slurry exiting reactor 10 through line 18 to line 21 , it is preferred that valve 20 remain at least partially open during normal regeneration to regulate flow through line 19 . Note that line 21 leading to the regeneration system may be connected directly to the reactor 10 to receive slurry overflow from weir 17 .
Although it is not necessary for purposes of the present invention, it is preferred that vessels 31 and 32 are identical in shape and construction and are located side-by-side to facilitate their alternating use as described below. For most operations, the volume of each regenerating vessel 31 and 32 may be from about 5 to about 30%, and preferably about 5 to about 20%, of the effective volume of reactor 10 .
Vessel 31 is fed by a line 33 provided with a valve 34 ; and vessel 32 is fed by a line 36 provided with a valve 37 . Lines 33 and 36 are each in fluid communication with line 21 as described above. The outlets of vessels 31 and 32 are provided with valved discharge lines 38 and 39 , respectively (valve 41 in line 38 and valve 42 in line 39 ). A line 40 returns the slurry from lines 38 and 39 to a lower part of reactor 10 . Lines 38 and 39 may be provided with check valves (not shown) to prevent backflow into regenerating vessels 31 and 32 .
A regenerating gas (e.g., hydrogen) is introduced into the bottom of a selected one of vessel 31 and 32 by lines 43 and 44 , respectively. Valve 46 in line 43 and valve 47 in line 44 permits selective flow of regenerating gas to each of vessel 31 and vessel 32 . Line 48 connected to lines 43 and 44 delivers hydrogen from a source (not shown).
The preferred regeneration gas is hydrogen, but other gases, such as nitrogen, may be used alone or in combination with hydrogen.
For purposes of illustration, the regeneration system of the present invention will be described with reference to hydrogen as the regeneration gas, but it is to be understood that this is a nonlimiting example. The hydrogen can be supplied by a generator or from another part of the plant.
Vessels 31 and 32 are provided with valved gas exhaust lines 51 and 52 (valve 53 for line 51 and valve 54 for line 52 ). Exhaust gas streams withdrawn from vessels 31 and 32 are flowed through a line 56 provided with a valve 57 . The exhaust gas which includes unreacted hydrogen, reaction products, and the like may be further processed to recover hydrogen for recycling to the regeneration system.
Each of vessels 31 and 32 in its regeneration mode operates in the same way: degassed slurry flows by gravity from reactor 10 into a top portion of a regenerating vessel (e.g. vessel 31 ) with hydrogen (or other dispersing or regenerating gas) simultaneously entering a bottom portion of vessel 31 . The hydrogen or other dispersing gas bubbling through the slurry in vessel 31 maintains the catalyst particles suspended therein. In this mode, slurry inlet valve 34 and hydrogen valve 46 are open and slurry outlet valve 41 is closed. The slurry fills vessel 31 to a selected level, at which time slurry inlet valve 34 is closed. The flow of hydrogen through the active vessel continues or is initiated and maintained until catalyst regeneration is complete, with valves 46 , 53 and 57 being open.
A novel feature of the present invention is the alternating operation of the regenerating vessels 31 and 32 . This enables the volume of the reactor (slurry, catalyst and gas bubbles) to remain substantially the same. Thus, catalyst regeneration need not interrupt the operation of reactor 10 . As noted earlier, it is preferred to operate reactor 10 continuously without interruption.
In normal operation (without catalyst regeneration), synthesis gas is bubbled through slurry 13 in reactor 10 . Degassed liquid hydrocarbon slurry overflows weir 17 and gaseous hydrocarbon exit through overhead line 16 . In this phase of the operation, valve 20 is open and regeneration system inlet valves 34 and 37 are closed. Liquid hydrocarbons may be separated from the slurry from weir 17 with the remaining slurry being returned to reactor 10 or passed to further processing.
For startup of catalyst regeneration, both vessels 31 and 32 will be empty of slurry. To initiate regeneration, as for example in vessel 31 , valve 34 is opened and valves 41 and 37 will be closed. Degassed slurry flows through lines 18 , 21 and 33 into vessel 31 . Hydrogen may simultaneously be flowed upwardly through vessel 31 (valves 46 , 53 and 57 are open) to maintain the catalyst particles suspended in the hydrocarbon liquid. When the slurry in vessel 31 reaches the desired level, inlet valve 34 is closed. Hydrogen flow is continued through vessel 31 for a period of time to regenerate the catalyst therein.
When the catalyst in vessel 31 is regenerated to the desired extent, the operation of alternating vessels 31 and 32 may begin. Vessel 31 outlet valve 41 is opened, and vessel 32 inlet valve 37 is opened. Regenerated slurry flows from vessel 31 and returns to reactor 10 through lines 38 and 40 . This displaces a like amount of slurry over weir 17 and accelerates the flow of degassed slurry into vessel 32 through lines 18 , 21 and 36 . Note that in the preferred mode of operation, degassed slurry may continue to flow through line 19 .
The slurry in vessel 31 will not all flow back into vessel 31 by gravity alone.
Flow from vessel 31 to reactor 10 may be accelerated and completed by injection of pressurized gas above the slurry therein. This can be achieved by closing hydrogen exhaust valve 53 while continuing the injection of hydrogen into vessel 31 through line 43 . The hydrogen accumulates in the upper part of vessel 31 and develops sufficient pressure to force the regenerated slurry from vessel 31 into reactor 10 . Alternatively, a separate gas (e.g. nitrogen) may be injected through a line 60 to displace with the slurry from either or both of the vessels.
Simultaneous with the emptying of slurry from vessel 31 , vessel 32 is being filled. It is preferred that the amount of degassed slurry flowing into vessel 32 is substantially equal to that displaced from vessel 31 .
During the filling of vessel 32 , hydrogen can be injected therethrough to maintain the catalyst particles in suspension. With vessel 32 filled to the desired level, the hydrogen flow is continued through vessel 32 until the catalyst is sufficiently regenerated.
Regenerated catalyst slurry is pressure flowed out of vessel 32 into a lower part of reactor 10 while simultaneously therewith, slurry with partially deactivated catalyst is flowed into vessel 31 . As in the case of discharging slurry from vessel 31 , discharging slurry from vessel 32 may be accelerated and completed by the use of pressurized hydrogen or other gas injected into vessel 32 .
Catalyst regeneration may continue by alternating slurry flow to and from vessels 31 and 32 in the manner described above.
The operating parameters of the regeneration system of the present invention will depend upon a variety of factors, as known to those skilled in the art, including reactor and vessel volumes, catalyst, reaction products, operating temperature, pressure, and synthesis gas quality, feed rates, to name but a few of the variables.
The catalyst regeneration can begin when the catalyst has deteriorated sufficiently to reduce catalyst activity below a desired level. Regeneration is designed to maintain the activity of the catalyst in reactor 10 at an overall level from about 50 to about 90%, preferably from about 70 to about 90% of its original activity. The operation of the regeneration vessels preferably maintains the overall activity of the catalyst in the reactor at a substantially constant desired level. This level can be changed by controlling the operation of the regeneration system (e.g. hydrogen flow, treatment times and rates, etc.)
Further, the catalyst regeneration system discussed above for use in hydrogen regeneration can also be used when different regeneration systems are required. In such instances it may be desirable to conduct these operations in separate vessels, which is readily accomplished by simply withdrawing the volume of catalyst from one of the two regeneration vessels and completing the regeneration step and thereafter returning the withdrawn catalyst to one or the other of the regeneration vessels for return to the reactor as discussed above. Other steps may be used and other regeneration systems may be used if considered necessary or desirable. It is contemplated, however, that the use of the present system, which allows the withdrawal of a controlled amount of catalyst-bearing slurry from the reactor, while returning an equal volume of regenerated slurry to the reactor will be effective in such process variations. The fact that the treatment requires more than one vessel in no way detracts from the ability of the present system to remove partially deactivated catalyst from the reactor and simultaneously return a like quantity of regenerated catalyst to the reactor.
While the present invention has been described by reference to certain of its preferred embodiments, it is respectfully pointed out that the embodiments described are illustrative rather than limiting in nature and that many variations and modifications are possible within the scope of the present invention. Many such variations and modifications may be considered obvious and desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. | A method of regenerating a finely-divided particulate catalyst involves the use of an external regeneration system comprising first and second regeneration stations. The method is particularly adapted to regenerating supported catalysts used in Fischer-Tropsch slurry reactors. A slurry-containing partially spent catalyst is flowed from the reactor and alternately regenerated in one of the first and second regeneration stations. The alternate use of the stations for catalyst regeneration permits one station to receive partially deactivated slurry from the reactor while the other station returns regenerated slurry to the reactor. The operation of the reactor thus may be continuous. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to ski devices or assemblies and, more particularly, is directed towards a skiing unit having a single runner upon which is mounted a seat for an operator.
2. Description of the Prior Art
My prior U.S. Pat. No. 3,325,179 teaches a ski device which has a single runner and a shock-absorbing seat structure and which is capable of operation on snow or other suitable surfaces, including water.
My prior device includes a single, relatively narrow runner 10 upon which is mounted an elongated strut 18. Mounted on the strut 18, in turn, is a forward bracket 30, a center bracket 138, and a rear bracket 114 for respectively supporting the front of the unit 50, an anti-sway linkage, and a double-acting shock-absorber. Mounted on the top of the unit 50 is a seat structure 62, and a pair of fenders 86 extended forwardly below the seat 62 adjacent the chassis 50.
The device described in my earlier patent suffers from several deficiencies. One of the major disadvantages with respect to my prior art structure is that the strut 18, mounted along almost the entire length of the runner 10, does not permit the runner 10 to flex or bend sufficiently during use. Since skis, and particularly modern skis which are constructed of fiberglass and other synthetic materials, are particularly designed to flex while in use along their entire lengths, and the provision of the strut 18 of my prior art device inhibits such flexure, the overall performance of the unit suffers greatly.
Another disadvantage of my earlier design is that the placement of the support brackets for the anti-sway linkage and the shock-absorber also inhibits ski flexure and contributes to a less efficient operating unit. Although originally believed necessary for proper support of the chassis and seat, it is clear to me that the rearward placement of the brackets detracts from, rather than enhances, the overall operation and use of the device.
Another disadvantage of the prior art device described in my earlier patent is that it can not be easily dismantled, and it is bulky, heavy, and otherwise difficult to handle, store, transport and carry. The heavy weight of the unit also detracts from performance, rather than adds stability as originally anticipated.
Another disadvantage with respect to my early design is that the single shock-absorber frequently is of insufficient strenth to handle heavy operators without bottoming out during use.
I realized, therefore, that a major overhaul of my prior design would be necessary to overcome the deficiencies and difficulties pointed out above, and the present invention is advanced as a result of such effort.
OBJECTS AND SUMMARY OF THE INVENTION
It is therefore a primary object of the present invention to provide a new and improved ski device which overcomes all of the disadvantages noted above with respect to my prior art design.
Another object of the present invention is to provide a new and unique ski device whose design, operation, feel, and performance is more closely analogous to that of a foot-operated ski than my prior design.
A further object of the present invention is to provide a new and improved ski device having a single runner and a seat structure articulated thereto and which permits the ski to flex along its entire length, thereby taking advantage of normal, expected ski action, for improved performance and control.
A still further object of the present invention is to provide a new and improved ski device having a seat structure and associated shock-absorbing means which is able to accommodate heavier loads than my prior art design.
An additional object of the present invention is to provide a novel and unique ski device of the same general character as my prior art device described above, but of a radically improved design, which is strong, durable, and easily assembled and disassembled for storage, shipping or transport.
A still further object of the present invention is to provide a unique ski device which operates in a fashion analogous to a regular foot-mounted ski, and thereby takes advantage of the design parameters of a regular ski.
Another general object of the present invention is to provide an improved ski device which is more sturdy, streamlined, structurally sound and provides better action, control and performance than my prior art device or any similar device of the same general character.
The foregoing and other objects are attained in accordance with one aspect of the present invention through the provision of a ski device, which comprises an elongated runner, seating means pivotally mounted at its forward end to the runner, anti-sway means pivotally mounted between the seating means and the runner, and shock-absorbing means pivotally mounted between and extending downwardly and forwardly from the rear portion of the seating means to the runner. The anti-sway means also preferably extends downwardly and forwardly from the seating means to the runner. The shock-absorbing means and the anti-sway means are preferably pivotally mounted to the runner at positions forwardly of the rearmost portion of the seating means in such a fashion that the distance between the rearmost and forwardmost pivotable mount on the runner is approximately the same as the distance between the front and rear foot bindings of a regular, foot-mounted ski.
In accordance with another aspect of the present invention, there are preferably further provided first, second and third mounting bracket means fastened to the upper surface of the runner to which are respectively pivotally mounted the forward end of the seating means, the anti-sway means and the shock-absorbing means. It may be said that the distance between the first and third mounting bracket means is on the same order as the distance between the toe and heel bindings of a regular, foot-mountable ski in such a fashion that the second and third mounting bracket means are positioned forwardly of the rearmost portion of the seating means. The mounting bracket means preferably includes hinged means for fastening same to the runner to enable the latter to flex in a normal fashion. In one embodiment, the hinged means comprises a first hinge for fastening the first mounting bracket means to the runner, and a second hinge for fastening the second and third mounting bracket means to the runner. In an alternate embodiment, the hinged means comprises a first hinge for fastening the first and second mounting bracket means to the runner, and a second hinge for fastening the third bracket means to the runner.
In accordance with another aspect of the present invention, the seating means comprises a vertically oriented chassis and a seat mounted to the top of the rear portion of the chassis, which portion is inclined downwardly and rearwardly from the central portion of the chassis and includes mounting bracket means for removably fastening the seat thereto. In one embodiment, the mounting bracket means comprises a pair of L-shaped brackets having one arm fastened to the chassis along the top of its rear portion, and a second arm forming a planar mount for removably attaching the seat. In an alternative embodiment, the mounting bracket means comprises a pair of L-shaped brackets having one arm fastened to the underside of the seat and a second arm which forms a mounting flange for removably fastening the seat to the chassis.
In accordance with other aspects of the present invention, the seat preferably comprises a bucket seat and includes a pair of handle means spaced forwardly from the front portion of the seat. Means are connected to the handle means of the seat for removably fastening a carrying strap thereto.
In accordance with another aspect of the present invention, the top of the front portion of the chassis is inclined downwardly and forwardly from the central portion thereof and there are further provided a pair of fenders hingedly mounted to the chassis along the top of its front portion. Each of the fenders is substantially planar and includes a rear edge which extends underneath the seat. The seat preferably includes means fastened to the underside thereof for releasably engaging the fenders which, in a preferred form, comprises a pair of spring-loaded clamps.
In accordance with other aspects of the present invention, the shock-absorbing means is pivotally mounted to the chassis underneath the seat and can comprise either a single shock-absorber or a pair of shock-absorbers symmetrically mounted about the vertical center plane of the chassis.
In accordance with another aspect of the present invention, a pair of separate, short runners having foot bindings thereon may be provided for use by an operator of the ski device for enhancing stability, poise and performance of the entire unit.
BRIEF DESCRIPTION OF THE DRAWINGS
Various objects, features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description of the present invention when considered in connection with the accompanying drawings, in which:
FIG. 1 is a perspective view of a preferred embodiment of the ski device of the present invention;
FIG. 2 is a partially broken, side view in elevation of the preferred embodiment illustrated in FIG. 1;
FIG. 3 is a rear view of the preferred embodiment illustrated in FIG. 2;
FIG. 4 is a partially broken, top view of the preferred embodiment illustrated in FIG. 3;
FIG. 5 is an enlarged, sectional view of certain components which comprise the anti-sway linkage of the present invention, taken along line 5--5 of FIG. 2;
FIG. 6 is another sectional view of FIG. 2 taken along line 6--6 thereof;
FIG. 7 is a side view in elevation which illustrates an alternative embodiment of the present invention; and
FIG. 8 is a rear view which illustrates yet another alternative embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The ski device of the present invention is indicated generally by reference numeral 10 and, as will be described in greater detail hereinafter, comprises an efficient, controlable and comfortable device including a seat structure which is articulated to a single runner for tilting forwardly and rearwardly, as well as upwardly, relative to the runner, in a vertical plane, in response to variations in the contours of the medium over which the ski device 10 is operated, the movement of the seat structure being snubbed and controlled by shock-absorbing means connected between the seat assembly and the runner.
Referring more particularly to the drawings, the runner is indicated by reference numeral 12 and includes a forward, upwardly curved front end 14 and a rear end 16. The runner 12 of the ski device 10 may be comprised of any commercially manufactured ski, or may consist of a runner especially designed for the present invention. The material of runner 12 may be of any suitable natural or artificial material and may either be solid or laminated of one material or of a combination of various materials, either natural or synthetic. The runner 12 may have formed along its length either a side or bottom camber, and may have a centered bottom groove or grooves, as is common in many commercially available skis.
Mounted somewhat rearwardly of the central section 18 of the runner 12 is an upright, vertically oriented chassis 20 which includes, as perhaps best seen in FIG. 2, a forward downwardly curved edge 22, a central, rearwardly curved lower edge 24, a rear, relatively straight edge 26, a rearmost edge 27, and an upper edge 28 which extends downwardly and forwardly from the central, upper portion of the chassis 20. The chassis 20 may be constructed of any suitable, preferably light-weight, material of sufficient strength. The specific construction of chassis 20 may be solid, tubular, skeletal, or consist of a panel-covered framework, hollow body, or the like, and may be constructed of natural, laminated, synthetic or composition materials.
Fastened somewhat rearwardly of the central portion 18 of the runner 12 is a forward mounting bracket which is indicated generally by reference numeral 30. Mounting bracket 30 includes a hinged base plate 31, pivot pins 32, a hinge member 33, and a main pivot pin 34 to which the lower end of the forward edge 22 of chassis 20 is pivotally mounted. As seen in FIG. 6, the lower portion of the forward edge 22 is connected via connector 37 to a pivot bracket 39 through which pin 34 extends to pivotally secure the forward portion of the chassis 20 to the runner 12. The hinges 31 and 33, along with pivots 32, enables the chassis 20 to be more firmly attached to the ski 12 and at the same time permits a certain degree of flexibility in the ski at this position, to enhance performance of the unit.
Connected to the rear portion of the central, rearwardly curved lower edge 24 of the upright chassis 20 is another bracket 36 to which the upper arm 38 of an anti-sway linkage is pivotally attached via pivot bolt 46. As seen also in FIG. 5, the upper arm 38 includes a laterally offset lower end 49. The lower arm 40 of the anti-sway linkage includes a laterally offset upper end 41 which is pivotally secured to the offset lower end 49 of upper arm 38 via a pivot bolt 50. The lower arm 40 of the anti-sway linkage is pivotally coupled to a lower bracket 42 via a pivot bolt 48. The bracket 42 is, in turn, mounted to the hinge 35 via pivot 43 for permitting flexure of the central portion 18 of the runner 12 at this position. The anti-sway linkage inhibits motion of the ski device 10 out of the plane of the chassis 20, thereby inhibiting side-to-side motion while enhancing vertical, forward and rearward motion.
In FIG. 3, reference numerals 51 and 53 indicate the side walls of chassis 20 between which the rear edge 27 is positioned. Below edge 27, side walls 51 and 53 are spaced to accommodate the upper end of a single shock absorber 58 via a pivot bolt 56. The lower end of the shock absorber 58 is pivotally mounted to the runner 12 via a bottom bracket 62 and its associated pivot bolt 60. Bracket 62 is mounted to runner 12 preferably via a hinged plate 61, although the brackets 42 and 62 may together be mounted on a single lower hinge, as illustrated in FIG. 2.
Note in FIG. 2 that the single shock absorber 58 extends downwardly and forwardly from the rear 27 of the chassis to the runner 12 in such a fashion that its forward edge 64 is substantially parallel to the rear edge 66 of the upper link 38 of the anti-sway linkage, as well as to the edge 26 of the chassis 20. This positioning of the rear shock absorber 58, as well as of the anti-sway linkage, provides greatly improved performance of the ski device 10 of the present invention since the distance between the forwardmost positioned bracket and the rearmost positioned bracket is about the same as the distance between the toe and heel bindings of a normal, foot-mounted ski. Accordingly, the runner 12 will react to the operator of the unit 10 in much the same fashion as would the same runner to a foot skier. The runner 12 is permitted full flexure forwardly and rearwardly of the respective brackets, and some flexture therebetween, as a result of the hinges, and of the method of mounting them.
For example, the distance between the forwardmost bracket 30 and the rearwardmost bracket 62 is approximately fourteen to sixteen inches, which is on the same order as the distance between regular ski boot bindings, and are mounted somewhat rearwardly of the central portion 18 of the runner 12 to permit the runner to flex its full length forwardly and rearwardly of the brackets and thereby function and respond in much the same manner as it would for a foot-mounted skier. The curvature provided by edges 22, 24 and 26 of the chassis 20 provides a more stream-lined, lighter structure, without sacrificing strength, rigidity or integrity.
Referring now most particularly to FIGS. 3 and 4, but also illustrated in FIGS. 1 and 2, a pair of substantially triangular, planar fenders 68 and 70 extend just under the top edge 28 of the chassis 20. The purpose of the fenders 68 and 70 is to protect the rider from snow spray, water spray, or the like. The fenders 68 and 70 are respectively secured by a pair of piano hinges 72 and 74 which are mounted along the upper edge 28 of the chassis 20. Provision of the hinges 72 and 74 permit the planar fenders 68 and 70 to be lowered substantially adjacent the side walls 51 and 53 of the chassis 20 for easy transport, as will be explained in greater detail hereinafter.
A seat is indicated generally by reference numeral 76 and may be seen to preferably comprise a bucket seat 95 for added confort, stability and control. The seat may be constructed of padded foam rubber covered by a flexible, weather-resistant material, or may be constructed of fiberglass, plastic, natural or synthetic material. The bucket style is preferred so that the inner portion 95 of the seat secures the buttocks of the rider against accidental displacement rearwardly during use. The seat 76 is attached to the chassis 20 in such a fashion so as to be angled downwardly from the central portion of the chassis to the rear in relation to the horizontal plane of the unit.
The seat 76 is, in a preferred mode, secured to the chassis by means of a pair of L-shaped brackets 52 and 54 (FIG. 3) which are themselves secured to the side walls 51 and 53 of chassis 20 and include upper, horizontally extending, planar flanges 78 and 80 through which securing means, such as, for example, thumb screws 82 and 84, may be positioned to secure seat 76 onto the brackets 52 and 54. Alternatively, as illustrated, for example, in FIG. 8, the L-shaped brackets 52 and 54 may be secured to the underside of the seat 76, and the seat may be secured by placing thumb screws 86 and 88 through the vertical flanges 85 and 87 of the brackets to the side walls 51 and 53 of the chassis 20.
Referring back to FIGS. 3 and 4, a pair of spring-loaded hinges 90 and 92 are positioned on the underside of seat 76 near the forward edge thereof for securing the rear edges 91 and 93 of the fenders 68 and 70 in their upper position. It may be appreciated from the foregoing that the seat 76 is easily removable which facilitates transport, storage and shipping of the unit. To break down the ski device 10, the spring-loaded hinges 90 and 92 are pulled back, and the fenders 68 and 70 are dropped along their hinges 72 and 74 so as to be adjacent to the sides 51 and 53 of the chassis 20. The seat 76 may then be easily detached by unscrewing thumb screws 82 and 84, or 86 and 88, as may be the case, and the entire seat removed for transport.
Positioned on the forward edges of the seat 76 are a pair of handles 98 and 100 which are spaced from the forward edge 96 of the frame 94 of the seat 76 to facilitate grasping thereof. Positioned between the handles 98 and 100 and the respective forward edge 96 of seat 76 are a pair of mounting brackets or spurs 102 to one or both of which may be attached or detached a safety strap 104 which is provided to facilitate carrying of the unit up a ski lift, for example. The spur 102 renders the strap 104 interchangeable from one handle to the other, as may be desired.
Referring now to FIG. 8, an alternative embodiment of the present invention is illustrated. In this embodiment, a pair of shock absorbers 106 and 108 are symmetrically positioned about the vertical plane through the chassis 20. The provision of two shock absorbers 106 and 108 provides additional force-restraining movement of the unit for heavier operators to prevent bottoming out of the device during use. The shock absorbers 106 and 108 may be connected to a dual lower mounting bracket 110 having a pair of downwardly angled pins 109 and 111, and may be connected to respective upper mounting pins 112 and 114 which extend laterally from side walls 51 and 53 of the chassis. The construction of the unit of FIG. 8 may, in all other respects, be the same.
Referring now to FIG. 7, another alternative embodiment of the present invention is illustrated in which the individual mounting brackets 30 and 42 of FIG. 1 are combined into a single mounting bracket 120 for pivotally connecting both the forward portion 22 of the chassis 20 and the lower arm 40 of the anti-sway linkage. The pivot bolts are again indicated in FIG. 7 by reference numerals 34 and 48, respectively, while reference numeral 122 indicates a mounting plate hinged at 124 for the mounting bracket 120. The shock absorber 58 is, in turn, mounted to a single rear bracket 126 which is connected to the central portion 18 of the runner 12 in approximately the same position as would bracket 62 of FIGS. 1 and 2. It may also be appreciated that the dual bracket 120 of FIG. 7 may be utilized equally effectively in conjunction with the dual shock absorber embodiment of FIG. 8.
Illustrated in FIG. 1 are a pair of short side skis 128 and 130 each of which include conventional toe and heel bindings on the top surface thereof to permit an operator of the device 10 to wear same during operation. The skis 128 and 130, on the order of eighteen to twenty inches in length, enhance stability, poise and performance, and are extremely desirable. In operation, they are kept parallel to the main runner 12, approximately three inches from the outer edges thereof. The skis 128 and 130 are not necessarily used for controlling the device 10 of the present invention, but are simply intended to ride over the surface lightly to enhance overall performance.
In operation, the rider places himself firmly in the seat 76, facing forwardly, with the upper portion of his legs extending forwardly and in a generally horizontal position to the undersurface over which the device 10 is intended to be ridden. The lower leg, from the knee to the foot, may extend downwardly and at a very slight forward angle. The device is controlled in direct proportion to and as a result of body movements which produce the desired response by being transferred through the seat and chassis to the runner and consequently to the terrain being negotiated. Although steering the device may include tilting same in the direction of the desired turn, steering may also be accomplished by a down and up unweighting, sideslipping, edging and/or use of the side and bottom camber of the runner 12.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A new and improved ski device capable of operation over water, snow, ice, artificial surfaces, or the like. The unit utilizes a seat design articulated to a single runner in a fashion analogous to the spacing of foot bindings in an ordinary ski. The unit features a stremlined chassis, an anti-sway linkage, improved shock-absorbing means, and a pair of auxiliary foot-mountable short skis for stability, control, and added performance. | 1 |
RELATED APPLICATIONS
[0001] This application claims the benefit of our U.S. Provisional Application No. 61/903,790, filed Nov. 13, 2013, and entitled “Skateboard/Longboard Truck With Active Massive Ball Pivot Mechanism,” which is herein incorporated by reference.
FIELD OF THE INVENTION
[0002] The field of the invention is skateboards and longboards, and more particularly, trucks for skateboards and longboards.
BACKGROUND
[0003] Traditional skateboard truck assemblies accomplish the action of turning when the rider shifts his weight on the skateboard deck from neutral to either side of the skateboard's longitudinal axis.
[0004] Consistent with FIG. 1 a complete skateboard assembly consists of two skateboard trucks with four attached wheels that are attached to a skateboard deck. Each skateboard truck comprises a baseplate assembly, which is attached to the deck, and a hanger assembly on which the wheels are hung.
[0005] As a rider leans the skateboard deck from side to side, the axle integral to the skateboard truck hanger assembly is forced to stay parallel to the ground as long as the weight of the rider forces the wheels to remain in contact with ground. Rotation of the skateboard deck around an axis parallel to the longitudinal centerline of the skateboard deck causes the skateboard truck hanger assemblies to rotate—while staying parallel to the ground—about other axes, resulting in a turning action transmitted through the skateboard truck assemblies.
[0006] Furthermore, when the deck of a typical skateboard is rotated, it causes the hanger assembly to rotate about an axis between the center of the extreme end of the pivot and a point in the center of the hanger aperture coincident with the longitudinal centerline of the kingpin. This causes fore and aft movement of the hanger and the wheels attached to it relative to the neutral position of the trucks when the deck is evenly weighted and parallel to the ground. As the rider angles the deck, the wheels proximate to the weighted side that is angled toward the ground move toward the middle of the skateboard deck, and the wheels on the opposite side from the weighted edge of the deck move away from the middle of the skateboard deck toward the ends of the skateboard deck. The result is that the trucks allow the rider to turn the skateboard by converting the force created by the leaning of the skateboard deck into a controlled turning action. The turning action is accomplished by the fore and aft movement of the wheels attached to the skateboard trucks as they rotate on the kingpin which is oriented at an angle less than 90 degrees to the ground plane ( FIG. 8 ).
SUMMARY
[0007] A skateboard or longboard truck is provided that comprises a hanger and a baseplate assembly. The hanger includes a structural axle-bearing member and a pivot extending out perpendicularly from the structural member, a bushing seat and kingpin aperture located between the structural member and the pivot. The hanger is oriented along a lateral axis and configured to support two wheels. The baseplate assembly has a base that mounts underneath a skateboard or longboard deck. The baseplate assembly also has a mounting flange configured to receive a kingpin to secure the hanger assembly to the baseplate assembly.
[0008] In one aspect of the invention, the hanger is configured with an angle of mechanical advantage of at least twenty degrees, wherein the angle is defined by two lines: the first line runs between a center of the kingpin aperture coincident with a longitudinal center of the kingpin and the pivot's center of rotation, and a second line runs between an outermost contact point of the ball pivot with the pivot cup and an opposing outermost bearing surface of the bushing seat.
[0009] In another aspect of the invention, a kingpin ratio, defined by a distance between a lateral axle centerline perpendicular to the kingpin and a kingpin longitudinal centerline, divided by a distance between a pivot center and the kingpin longitudinal center line, expressed as a percentage, is more than fifty-two percent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The benefits, features, and advantages of the present invention will become better understood with regard to the following description, and accompanying drawings where:
[0011] FIG. 1 is a perspective view of a complete skateboard or longboard assembly
[0012] FIG. 2 is a perspective view of one embodiment of a skateboard or longboard truck according to the present invention.
[0013] FIG. 3 is an exploded perspective view of one embodiment of a skateboard or longboard truck according to the present invention.
[0014] FIG. 4 is a perspective view of a hanger assembly of the truck of FIG. 2 .
[0015] FIG. 5 is a perspective view of a baseplate assembly of the truck of FIG. 2 ,
[0016] FIG. 6 is a top view of the hanger assembly of the skateboard truck assembly of FIG. 2 , illustrating dimensions that factor into the kingpin ratio, the angle of mechanical advantage, and center of pressure.
[0017] FIG. 7 is a side section view of the truck assembly of FIG. 2 , which illustrates the kingpin and baseplate angles of the truck, dual axes of rotation, and pivot load transfer.
[0018] FIG. 8 is a bottom view of the skateboard assembly of FIG. 1 , illustrating the relation between deck angle and truck turning angle.
[0019] FIG. 9 is a perspective view of the pivot cup of FIG. 3 ,
[0020] FIG. 10 is top view of the pivot cup of FIG. 3 , illustration the airgap.
[0021] FIG. 11 is a perspective cut-away view of the pivot cup of FIGS. 3 and 10 , illustrating the threaded airgap and cleaning grooves
[0022] FIG. 12 is a side view of the pivot cup of FIGS. 3 , 10 , and 11 , showing the tolerance fin.
[0023] FIG. 13 is a perspective view of the kingpin of FIG. 3 .
[0024] FIG. 14 is a top view of the kingpin of FIG. 3 , illustrating the tapered section of the shaft.
[0025] FIG. 15A is a view of the hanger assembly of FIG. 3 while articulated, as it would characteristically be if the skateboard or longboard deck were bearing a statically unbalanced load.
[0026] FIG. 15B is a detail view of the ball pivot and pivot cup of FIG. 16A , showing the non-interference zone of the ball pivot and pivot cup.
[0027] FIG. 16A is a top view of a prior art hanger while articulated, as it would characteristically be if a skateboard or longboard deck to which it were coupled were bearing a statically unbalanced load.
[0028] FIG. 16B is a top detail view of the prior art pin pivot and pivot cup of FIG. 16A , illustrating the interference zone of the pin pivot and pivot cup.
[0029] FIG. 17 is a side view of the baseplate of FIG. 3 , showing the tapered walls and kingpin support section.
[0030] FIG. 18 is a sectional view of the hanger assembly along the line 1 - 1 of FIG. 3 in the direction of the arrows, illustrating the bushing seat.
[0031] FIG. 19A is a top view of a prior art skateboard truck assembly with wheels mounted.
[0032] FIG. 19B is a detailed top view of a prior art skateboard truck assembly with wheels mounted showing the need for two axle washers to create the necessary separation between the outer bearing race and face of the structural member.
[0033] FIG. 20A is a top view of the skateboard truck assembly with wheels mounted.
[0034] FIG. 20B is a detailed top view of the skateboard truck assembly with wheels mounted showing that the integral bearing standoffs create the necessary separation between the outer bearing race and face of the structural member.
DETAILED DESCRIPTION
[0035] The following description is presented to enable one of ordinary skill in the art to make and use the present invention as provided within the context of a particular application and its requirements. Various modifications to the preferred embodiment will, however, be apparent to one skilled in the art, and the general principles defined herein may be applied to other embodiments. Therefore, the present invention is not intended to be limited to the particular embodiments shown and described herein, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed.
[0036] The invention relates to a mechanism known in general terms as a skateboard truck. A skateboard truck connects wheels to a skateboard or longboard deck allowing articulation of the wheels attached to the skateboard truck by application of the rider's weight to one side of the deck ( FIG. 8 ). Application of weight to the edge of the skateboard deck allows the skateboard to be turned as the articulation of the deck converts deck angle changes into fore and aft movement of wheels attached to the skateboard truck. The invention improves on prior art in multiple ways, including an improved functional geometry, improved structural design, improved constructability, improved maintainability, and improved durability resulting in smoother and more responsive or immediate turning performance.
[0037] The skateboard truck is comprised of two major assemblies, the ball pivot hanger assembly and the baseplate assembly. The assemblies are mechanically joined together and retained by a kingpin washer, elastomeric bushings, and kingpin nut ( FIG. 1 ).
[0038] The hanger assembly is comprised of the hanger body, axle, axle washers and axle nuts. The body of the hanger incorporates a structural member oriented along a lateral axis perpendicular to and distal from the ball pivot. An axle made of a dissimilar material passes through the beam section of the body parallel to the beam. Alternatively, the axle may be made of two segments that pass into but not through the beam. On each end of the axle or axles there is an axle nut and axle nut washer. The ball pivot may be an integral part of the hanger body or may be a separate attached component. The ball pivot is formed so that it may rotate in a similar sized pivot cup by at least about twenty degrees in any direction without making contact with the pivot cup wall ( FIG. 15 ). The ball pivot has a diameter that is preferably at least 13 mm in diameter. There is an aperture in the hanger assembly body through which a kingpin passes that is located between the axle or axles and the ball pivot. The aperture has two elastomeric bushing seats that are concentric with the aperture and centerline of the kingpin. The bushing seats are located above and below the aperture ( FIG. 3 ).
[0039] The baseplate assembly is comprised of a baseplate body, pivot cup and a tapered kingpin ( FIG. 36 ). The baseplate body has a pivot cup cavity in its forward section into which a removable friction fit pivot cup is installed. There are holes drilled into both sides of the baseplate body that are used to provide a means of attachment for the baseplate to the skateboard deck using fasteners.
[0040] The pivot cup that is installed in the baseplate cavity bore provides a load bearing surface for the hanger assembly ball pivot. The pivot cup is designed to transmit loads from the ball pivot to the side-walls of the baseplate pivot cup cavity. The outside surface of cylindrical section of the pivot cup includes retention fins or rings that provide for a friction fit allowing friction based retention of the pivot cup in the pivot cup cavity. The exterior bottom surface of the pivot cup is angled so that no surface is more than fifty degrees off a line running through the center of the pivot cup hole in the bottom of the pivot cup and the center of the hanger-body bushing aperture. The bottom of the pivot cup is more steeply angled than prior art to allow the cup to compress down and toward the center of the pivot cup cavity in the baseplate. The inside contours of the pivot cup include self-cleaning groves that are designed to remove dirt or debris from the ball pivot when the ball pivot rotates. In the center bottom of the pivot cup there is a hole that provides a void for the pivot cup to compress down and into the bottom of the baseplate pivot cup cavity. The hole in the bottom of the pivot cup is also is designed to collect debris as part of the pivot cup's self-cleaning function and if threaded to provide for a means of threaded mechanical extraction using a threaded shaft or the axle of the hanger assembly.
[0041] There is a kingpin support structure on the rear of the baseplate body that contains a tapered bore-hole into which the tapered kingpin is installed. The kingpin is a separate component that is inserted into the baseplate's tapered kingpin bore hole as part of the overall baseplate assembly. The kingpin has a tapered section proximate to the end of the kingpin where the head is designed to prevent rotation. The section in the middle of the kingpin where elastomeric bushings are later installed is of constant diameter that is smaller than the maximum diameter of the kingpin proximate to the head. The end of the kingpin distal from the head of the kingpin has threads that engage a kingpin nut. The kingpin relies on an enlarging taper proximate to the head of the kingpin that matches the angle of taper found in the kingpin bore hole for its mechanical connection to the baseplate. The taper provides for kingpin retention and load transfer to the baseplate through the sidewalls of the tapered kingpin bore hole. Rotation of the tapered kingpin is prevented by trapping the head of the kingpin on the side of the kingpin bore hole that is distal from the side of the kingpin bore hole that is adjacent to the lower elastomeric bushing bearing surface.
[0042] The ball pivot hanger assembly is installed in the baseplate assembly by first placing the lower elastomeric bushing on the kingpin in contact with the adjoining baseplate bearing surface. The second step is to concurrently insert the ball pivot on the hanger assembly into the baseplate pivot cup while lowering the hanger assembly over the kingpin until the lower bushing seat on the hanger assembly has fully engaged the lower elastomeric bushing. Next, the upper elastomeric bushing is placed over the kingpin and seated into the upper bushing seat of the ball pivot hanger assembly. A bushing washer is placed on top of the upper elastomeric bushing. Finally a kingpin nut is threaded onto the kingpin resulting in compression of the bushing washer and the elastomeric bushings. ( FIG. 1 ).
[0043] When fully assembled, the hanger assembly is sandwiched on both sides of the kingpin aperture by two elastomeric bushings, a kingpin washer and kingpin nut in a manner that allows the rider to adjust the level of pressure on the elastomeric bushings to increase or decrease the level of force required to angle the skateboard deck. The functional assembly traps the ball pivot on the hanger assembly in intimate contact with the pivot cup in the baseplate so that the ball pivot hanger assembly can rotate without interference and transfer loads effectively into the side wall of the baseplate as the mechanism is rotated from side to side ( FIGS. 3 , 38 ).
[0044] The drawings, with the exception of those labeled “prior art,” illustrate an embodiment of a skateboard truck 10 comprising a ball pivot hanger 15 , a baseplate assembly 115 , a pivot cup 155 , a kingpin 210 , bushings 242 and 245 , and various fastening members, including washers 250 , 36 and nuts 255 , 37 .
[0045] Geometry
[0046] The skateboard truck 10 improves upon previous skateboard truck designs by changing the geometry and design of one or more key elements of the skateboard truck 10 . Several of these improvements contribute to a high level of mechanical advantage 295 and improved turning function. These improvements include a larger diameter ball pivot 65 , effective transfer of ball pivot loads 142 into the side of the pivot cup cavity 140 , precision bushing seats 40 , the physical form of the baseplate 115 and the hanger 15 , and a tapered kingpin 210 . The improvements, whether considered singly or more preferably in combination, improve riding performance, mechanical function, durability, constructability and maintainability. It should be understood that the invention encompasses not only the synergistic combination of these various improvements, but also sub-combinations and single ones of these improvements.
[0047] Ball Pivot Hanger
[0048] FIGS. 2-4 , 6 and 20 illustrate one embodiment of a ball pivot hanger 15 . The ball pivot hanger 15 comprises a structural member 20 , an integral axle 30 (or a pair of axles 30 mounted in the ends of the beam 20 ), bushing seats 40 , and a ball pivot 65 . The structural member 20 has a form determined by the principles of a wide flange I-beam. Reliefs 28 strategically reduce the mass and weight of the hanger 15 with minimum impact on the hanger's 15 strength. The structural member 20 is oriented to span the widest direction of the hanger 15 . The integral axle 30 , or axles 30 if separate axles are utilized, optionally made of a dissimilar material, runs from one end of the beam 20 to the other protruding so as to provide a mounting location for skateboard wheels 325 .
[0049] The ball pivot hanger 15 includes two axle bearing spacing steps or bosses 35 (e.g., machined features at opposite distal ends of the structural member 20 ). Each boss 35 creates a separation 31 between the axle bearing surface 32 and the face 33 of the structural member 20 within which the axle 30 is contained so as to provide a bearing standoff that eliminates the need for an axle washer 36 known as a speedring. The boss 35 supports the central race 34 of the bearing and prevents the outer race 39 from making contact with the adjoining structural member 20 . Alternatively, the structural member 20 that embraces the axle 30 (or pair of axles 30 ) includes two bearing standoffs 35 that separate a bearing surface 32 of the structural member 20 from a non-bearing surface of the face 33 of the structural member 20 that embraces the axle 30 . The standoff may also be an additional component that is attached to the structural member 20 or axle 30 .
[0050] Concentric top and bottom bushing seats 40 extend outwardly from a midsection of the structural member 20 and provide a zero tolerance fit for elastomeric bushings 242 , 245 . An aperture 45 formed through the centers of the bushing seats 40 receives a kingpin 210 to mount the hanger 15 , sandwiched between the two elastomeric bushings 242 , 245 to the baseplate 115 . An aperture 45 in the hanger 15 between the ball pivot 65 and the axle 30 allows a kingpin 210 to pass through the hanger 15 to assemble the hanger 15 to the baseplate 115 .
[0051] Ball pivot
[0052] FIG. 15 illustrates one embodiment of a ball pivot 65 incorporated into a hanger 15 . The ball pivot 65 extends perpendicularly out from the midsection of the structural member 20 and axle 30 and is, in one embodiment, preferably cast, forged, or machined as an integral part of the hanger 15 ( FIG. 6 ). The ball pivot 65 located on the hanger 15 differs from other traditional pin pivot or ball designs due to its much larger diameter 75 , preferably at least 13 mm, and resulting larger bearing surface. The ball pivot's 65 larger surface area combined with the pivot cup 155 and baseplate 115 design allow for pivot loads 142 to be transferred into the side wall 147 and tapered cavity walls 145 of the baseplate pivot cup cavity 140 instead of the bottom of the pivot cavity 140 as is typical with prior art ( FIG. 16 ). The design of the ball pivot 65 transfers turning load from the ball pivot 65 to the side wall 160 of the pivot cup 155 at a point much closer to the kingpin 210 compared to the small diameter ball or pin pivots 85 of many other designs, that transfer load from the pivot 85 to or near the bottom 102 of the pivot cup 103 through the end 95 of the pivot 85 distal to the axle. The large diameter ball pivot hanger 15 , pivot cup design 155 , tapered kingpin 210 and baseplate 115 design act synergistically to achieve improved turning performance.
[0053] The ball pivot 65 provides unrestricted movement when compared to prior art pin pivots 85 that are not designed to accommodate significant unrestricted rotation on two planes as the skateboard truck 320 is articulated. The ball pivot 65 provides unrestricted turning action within at least about ten degrees from a neutral center line 300 that passes through the center of rotation 70 and a point 60 coincident with the center of the kingpin aperture 45 and the longitudinal center 212 of the kingpin 210 ( FIGS. 7 , 13 - 14 ). Unrestricted turning action within the non-interference area 80 ( FIG. 15 ) is achieved due to an absence of mechanical interference with the pivot cup side wall 160 or progressive resistance from the compression of an elastomeric pivot cup 100 as is common with prior art designs ( FIG. 16 ). This improvement also eliminates the stress and mechanical wear that takes place with many conventional pin pivot 85 designs when they make physical contact with the wall of the pivot cup or pivot cup cavity. The ball pivot 65 on the hanger 15 in conjunction with the pivot cup 155 is configured to provide constant low-friction intimate contact between the pivot cup 155 and the ball pivot 65 allowing the ball pivot 65 to pass its loads through the sidewalls 160 of the pivot cup 155 and then directly into the side wall 160 of the baseplate pivot cup cavity 140 .
[0054] Pivot Cup
[0055] FIGS. 9-12 illustrate one embodiment of a pivot cup 155 . The pivot cup 155 is installed in the baseplate pivot cup cavity 140 . The pivot cup 155 comprises an internal pivot-bearing surface area 165 defined by curved cylindrical interior sidewalls 160 , a cylindrical outer top surface 162 , a ramped outer bottom surface 170 , cleaning grooves or channels 180 , retention fins or rings 195 , 200 , and a ramping tolerance fin 205 . The pivot cup 155 is formed with a bottom center hole or pocket 185 that is configured to avoid contact with a bottom surface area portion 165 of the ball pivot 65 of at least approximately 0.6 steradians. This causes pivot loads 177 to be transferred into the side wall 147 of the baseplate pivot cup cavity 140 instead of the bottom of the pivot cavity as is typical with prior art ( FIG. 16 ).
[0056] The pivot cup 155 provides a load bearing low friction constant contact transfer surface between the ball pivot 65 and the baseplate pivot cup cavity side wall 147 . The pivot cup 115 may be composed of nylon, POM (acetyl), PU (Polyurethane) or other suitable low friction, bearing surface materials. The cylindrical outer top surface 162 of the pivot cup 155 contains fins or rings 195 , 200 , 205 designed to compensate for dimensional tolerance variations between the pivot cup 155 and the pivot cup cavity 140 . The fins 195 retain the pivot cup 155 in the pivot cup cavity 140 and prevent pivot cup 140 rotation. The pivot cup's outer bottom surface 170 is angled to match the bottom portion 145 of the baseplate pivot cup cavity 140 ( FIG. 7 ). This angle provides a ramping force toward the center of the pivot cup cavity 140 when the pivot cup 155 is pressed into the cavity 140 . The ramping force is present when the truck 10 is in use and loads are applied via the rider's weight through the ball pivot 65 on the hanger 15 . The ramping action is designed to center and compress the pivot cup 155 in the baseplate pivot cup cavity 140 .
[0057] The interior sidewalls 160 of the pivot cup 155 contain grooves or channels 180 designed to provide a self-cleaning action relative to the surface of the ball pivot 65 as it rotates in the pivot cup 155 ( FIG. 10 , 11 ). The pivot cup 155 contains a hole 185 in its center so that as the pivot cup 155 is driven into the pivot cup cavity 140 by the ramping action it can compress without interference inward toward the center of the pivot cup cavity 140 , ensuring intimate contact between the internal pivot-bearing surface area 165 of the pivot cup 155 and the ball pivot 65 . The center hole 185 in the bottom of the pivot cup 155 also serves to provide self-cleaning, debris retention and threaded mechanical extraction functions. The pivot cup's center hole 185 may be threaded, allowing mechanical extraction of the pivot cup 165 from the pivot cup cavity 140 using a threaded rod or hanger axle 30 ( FIG. 4 ). Prior art pivot cups are made of soft elastomeric material and do not incorporate self-cleaning, self-centering, tolerance absorbing components, a provision for mechanical removal using threaded tools, or steep ramping surfaces
[0058] Baseplate
[0059] FIGS. 5 , 7 and 17 illustrate one embodiment of a baseplate 115 . The baseplate 115 comprises a flanged base 116 , a kingpin support structure 224 , and a pivot cup cavity bore 140 . The pivot cup cavity bore 140 , located at a forward section of the baseplate 115 , is drilled at angle parallel to the primary or first axis 300 of rotation of the hanger 15 . The top portion 147 of the pivot cup bore 140 is defined by cylindrically shaped walls. The bottom portion 145 of the pivot cup bore 140 is defined by conically shaped tapered cavity walls angled no more than fifty degrees off of the primary rotational axis 300 . Accordingly, the opening angle 149 formed by the tapered cavity walls is no greater than one hundred degrees. The steep tapering of the cavity walls use the force from the rider's weight that is applied via the ball pivot 65 to drive the pivot cup 155 into the angled bottom portion 145 of the pivot cup cavity bore 140 . The ramped outer bottom surface 170 of the pivot cup 140 is configured with angles that match the angle of the bottom portion 145 of the pivot cavity bore 140 and allows for pivot cup compression into the pivot cup cavity bore 140 . Compression of the pivot cup 155 aids in preserving the constant center of rotation 70 allowed for by the ball pivot 65 .
[0060] Also unlike prior art, on the rear section of the baseplate 115 there is a section of the body through which a tapered borehole 211 provides a support structure for the tapered kingpin 210 . The diameter 214 of the kingpin bore 211 hole proximate to the bolt head 215 is larger than the bore diameter 213 distal to the bolt head 215 ( FIG. 17 ). The lower section 222 of the kingpin support structure 224 includes a channel 218 that is used to prevent rotation of the kingpin's head 215 when the kingpin nut 255 is tightened to adjust bushing 242 , 245 tension. The upper section 223 of the kingpin bore hole 211 is designed to function as a seat for the lower elastomeric bushing 242 . The flanges 116 of the base extend along both sides of the baseplate 115 . The flanges 116 contain holes 117 that provide a means to use fasteners to attach the baseplate 115 to the skateboard deck 330 ( FIG. 5 , 7 , 17 ).
[0061] Kingpin
[0062] FIGS. 3 , 7 , and 13 - 14 illustrate one embodiment of a tapered kingpin assembly 207 . The tapered kingpin assembly 207 comprises a tapered kingpin 210 , a kingpin bushing washer 250 , two elastic bushings 242 , 245 , and a nut 255 . The tapered kingpin 210 , which comprises a head 215 connected to a shaft 220 , is used to connect the hanger 15 to the baseplate 115 . The tapered kingpin 210 is removable with no damage to the baseplate assembly 115 and achieves a zero clearance fit when tightened into a matching tapered baseplate kingpin borehole 211 . When tightened by the compression of the kingpin nut 255 against the kingpin bushing washer 250 and two elastomeric bushings 242 , 245 , the kingpin 210 acts as a rigid and integral component of the baseplate 115 . This increased rigidity of the baseplate 115 and kingpin assembly 207 results in improved turning performance by eliminating rocking or working of the kingpin 210 back and forth in a traditional kingpin borehole.
[0063] Prior art includes two primary styles of kingpins. Kingpins that were intended to be removable were based on a simple bolt design with dimensional tolerances that resulted in movement of the kingpin from side to side in the kingpin baseplate bore hole as the truck was subjected to turning actions. Alternatively kingpins used in some prior art skateboard trucks incorporated barbed or splined driven bolts that were driven into the kingpin borehole. The splined or barbed bolt design was not easily removable and the process of removal and reinstallation would frequently result in damage to the kingpin bore hole that would further allow the kingpin to work back and forth as the deck angle was changed. Both the traditional bolt and barbed or splined prior art kingpin designs resulted in degraded truck performance, constructability and or maintainability.
[0064] The kingpin shaft 220 includes a middle tapered section 225 . The remaining one or more sections of the shaft including the threaded end 240 and the constant diameter, are untapered. The tapered portion 225 of the kingpin 210 is located along a portion of the shaft that, when assembled, makes contact with the tapered baseplate borehole 211 . The tapered portion 225 of the kingpin 210 is distal from the threaded end 240 of the kingpin 210 and proximate to the polygonal head 215 . The diameter 230 of the kingpin 210 gets progressively smaller as one travels the length of the tapered section 225 of the shaft 220 from the top end of the tapered section 225 , proximate to the polygonal head 215 , toward the bottom end of the tapered section 225 , relatively more proximate to the bolt threads 240 . The diameter 227 of the kingpin 210 is constant in the un-tapered sections 227 of the shaft 220 which are not designed to engage the baseplate tapered borehole 211 , including locations where the kingpin 210 passes through the elastomeric bushings 242 , 245 ( FIG. 7 , 13 , 14 ).
[0065] The tapered kingpin 210 can be inserted into the tapered baseplate bore hole 211 until the increasing diameter of tapered kingpin 210 exceeds the matching maximum tapered borehole diameter 213 , 214 . The kingpin 210 seats in the tapered borehole 211 with an intimate, zero clearance fit because the kingpin 210 always tapers to a diameter 230 larger than the largest tapered kingpin bore diameter 213 in the baseplate 115 . The tapered shaft 225 of the kingpin 210 is designed retain the kingpin 210 with the head 215 of the kingpin 210 slightly out of contact with the side of the tapered baseplate borehole 130 that is opposite from the side 241 where the elastomeric bushings 242 , 245 seat ( FIG. 7 , 17 , 13 , 14 ).
[0066] The tapered kingpin 210 and tapered kingpin bore hole 211 provide a precision zero clearance kingpin fit in the baseplate kingpin tapered bore hole 211 while allowing for easy removal without damage to the kingpin 210 or kingpin borehole 211 . Because the kingpin 210 is in intimate contact with the tapered sidewalls 226 of the baseplate 115 , the baseplate 115 and kingpin 210 act as one unit transmitting forces precisely and immediately from the changing deck angle 318 into the truck assembly 10 ( FIG. 7 , 17 , 13 , 14 ).
[0067] Center of Rotation
[0068] The location of the center of rotation 70 of the ball pivot 65 ( FIG. 6 ) is different from prior art. The center of rotation 70 of the ball pivot 65 ( FIG. 6 ), and the center of rotation 95 of a conventional prior art pin pivot 85 , are both herein defined as a point within or upon the surface of the pivot 65 , 80 that translates the least, with respect to the baseplate, as the pivot 65 , 80 rotates within a similarly sized pivot cup 155 . The larger diameter ball pivot 65 combined with the pivot cup 155 and baseplate 115 designs move the center of rotation 70 closer to the center of the kingpin aperture than is found in prior art designs. The center of rotation 70 is in the geometric center of the ball pivot 65 . Prior art designs have pin or ball pivots that are typically less than 13 mm in diameter. The center of rotation 95 for prior art pin or ball pivots is the center of the pivot radius proximate to the end of the pivot. Due to the small pivot diameter and the use flexible low-durometer pivot cups (e.g., below 95 a durometer), these prior art designs transfer load thru the end of the pivot by bearing on the bottom of pivot cup. In most cases the use of a small diameter pivot and an elastomeric pivot cup does not provide for a constant center rotation ( FIG. 6 , 15 , 16 ).
[0069] Center of Pressure
[0070] The center of pressure 83 ( FIG. 6 ) for the ball pivot 65 is the location on the ball pivot's face central to where the greatest load is transmitted through the walls of the pivot cup 155 . As a result of moving the center of rotation 70 of the ball pivot 65 back to a point equidistant from all sides of the ball pivot's 65 rotating sphere, the center of pressure 83 also moves back and to the side of the ball pivot 65 relative to traditional pin pivot or ball pivot designs 65 . When turning the truck 10 , the center of pressure 83 is applied against the side 147 of the pivot cup cavity 140 at a point that is significantly distal from the bottom of the pivot cup cavity 140 . The center of pressure for prior art pin or ball pivots, by contrast, is concentrated proximate to the bottom of the pivot cup cavity.
[0071] Angle of Mechanical Advantage
[0072] Various aspects of the invention contribute to the truck's high and consistent mechanical advantage 295 in translating and amplifying the force a rider exerts on the deck into a force that turns the truck ( FIG. 6 ). One influential contribution to the truck's mechanical advantage is the angle 295 between two lines, referred to herein as the “angle of mechanical advantage.” The first line is the primary rotational axis 300 that runs between the center 60 of the kingpin aperture 45 and the ball pivot's constant center of rotation 70 ( FIG. 7 ). The second line 297 runs between an outermost contact point 298 of the ball pivot 65 with the pivot cup 155 and the opposing outermost bearing surface 299 of the bushing seat 40 that retains the elastomeric bushing 242 , 245 laterally in the hanger 15 . Stated another way, the angle of mechanical advantage 295 is approximately equal to an inverse tangent of the sum of the ball pivot radius and the kingpin bushing radius divided by the ball-pivot-center-to-kingpin-center distance. A higher angle of mechanical advantage 295 , one that is, for example, at least twenty and preferably at least twenty-five degrees, significantly improves the rider's ability to compress the elastomeric bushings 242 , 245 and magnifies the turning action of the truck 10 when compared with prior art designs. Additionally, the higher level of mechanical advantage 295 allows the truck 10 to rotate on two planes concurrently.
[0073] The proximity between the center of rotation 70 of the ball pivot 65 and the center 60 of the kingpin aperture 45 , the diameter 75 of the ball pivot 65 , the diameter 41 of the bushing seat 40 , and the lack of movement achieved by the tapered kingpin 210 all combine to influence the angle of mechanical advantage 295 and the overall effective leverage the rider achieves against the elastomeric bushings 242 , 245 . A high mechanical advantage 295 without pivot cup 155 restriction also facilitates a more dynamic turning response characteristic.
[0074] King Pin Ratio
[0075] Another contribution to the truck's mechanical advantage is the kingpin ratio ( FIG. 6 ). The kingpin ratio 290 is defined by the distance 291 between the kingpin aperture center 60 and longitudinal axle centerline 270 divided by the distance 292 between the ball pivot center 70 , or the constant center of rotation 70 and the kingpin aperture center 60 . The hanger 15 has a kingpin ratio 291 , expressed as a percentage, of fifty-two percent or more.
[0076] A higher percentage kingpin ratio, in addition to a high angle of mechanical advantage, contributes to the truck's greater mechanical advantage relative to prior art designs.
[0077] Concurrent Rotation on Two Axis
[0078] The ball pivot hanger 15 rotates concurrently around two axes 300 , 305 ( FIG. 7 ). The first axis 300 is between the constant center of rotation 70 of the ball pivot 65 and the kingpin aperture center 60 . The second axis 305 is parallel to the longitudinal centerline 212 of the kingpin 210 and runs thru the constant center of rotation 70 of the ball pivot 65 . This second axis 305 allows the hanger 15 to shift from side to side relative to the kingpin 210 while concurrently rotating relative to the first axis 300 with no pivot cup 155 or pivot cup cavity interference 140 . To rotate around the second axis 305 , the bushings 242 , 245 must be compressed parallel to the kingpin bore hole 211 and the hanger bushing seat retention wall 43 . Any change in deck angle results in both a vertical compression and horizontal compression of the bushings relative to the kingpin ( FIG. 7 ).
[0079] Riding benefit of Design
[0080] All of the forces that compress the bushings 242 , 245 and result in the articulation of the hanger 15 are from the rider's weight. All of the rider's weight is supported by the four wheels 325 mounted on the two axles 30 . A larger distance 291 between the axle 30 and kingpin aperture center 210 in relation to the distance 292 from the kingpin aperture center 210 to the constant center of rotation 70 results in greater mechanical advantage. A greater mechanical advantage results in more leverage acting on the bushings 242 , 245 . With more leverage on the bushings 242 , 245 , the rider is able to more effectively rotate the hanger 15 around the first 300 and the second axes 305 . Because of this increased mechanical advantage 295 , the lack of pivot interference with the pivot cup 155 or baseplate pivot cup cavity 140 , and the ability to rotate the hanger 15 concurrently around two axes 300 , 305 , immediate articulation is achieved resulting in improved turning performance.
[0081] Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions and variations are possible and contemplated. Those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the spirit and scope of the invention as defined by the appended claims. | A skateboard or longboard truck comprises a hanger and a baseplate assembly. A redesigned hanger, a large ball pivot, a load-redirecting pivot cup, a tapered kingpin and other improvements give the hanger a high kingpin ratio and a high angle of mechanical advantage, thereby improving the performance and turning characteristics of the truck. | 0 |
FIELD OF THE INVENTION
The present invention relates generally to measuring devices. More particularly, disclosed herein is a tool for measuring the size of a knitting needle and a method for using the same.
BACKGROUND OF THE INVENTION
It has been said that the only time knitting gauge is not important is when the knitter does not care whether the garment fits or how it looks. Gauge, therefore, is normally considered the most important aspect to achieving successful results in a knitting project. It effectively determines the size and fit of the garment or other item being made. Gauge can be defined as the number of stitches per inch, referred to as stitch gauge, or the number of rows per inch, referred to as row gauge. For example, where a person seeks to knit a sweater of 40 inches around with a recommended stitch gauge of 4 stitches per inch but the actual gauge is 4½ stitches per inch, the resulting sweater will be roughly 7 inches too small. To avoid such errors, knitters typically ensure that they are knitting to proper gauge by crafting a representative swatch, also often referred to as a gauge, prior to beginning the actual knitting project.
For each type of stitch, row gauge and stitch gauge are determined primarily by the type of yarn and the knitting needle size, more particularly the knitting needle diameter. A larger needle will produce fewer stitches per inch than a smaller needle. Knitting patterns normally indicate the gauge on which the pattern is based using a specified needle size and a recommended yarn.
It will be appreciated, therefore, that knowing the knitting needle size is critical to achieving proper gauge. While some needles bear markings to indicate their size, many do not. As a result, the knitter is left guessing as to the precise size of the needle. Since many needle sizes differ by just one quarter of a millimeter, even experienced knitters find reliably determining the exact size of an unmarked needle difficult.
The prior art has disclosed a number of needle sizing devices. However, most such devices are disadvantageous for a number of reasons. For example, one common arrangement under the prior art comprises a flat panel with a plurality of sizing apertures formed therein. Such structures are relatively bulky and, therefore, are less than ideal in relation to transport, packing, and storage. Furthermore, with as many as seventeen or more apertures on a single board, the structures can become confusing to the user as he or she seeks to determine which size indication corresponds to which aperture. Even further, many prior art devices enable the user only to determine needle size in one sizing convention, such as US only or metric only, while knitting patterns vary in the referenced sizing convention.
In light of the above, it becomes clear that there is a need for a needle sizing structure that provides a solution to the disadvantages from which the prior art has suffered. It is clearer still that a needle sizing structure that accomplishes the foregoing while providing a number of heretofore unrealized advantages would represent a truly useful advance in the art.
SUMMARY OF THE INVENTION
Advantageously, the present invention is founded on the basic object of providing a knitting needle sizing structure and method that overcomes the disadvantages demonstrated by the prior art while providing a number of further advantages thereover.
A more particular object of embodiments of the invention is to provide a needle sizing structure and method that enable a quick and accurate determination of needle size.
A further object of embodiments of the invention is to provide a needle sizing structure that is compact in size.
In particular embodiments of the invention, a still further object is to provide a needle sizing structure and method that enable needle size determination under multiple sizing conventions.
A related object of embodiments of the invention is to provide a needle sizing structure and method that facilitate a conversion of needle sizes between sizing conventions.
A resultant object of the invention is to provide a needle sizing structure and method that enable a knitter to achieve proper gauge efficiently and effectively.
These and further objects and advantages of embodiments of the invention will become obvious not only to one who reviews the present specification and drawings but also to one who has an opportunity to experience an embodiment of the instant invention for a needle sizing structure and method. It will be appreciated, however, that, although the accomplishment of each of the foregoing objects in a single embodiment of the invention may be possible and indeed preferred, not all embodiments will seek or need to accomplish each and every potential object and advantage. Nonetheless, all such embodiments should be considered within the scope of the present invention.
In carrying forth the aforementioned objects, a basic embodiment of the present invention for a knitting needle sizing structure for enabling a determination of a diametrical size of a knitting needle comprises a plurality of knitting needle sizing wands and a means for retaining the sizing wands. Each of the sizing wands can comprise a sizing member, such as a sizing ring, with a sizing aperture. Each sizing aperture can have a measuring size corresponding to a knitting needle diametrical size. With this, the size of a knitting needle can be determined by a comparison of the diametrical size of the knitting needle relative to the sizing aperture of a sizing member of one of the plurality of knitting needle sizing wands.
Each knitting needle sizing wand can further include a retaining bar with a proximal end and a distal end, and the sizing ring of each knitting needle sizing wand can be coupled to the distal end of the retaining bar. The means for retaining the plurality of knitting needle sizing wands can take the form of a retaining spindle comprising a rod with a first stop member coupled to the first end thereof and a second stop member coupled to the second end thereof. Each knitting needle sizing wand can have a spindle aperture adjacent to the proximal end thereof, and the rod can be received through the spindle aperture of each of the knitting needle sizing wands.
To ensure that the knitting needle sizing wands are securely retained, the first and second stop members can have cross sectional dimensions greater than a diametrical size of the spindle apertures in the retaining bars of the knitting needle sizing wands. One or both stop members can be removably and replaceably coupled to the rod to enable, if necessary, a removal and replacement of one or more knitting needle sizing wands. In any case, the knitting needle sizing structure can additionally incorporate a rigid panel member retained on the rod of the retaining spindle for providing protection to the knitting needle sizing wands and, if desired, for providing identifying information or the like.
The sizing apertures of the knitting needle sizing wands can have unique sizes relative to one another and can progressively vary in size. The sizing apertures can be crafted pursuant to any sizing convention, whether under the US sizing convention, the Metric sizing convention, or any other sizing convention or combination thereof. In one embodiment, seventeen knitting needle sizing wands can be provided with sizing apertures ranging from US needle size 0 to US needle size 17.
To facilitate the determination of needle size, a sizing legend can be associated with each knitting needle sizing wand, such as by being molded, engraved, or otherwise formed on the retaining bar of each sizing wand. In certain embodiments, the sizing legend can be provided under the US sizing convention and in the equivalent size under the Metric sizing convention.
One taking advantage of an embodiment of the knitting needle sizing structure can simply compare the diametrical size of the knitting needle to the sizing aperture of the sizing ring of one or more of the knitting needle sizing wands until a sizing correspondence is found. With that, the user can know that the knitting needle is the size indicated by the sizing legend provided on the knitting needle sizing wand.
It will be appreciated that the foregoing discussion broadly outlines the more important features of the invention to enable a better understanding of the detailed description that follows and to instill a better appreciation of the inventor's contribution to the art. Before any particular embodiment or aspect thereof is explained in detail, it must be made clear that the following details of construction and illustrations of inventive concepts are mere examples of the many possible manifestations of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawing figures:
FIG. 1 is a perspective view of a knitting needle sizing structure according to the present invention;
FIG. 2 is a top plan view of a sizing wand forming a portion of the knitting needle sizing structure of FIG. 1 ;
FIG. 3 is a bottom plan view of the sizing wand of FIG. 2 ;
FIG. 4 is a view in side elevation of a retaining spindle forming a portion of the knitting needle sizing structure of FIG. 1 ;
FIG. 5 is a view in side elevation of a knitting needle sizing structure pursuant to the present invention employed in the measurement of a size of a typical knitting needle;
FIG. 6 is a top plan view of an alternative arrangement for retaining knitting needle sizing wands; and
FIG. 7 is a top plan view of another arrangement for retaining knitting needle sizing wands.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
As is the case with many inventions, the knitting needle sizing structure and method disclosed herein is subject to a wide variety of embodiments. However, to ensure that one skilled in the art will be able to understand and, in appropriate cases, practice the present invention, certain preferred embodiments of the broader invention revealed herein are described below and shown in the accompanying drawing figures.
Looking more particularly to the drawings, an embodiment of a knitting needle sizing structure according to the present invention is indicated generally at 10 in FIG. 1 . There, the knitting needle sizing structure 10 can be seen to incorporate a plurality of knitting needle sizing wands 12 . In the embodiment of FIG. 1 , a spindle 14 acts as a means for retaining the plurality of knitting needle sizing wands 12 . The knitting needle sizing wands 12 can be individually laterally pivotal and possibly rotatable relative to the spindle 14 such that the knitting needle sizing wands 12 can be operated independently.
Also retained relative to the retaining spindle 14 is a panel member 20 . The panel member 20 can be crafted from a rigid material and can provide protection to the knitting needle sizing wands 12 and the knitting needle sizing structure 10 in general. Advantageously, the panel member 20 can additionally be employed to provide identifying information relative to the knitting needle sizing structure 10 itself and, additionally or alternatively, relative to the owner of the knitting needle sizing structure 10 . Such an identifying function can be considered particularly useful where the knitting needle sizing structure 10 is crafted from a precious metal and also where the knitting needle sizing structure 10 has sentimental value or otherwise has particular value to the owner.
The components of the knitting needle sizing structure 10 , including the knitting needle sizing wands 12 , the retaining spindle 14 , and the panel member 20 can be crafted of numerous different materials or combinations of within the scope of the present invention. For example, embodiments of the knitting needle sizing structure 10 can be formed from plastic while other embodiments of the knitting needle sizing structure 10 could be crafted from any one of a variety of metals, including precious metals. Still other embodiments of the knitting needle sizing structure 10 could be formed from wood. As such, it will be clear that knitting needle sizing structures 10 could be created under any appropriate method or combination of methods including molding, carving, stamping, and any other of the many procedures that would be obvious to one skilled in the art after reading this disclosure.
One of the plurality of knitting needle sizing wands 12 is shown detached from the knitting needle sizing structure 10 in general in FIGS. 2 and 3 . More particularly, the knitting needle sizing wand 12 is shown first in top plan view in FIG. 2 and then in an obverse bottom plan view in FIG. 3 . Each knitting needle sizing wand 12 has a retaining bar 24 with a proximal end and a distal end. A sizing ring 22 is fixed relative to the distal end of each retaining bar 24 . Each sizing ring 22 defines a sizing aperture 25 that is substantially round. A spindle aperture 26 is disposed in each retaining bar 24 adjacent to the proximal end thereof. With this, the spindle 14 can pass through the spindle apertures 26 of each of a plurality of knitting needle sizing wands 12 to retain the same in an independently operable manner.
In FIG. 4 , a spindle 14 according to the present invention is shown alone. The spindle 14 has a rod 30 with a first end and a second end. A first stop member 16 is disposed at the first end of the spindle 14 , and a second stop member 18 is disposed at the second end of the spindle 14 . The sizes and shapes of the first and second stop members 16 and 18 certainly could vary. In this exemplary embodiment, the first stop member 16 is generally spherical and is substantially larger in effective diameter than the second stop member 18 , which is generally egg shaped. The larger, spherical first stop member 16 can be used in holding and manipulating the knitting needle sizing structure 10 . Each of the first and second stop members 16 and 18 preferably will have an effective diameter sufficiently larger than the diameters of the spindle apertures 26 of the knitting needle sizing wands 12 thereby to prevent the knitting needle sizing wands 12 from passing beyond either stop member 16 and 18 .
The first and second stop members 16 and 18 could be fixed relative to the rod 30 , such as by adhesive, by a compression fitting, by welding, by being integrally formed therewith, or by any other effective method. Alternatively, either or both stop members 16 or 18 could be removably and replaceably coupled to the rod 30 to enable, by way of example, an addition, subtraction, or removal and replacement of the knitting needle sizing wands 12 . Such a removable and replaceable coupling could be accomplished in any suitable manner. For example, in the embodiment of FIG. 4 , the first stop member 16 is coupled to the rod 30 by a threaded engagement 32 therewith.
Other means for retaining the knitting needle sizing wands 12 are certainly possible within the scope of the present invention. For example, as FIG. 6 shows, the means for retaining the knitting needle sizing wands 12 could take the form of a ring 34 . The ring 34 could be endless. Alternatively, the ring 34 could be coiled, separable, or otherwise provided with a means for enabling the addition and subtraction of knitting needle sizing wands 12 . Another means for retaining the knitting needle sizing wands 12 is shown in FIG. 7 . There, a rectangular structure 36 is provided. Again, the rectangular structure 36 could be solid or it could incorporate a separable portion or any other means for enabling the addition and subtraction of knitting needle sizing wands 12 .
Of course, the means for retaining the knitting needle sizing wands 12 , whether it be a spindle 14 or any other means, could retain substantially any number of knitting needle sizing wands 12 . The sizing apertures 25 and sizing rings 22 of the knitting needle sizing wands 12 can be uniquely sized relative to one another. For example, the sizing apertures 25 and sizing rings 22 can progressively change in size, increasing or decreasing in diameter depending on the order in which they are taken. In one presently preferred embodiment, for example, seventeen knitting needle sizing wands 12 are disposed on the spindle 14 with each knitting needle sizing wand 12 having a uniquely sized sizing aperture 25 defined by the sizing ring 22 thereof. The sizing rings 22 and sizing apertures 25 of the knitting needle sizing wands 12 have apertures ranging from US size 0 to US size 17. The US sizes roughly correspond to metric sizes 2 mm to 12 mm. More particularly, the knitting needle sizing wands 12 can have sizing rings 22 with sizing apertures 25 progressing as set forth in Chart 1: Knitting Convention Size Equivalents.
CHART 1 Knitting Convention Size Equivalents US 0 1 2 3 4 5 6 7 8 9 10 10.5 10.75 11 13 15 17 Metric 2 2.25 2.50 2.75 3 3.25 3.5 3.75 4 4.5 5 5.5 6 6.5 7 7.5 8 9 10 12
Of course, numerous other embodiments with fewer, more, or alternative sizes are possible and within the scope of the present invention. For example, other embodiments could have sizing rings 22 with sizing apertures 25 ranging from US size 000 to US size 50 with intermediate US sizes of 00, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10.5, 10.75, 11, 13, 15, 17, 19 (16 mm), and 35(19 mm).
As FIG. 3 shows, each knitting needle sizing wand 12 can bear a sizing legend 28 . The sizing legend 28 can be disposed substantially anywhere and in any manner on the knitting needle sizing wand 12 . The sizing legend 28 could be molded, engraved, or otherwise created on each knitting needle sizing wand 12 . In the present example, the sizing legend 28 is disposed on the retaining bar 24 of each knitting needle sizing wand 12 by being molded integrally therewith. In each case, the sizing legend 28 is provided in the US sizing convention and in the equivalent size under the Metric sizing convention. Sizes under other sizing conventions could additionally or alternatively be provided within the scope of the invention.
One seeking to determine the size of a knitting needle 100 can employ an embodiment of the present invention for a knitting needle sizing structure 10 as is suggested in FIG. 5 . The knitter could, by way of example, first choose a knitting needle sizing wand 12 with a sizing ring 22 having a sizing aperture 25 that the knitter believes corresponds to the size of the knitting needle 100 . The sizing ring 22 can then be slipped over the tip of the knitting needle 100 , and the knitter can attempt to pass the sizing ring 22 over the body portion of the knitting needle 100 . If the sizing ring 22 does not fit over the body portion of the knitting needle 100 , then the knitter will know to choose a knitting needle sizing wand 12 with a larger sizing ring 22 . If the sizing ring 22 fits over the body portion of the knitting needle 100 but there is a looseness between the sizing ring 22 and the knitting needle 100 , then the knitter will know to choose a knitting needle sizing wand 12 with a smaller sizing ring 22 . If necessary, the knitter can adjust his or her size selection until a knitting needle sizing wand 12 is located that fits over the body portion of the knitting needle 100 with substantially no play between the sizing ring 22 and the knitting needle 100 . The knitting needle sizing wand 12 with such a fit will represent the size of the knitting needle 100 , and the knitter need only read the sizing legend 28 in the appropriate sizing convention.
The knitting needle sizing structure 10 can thus be employed to determine the exact size of a knitting needle 100 that is unmarked or that is marked in a different sizing convention than the knitter wishes to know. The knitting needle sizing structure 10 can be used relative to knitting needles 100 of any material, whether it be metal, wood, bamboo, plastic, or any other material or combination thereof, and relative to substantially any type of knitting needle 100 including straight needles, double point needles, circular needles, and any other needle type that might now exist or hereafter be developed.
With a plurality of exemplary embodiments and details of the present invention for a knitting needle sizing structure and method disclosed, it will be appreciated by one skilled in the art that numerous changes and additions could be made thereto without deviating from the spirit or scope of the invention. This is particularly true when one bears in mind that the presently preferred embodiments merely exemplify the broader invention revealed herein. Accordingly, it will be clear that those with major features of the invention in mind could craft embodiments that incorporate those major features while not incorporating all of the features included in the preferred embodiments.
Therefore, the following claims are intended to define the scope of protection to be afforded to the inventor. Those claims shall be deemed to include equivalent constructions insofar as they do not depart from the spirit and scope of the invention. It must be further noted that a plurality of the following claims may express certain elements as means for performing a specific function, at times without the recital of structure or material. As the law demands, these claims shall be construed to cover not only the corresponding structure and material expressly described in this specification but also all equivalents thereof. | A knitting needle sizing structure and method for determining a diametrical size of a knitting needle with a plurality of knitting needle sizing wands retained by a retaining spindle with a rod with stop members disposed at opposite ends thereof wherein each knitting needle sizing wand has a sizing ring defining a sizing aperture with a measuring size corresponding to a knitting needle diametrical size. The diametrical size of the knitting needle can be determined by comparing the knitting needle diametrical size to the sizing aperture of one or more knitting needle sizing wands. A sizing legend, which can be in the US, Metric, and/or any other sizing convention, can be associated with each knitting needle sizing wand. | 3 |
BACKGROUND
[0001] This invention relates particularly to monitoring a virtual private network.
[0002] LANs (Local Area Networks), Intranets, and other private networks interconnect user computers, file servers, e-mail servers, databases, and other resources. Typically, organizations want to offer remote access to private network resources to traveling employees, employees working at home, and branch offices without compromising the security of the private network.
[0003] Virtual private networks (a.k.a. Extranets) securely stitch together remote private networks and remote computers using a public network such as the Internet as a communication medium. Each private network can connect to the public network via an extranet switch such as the Contivity™ Extranet switch offered by Nortel™ Networks. Extranet switches provide a variety of virtual private network functions such as network packet tunneling and authentication.
[0004] For configuring the functions provided by the switch, Contivity™ switches offer a web-server and web-pages programmed to configure the different virtual private network functions in response to administrator interaction with the web-pages. By using a browser to navigate to each virtual private network switch, one after another, the administrator can configure the tunneling, authentication, packet filtering, and other functions provided by the switch. Management functions provided by the Contivity™ switches are described in greater detail in the New Oak™ Communications Extranet Access Switch Administrator's Guide.
SUMMARY OF THE INVENTION
[0005] In general, in one aspect, the invention features a method of managing a virtual private network that includes receiving information describing at least one virtual private network attribute from multiple computers providing at least one virtual private network function, preparing a report by organizing the received information into a table that lists each of the multiple computers and the corresponding virtual private network attribute received from each of the multiple computers, and displaying the prepared report to a user.
[0006] Embodiments may include one or more of the following. The method may further include transmitting a request for the information. The virtual private network functions may include providing a tunnel and/or authentication. The attribute may include a tunneling characteristic (e.g., tunnel capacity, number of users actually using a tunnel, the protocol used by a tunnel). The method may further include receiving a time interval, and preparing the report based on the received time interval.
[0007] In general, in another aspect, the invention features a method of managing a virtual private network that includes transmitting a request for tunneling data to multiple computers providing virtual private network tunnels, receiving the requested tunneling data from the multiple computers in response to the request, preparing a report based on the received information, the report being organized into a table that lists the different computers and their corresponding tunneling data, and displaying the prepared report to a user.
[0008] In general, in another aspect, the invention features a method of monitoring a virtual private network that includes receiving information from multiple computers providing virtual private network tunnels, the information including a number of tunnels provided by each computer and a number of users configured to use the tunnels, and displaying the received information to a user.
[0009] In general, in another aspect, the invention features a method of monitoring a virtual private network that includes receiving information from multiple computers providing virtual private network tunnels, the information including usage of tunnel protocols over a period of time, is and displaying the received information to a user.
[0010] In general, in another aspect, the invention features a computer program product, disposed on a computer readable medium, for managing a virtual private network. The computer program includes instructions for causing a processor to receive information describing at least one virtual private network attribute from multiple computers providing at least one virtual private network function, prepare a report by organizing the received information into a table that include the at least one virtual private network attribute received from each of the multiple computers, and display the prepared report to a user.
[0011] Advantages may include one or more of the following. The reports describing virtual private network configuration and activity eases administration of different computers providing virtual private network functions. The capacity information enables an administrator to determine whether a particular virtual private network computer can handle tunnel requirements for additional users. The trending information also provides an administrator with a valuable snapshot of the current tunneling activity served by a particular computer.
[0012] Other advantages of the invention will become apparent in view of the following description, including the figures, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] [0013]FIG. 1 is a diagram illustrating bulk configuration of multiple extranet switches.
[0014] [0014]FIG. 2 is a diagram of tunnels provided by configured extranet switches.
[0015] [0015]FIG. 3 is a flow-chart of a process for bulk configuring multiple extranet switches.
[0016] [0016]FIG. 4 is a diagram of a switch manager exporting configuration information to multiple extranet switches.
[0017] FIGS. 5 - 13 are screenshots of a wizard that guides an administrator through a bulk configuration process
[0018] [0018]FIG. 14 is a diagram illustrating importing information from multiple extranet switches.
[0019] [0019]FIG. 15 is a diagram of a switch manager importing information from an extranet switch.
[0020] FIGS. 16 - 20 are screenshots of extranet switch reports.
[0021] FIGS. 21 - 31 are screenshots of a graphical user interface that enables an administrator to manage extranet switches in a virtual private network.
[0022] [0022]FIG. 32 is a screenshot of a menu of links to web-pages offered by an extranet switch.
[0023] FIGS. 33 - 39 are screenshots of web-pages offered by an extranet switch.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] Introduction
[0025] An extranet switch manager provides administrators with a tool that centralizes management of different extranet switches in a virtual private network. The manager can bulk configure multiple extranet switches, prepare reports describing the extranet switches, provide convenient access to individual switch configuration mechanisms, and provide an intuitive representation of virtual private network elements. The manager offers these capabilities to an administrator via an easy to use graphical user interface (GUI). After an administrator enters IP (Internet Protocol) addresses of extranet switches in a virtual private network, the switch manager can quickly import and export data to both view the current configuration and activity of the switches and quickly alter the configuration of one or more switches.
[0026] Bulk Configuration of Multiple Extranet Switches
[0027] As shown in FIG. 1, a virtual private network 102 can include private networks 106 , 110 and/or remote computers 114 that communicate over a public network 104 . Each private network 106 , 110 can connect to the public network 104 via an extranet switch 100 a , 100 b such as a Contivity™ Extranet Switch offered by Nortel Networks. As shown, each extranet switch 100 a , 100 b has a private interface that communicates with a private network 106 , 110 and a public interface that communicates with the public network 104 . Extranet switches 100 a , 100 b handle virtual private network functions such as network packet tunneling and authentication. The extranet switches 100 a , 100 b can also enforce packet filtering rules, enforce hours of access, and perform other functions that maintain a secure virtual private network. Many of these functions may be included in a firewall or router. Hence, we use the term “extranet switch” to generically refer to a system providing these functions. As shown in FIG. 1, switch manager instructions 116 reside on a remote computer, however, the instructions 116 could reside on any computer able to communicate with the extranet switches 100 a , 100 b.
[0028] Each switch 100 a , 110 b can provide different tunneling protocols (e.g., PPTP (Point-to-Point Tunneling Protocol), L2F (Layer 2 Forwarding), L2TP (Layer 2 Tunnel Protocol), and IPSec (IP Secure)), different encryption schemes, different authentication mechanisms (e.g., internal or external LDAP (Lightweight Directory Access Protocol) and RADIUS (Remote Authentication Dial-In User Service)), and different packet filtering schemes (e.g., filtering based on the direction of communication, the source and/or destination of a packet, and/or the type of TCP (Transfer Control Protocol) connection established). As shown in FIG. 1, switch manager instructions 116 enable an administrator to quickly configure multiple switches 100 a , 100 b to share a set of common characteristics (e.g., the same authentication scheme and the same tunneling protocols) by transmitting the same configuration information 118 a , 118 b to each switch 100 a , 100 b.
[0029] Referring to FIG. 2, after being configured, the virtual private network 102 permits secure communication between private networks 106 , 110 . For example, a computer 112 on a first private network 110 can securely send network packets to a computer 108 on a second private network 106 by tunneling 120 through the public network 104 . An extranet switch 100 a receiving a packet prior to transmission over the public network 104 can provide a tunnel 120 by encrypting and/or encapsulating the network packet. Encryption encodes packet contents to prevent computers on the public network from reading the original contents. Encapsulation generates a new packet addressed to the extranet switch 100 b at the end of the tunnel 120 and includes the original packet as the contents of the new packet. By analogy, encapsulation is like placing a mail envelope in a bigger envelope with a different mail address. Encapsulation prevents computers on the public network 104 from identifying the addresses of private network 106 , 110 resources.
[0030] When the extranet switch 100 b at the end of the tunnel 120 receives a packet, the extranet switch 100 b can decrypt and de-encapsulate the packet for delivery to its destination 108 . The second extranet switch 100 b can also authenticate information received from the first extranet switch 100 b to make sure a would-be intruder is not masquerading as a member of the virtual private network 102 .
[0031] As shown, a switch 100 a can also provide tunnels for a remote user 114 connected to the public network 104 . For example, an employee can access private network 110 resources by connecting to an ISP (Internet Service Provider) and establishing a tunnel 122 with an extranet switch 100 a . Again, the extranet switch 100 a can authenticate the identity of the remote user 114 to prevent unauthorized access to the private network 110 .
[0032] The extranet switch 100 a can also connect tunnels. For example, if so configured, the switch could connect 124 tunnels 120 and 122 to enable the remote user 114 to also access resources on private network 106 via tunnels 122 and 120 .
[0033] Referring to FIG. 3, switch manager instructions 116 receive 126 information specifying the configuration of multiple extranet switches. The bulk configuration information can be specified by a user, provided by a program that automatically configures switches, or copied from configuration information of a previously configured switch. After receiving 126 the configuration information, the switch manager instructions 116 transmit 128 data and/or instructions corresponding to the received configuration information to the extranet switches. Each extranet switch processes 130 a , 130 b the transmitted information to change its configuration in accordance with the transmitted information.
[0034] Referring to FIG. 4, an extranet switch 100 a , 100 b includes software and/or firmware instructions 130 a , 130 b that handle switch functions. Such functions can include authentication 132 a , tunnel management 134 a , packet filtering 136 a , etc. Each switch 100 a , 100 b can also include a script interface 138 a that processes script commands. For example, a script command of “call omSET sing (“trustedFTPenabled” “ENABLED”)” configures the switch to allow processing of FTP (File Transfer Protocol) requests from trusted computers.
[0035] In one implementation, switch manager instructions 116 include instructions for a graphical user interface 144 (GUI), a script interface 140 , and configuration 142 instructions that model the extranet switches and coordinate the exchange of information between the GUI 144 and the script interface 140 . When a user specifies bulk configuration information via the GUI 146 , the script interface 142 produces a script 118 a , 118 b that includes script commands for configuring the switches in accordance with the user specified information. Appendix A includes a sample configuring script. In the implementation described above, the switch manager 116 can export the configuration information 118 a , 118 b to extranet switches by transmitting the information 118 a , 118 b to a pre-determined switch directory via FTP (File Transfer Protocol). The script interface 138 a , 138 b on the switches 100 a , 100 b detect and process the script upon its arrival.
[0036] The exporting technique described above is merely illustrative and a wide variety of other techniques could be used to coordinate communication between a computer executing switch manager instructions 116 and the different extranet switches 100 a , 100 b . For example, the communication need not use FTP nor need the information take the form of a script.
[0037] Referring to FIG. 5, the GUI provides a wizard (e.g., Bulk Configure Extranet Switches) that enables an administrator to bulk configure multiple extranet switches by interacting with a preprogrammed series of dialogs. The dialogs query an administrator for different sets of switch characteristics. The preprogrammed set of dialogs reduces the chances an administrator will forget to configure a particular set of switch characteristics.
[0038] Referring to FIG. 6, after invoking the bulk configuration wizard, an administrator can select one or more extranet switches to bulk configure. The manager will transmit configuration information only to the selected switches.
[0039] Referring to FIG. 7, the wizard permits an administrator to configure the selected switches to provide an account to a particular administrator. Since a single administrator may be in charge of all the switches in a virtual private network, establishment of an identical administrator account on the different switches enables the administrator to quickly login to the different switches using the same id and password.
[0040] Referring to FIG. 8, each switch may be individually configured to have a unique hostname (e.g., “NOC2000”). An administrator can bulk configure different switches to have the same DNS (domain name service) domain such as “myVPN.com”. By defining a common domain for multiple switches, an administrator can thereafter refer to a particular switch by combining the domain name and the hostname (e.g., “myVPN.com/NOC2000”). Primary and backup DNS servers can translate the domain and hostname to a particular IP (Internet Protocol) address. Thus, by specifying a common domain, the administrator can identify a switch by a memorable text entry instead of a more cryptic IP address (e.g., “255.255.68.28”).
[0041] Referring to FIG. 9, an administrator can configure the services offered by the switches. For example, the administrator can enable or disable different tunnel protocols (e.g., IPSec, PPTP, LT2P, and L2F). The GUI also gives the administrator the ability to enable or disable tunneling sessions initiated from within the private network served by a switch and tunneling sessions initiated from a source outside the private network (e.g., “public” tunnels).
[0042] The administrator can also enable or disable different communication protocols such as HTTP (HyperText Transfer Protocol), SNMP (Simple Network Management Protocol), FTP (File Transfer Protocol), and TELNET. Additionally, the manager gives the administrator the ability to control the types of communication allowed. For example, an administrator can enable or disable tunnels between two extranet switches (e.g., branch to branch communication), between two users tunneling to the same switch (e.g., end user to end user), and between a user and a branch office tunneling to the same switch.
[0043] Referring to FIG. 10, an administrator can bulk configure the SNMP traps reported by the switches and the host computers that will receive notification of the traps. SNMP traps allow an administrator to react to events that need attention or that might lead to problems. The switches allow the scripting of SNMP alerts so that a combination of system variables can signal an SNMP trap. The GUI permits the administrator to not only enable or disable different types of traps, but also to provide the interval between execution of the SNMP scripts.
[0044] Referring to FIG. 11, an administrator can also configure RADIUS accounting performed by each selected switch. RADIUS is a distributed security system that uses an authentication server to verify dial-up connection attributes and authenticate connections. RADIUS accounting logs sessions with records containing detailed connection statistics. The administrator can enable and disable RADIUS accounting, configure the switches to use internal or external RADIUS servers, and specify how frequently RADIUS records are stored. By configuring the switches in a virtual private network to use the same RADIUS accounting methods, switch usage and access can be easily compared between the different switches.
[0045] Referring to FIG. 12, if enabled, an administrator can bulk configure the type of RADIUS authentication performed by the switches. For example, as shown, the switches can offer AXENT (AXENT OmniGuard/Defender), SecurID (Security Dynamics SecurID), MS-CHAP (Microsoft Challenge Handshake Authentication Protocol encrypted), CHAP (Challenge Handshake Authentication Protocol), and/or PAP (Password Authentication Protocol) authentication.
[0046] The administrator can also define a primary RADIUS server and one or more alternate servers. The primary server receives all RADIUS authentication inquiries unless it is out of service. In the event that the Primary Server is unreachable, the Switch will query the alternate RADIUS servers. By bulk configuring the servers used to provide RADIUS authentication, administrators can quickly route all RADIUS authentication requests to the same collection of RADIUS servers.
[0047] Referring to FIG. 13, switches may use LDAP authentication in addition to or in lieu of RADIUS authentication. An external LDAP Server such as the Netscape Directory Server can store remote access profiles. The switch queries the LDAP Server for access profile information when a user attempts to establish a tunnel connection. The Master LDAP Server is the primary server to process queries. Should the Master server become unavailable, the switch attempts to initiate a connection with the Slave servers. Bulk configuring different switches to use the same LDAP servers both eases the burden of switch management on the administrator and reduces the likelihood the administrator will inadvertently specify a different LDAP hierarchy on different switches.
[0048] After completing the bulk configuration wizard, the manager stores the specified configuration information, but does not transmit the information until the administrator specifically exports the configuration data. This provides administrators with a safeguard against accidentally bulk configuring the switches with unintended characteristics.
[0049] Reporting Capabilities
[0050] Referring to FIG. 14, in addition to configuring multiple extranet switches 100 a , 100 b , switch manager instructions 116 can also produce reports describing the extranet switches 100 a , 100 b in a virtual private network 102 . As shown, the extranet switches 100 a , 100 b can transmit configuration, capacity, and activity information for inclusion in a report.
[0051] Referring to FIG. 15, switch manager instructions 116 can transmit a script 152 a , 152 b that includes script commands requesting current switch 100 a , 100 b information. For example, a script command of “call omGET using (“security.trustedFTPenabled”)” requests information describing whether an extranet switch 100 a , 100 b is currently configured to accept FTP (File Transfer Protocol) requests from a trusted computer. Appendix B includes a sample script requesting information from a Contivity™ switch.
[0052] The switch 100 a , 100 b script interface 138 a , 138 b processes the script commands 128 and produces a file 150 a , is 150 b including the requested information. The script interface 138 a , 138 b on the switch 100 a , 100 b can store the file in a pre-determined directory. The switch manager instructions 116 can then use FTP to retrieve the information 150 a , 150 b.
[0053] Again, a wide variety of other techniques could enable the switches 100 a , 100 b to communicate with the switch manager instructions 116 . Additionally, instead of the request/response model described above, the switches 100 a , 100 b could schedule periodic execution of a script and/or periodic transmission of the switch information 150 a , 150 b.
[0054] Referring to FIG. 16, the switch manager GUI can provide a menu of different reports that can be produced for selected extranet switches. The manager prepares the report by analyzing and/or including data imported from the different extranet switches.
[0055] Referring to FIG. 17, a first report can display different static attributes of the selected switches such as DNS details.
[0056] Referring to FIG. 18, a security report displays the security configurations of the selected switches such as the enabling/disabling of different tunneling and communication protocols. The security report can also list changes made to the selected switch configurations when such changes occurred (not shown). The report can also include information summarizing failed access attempts to the switches (not shown). This report enables an administrator to quickly view the different security configurations and any troublesome security statistics.
[0057] Referring to FIG. 19, a capacity report shows the current total capacity of tunnels that selected switches can provide and the total number of subscribers and/or users configured to use the switch. This report provides a simple but useful gauge of tunnel capacity. Based on the capacity report, an administrator can decide whether to add more subscribers to an available tunnel pool or to increase the size of tunnel pool, for example, by upgrading or adding an extranet switch.
[0058] Referring to FIG. 20, a trending report displays the number of tunnels for each tunnel technology provided by the different extranet switches over a user-specified amount of time. The report allows subscribers to select any number of currently defined switches or services.
[0059] Custom Views
[0060] Referring to FIG. 21, the switch manager GUI eases administration of a virtual private network extranet switches by collecting information about the entire network in a single display. As shown, the switch manager GUI displays configuration information imported from one or more extranet switches (e.g., via the import mechanism described in conjunction with FIG. 15). The GUI uses a split screen display that includes a navigation pane 200 listing different virtual private network switches 202 , subscribers 204 , and other information such as periodic scheduling 206 of management functions and scripts 208 that can perform these functions. As shown, the listing uses a hierarchical tree to display the virtual private network elements. An administrator can view a listed element in more detail by expanding the tree (e.g., clicking on the “−” or “+” next to an element). The tree display enables an administrator to quickly find, add, remove, and configure different virtual private network extranet switches.
[0061] As shown, the display also provides a tabbed dialog control 210 that provides more information and management options for a virtual private network element currently selected in the navigation pane 200 (e.g., “Configuration Data” 212 ). The control 210 includes dialogs for adding new elements to the tree from a palette 214 of elements, for viewing and altering properties 216 of a selected element, for a list of wizards 218 that perform tasks frequently used with a selected element, and a list of network links 222 that enable an administrator to manually configure an individual extranet switch. By providing management options corresponding to an element selected in the navigation pane 200 , the GUI presents only a relevant subset of a wide variety of different management features at a given moment.
[0062] Referring to FIGS. 22 - 26 , the GUI enables an administrator to quickly view and modify the configuration of any particular switch in the virtual private network from within a single application. For example, as shown, an administrator can quickly add a new subscriber 226 to the virtual private network. Briefly, a subscriber is any entity that uses a virtual private network service (e.g., a tunnel protocol). For example, service providers typically use the same extranet switch to provide virtual private network services to different organizations. In this case, each organization could be considered a subscriber. Subscribers can also be individual users.
[0063] As shown in FIG. 22, after selecting the “Configuration Data” element 212 , a palette tab presents different elements that can be added to the selected virtual private network element 212 . A new subscriber 226 can be added by dragging-and-dropping the subscriber 224 palette tool onto the “Configuration Data” element 212 . As shown in FIG. 23, the administrator can rename the new subscriber 226 . As shown in FIG. 24, by selecting the new subscriber 226 , selecting the “palette” tab 214 , and dragging a “VPN Service” 228 (e.g., a tunnel) from the palette onto the new subscriber 226 , the administrator can also configure a switch or switches to offer a particular tunneling protocol.
[0064] As shown in FIG. 25, the administrator can name the tunnel, define the tunneling technology used by the tunnel (e.g., L2TP), and enter the tunnel starting and ending points which, as shown, are extranet switches.
[0065] As shown in FIG. 26, after configuring different subscribers and switches, the GUI provides an administrator with a variety of different methods of looking at a virtual private network. For example, as shown, by expanding a subscriber 232 an administrator can quickly see shortcuts to the extranet switches 236 , 238 offering tunnels for subscriber use. Alternatively, as shown in FIG. 27, the administrator can view the tunneling technologies offered by a particular switch 240 by using the navigation pane 200 to select the switch's tunnel element 242 . The properties dialog 244 displays the configuration of the different tunneling technologies.
[0066] The different presentations of the data (e.g., subscriber based and switch based) described above enable the administrator to both ensure that subscribers are adequately served and that individual switches are configured as desired.
[0067] Referring to FIGS. 28 - 29 , the process described above (i.e., selecting an element from the tree and using the tabbed dialog to view and modify the element's characteristics) can be used to configure a variety of virtual private network characteristics. For example, by selecting a switch 240 from the navigation pane 200 , the administrator can view and modify the switch's 240 characteristics. As shown in FIG. 28, an administrator can add RADIUS Authentication 244 to a switch 240 by dragging-and-dropping the RADIUS Authentication Server palette selection 242 onto the selected switch 240 . As shown in FIG. 29, the administrator can then set different RADIUS authentication settings for the switch 244 . An administrator can use a similar technique to add and/or configure SNMP (Simple Network Management Protocol) settings, switch interfaces to private and/or public networks, Ethernet settings, IPX (Internetwork Packet Exchange) settings, and other extranet switch features displayed in the switch palette. Appendix C includes screenshots of the different palette elements and their properties that can be used to configure an extranet switch.
[0068] The alterations to the switches, for example, adding RADIUS authentication to a switch, while immediately represented to the administrator, is not exported until explicitly requested by the administrator. Again, this gives the administrator a chance to avoid unintended modifications.
[0069] Referring to FIGS. 30 - 31 , beyond viewing and modifying switch characteristics, an administrator can use the GUI to organize information for easy access and identification of different elements. For example, as shown in FIG. 30, an administrator can drag a folder 250 from the palette onto an element. The administrator can rename the dragged folder 252 (e.g., to “Subscribers”) and drag-and-drop different subscribers into the folder 252 . As shown in FIG. 31, a similar technique enables an administrator to organize different switches into different groupings such as switches using LDAP 254 for authentication and switches using RADIUS 256 .
[0070] Integrated Access to a Switch's Configuration Mechanisms
[0071] As previously described, an extranet switch such as the Contivity™ switch can include a web-server and different network pages (e.g., HTML (HyperText Markup Language) documents) that enable an administrator to individually configure an extranet switch. By navigating to a switch web-server, an administrator can view and/or modify a switch's configuration.
[0072] Referring to FIG. 32, the GUI can present a menu 260 of network links (e.g., link 268 ) to web-pages offered by a selected extranet switch 270 . As shown, the menu 260 includes a description of the link 272 and a corresponding URL (Universal Resource Locator) identifying a web-page offered by a switch. As shown, the URL includes designation of a communication protocol (e.g., HTTP (HyperText Transfer Protocol) 262 , an IP address 264 , and the location of a particular page at the specified IP address 268 . When a user selects a link from the menu 260 , the switch manager can transmit an HTTP request for the selected URL. Alternately, the switch manager can instantiate or call a network browser and pass the selected URL. The GUI prepares each URL in the menu 260 by prepending a switch's IP address 264 to a predefined set of web-page locations 266 .
[0073] By providing the link menu in conjunction with the navigation pane 200 , administrators can quickly access a desired page on any particular switch and can also quickly access the same page (e.g., the users page) on a variety of different switches, one after another. Additionally, the menu 260 obviates the need to remember the different extranet switch URLs or expend the time needed to navigate through any menu provided by the switch itself which necessitates potentially long waits for information to be transmitted to the switch manager.
[0074] As shown, the web-pages include pages that control how a switch handles users (FIG. 33), branch offices (FIG. 34), packet filters (FIG. 35), groups of users (FIG. 36), access hours (FIG. 37), and other information such as a menu that tailors a web-based configuration session (FIG. 39). Descriptions of the functions of these different web-pages is described in the New Oak Communications Extranet Access Switch Administrators Guide, pages 82-138 of which are incorporated by reference herein.
[0075] Other Embodiments
[0076] The embodiments described above should not be considered limiting. For example, one of skill in the art could quickly construct a switch manager that perform the functions described above using different GUI controls or a different arrangement of GUI controls.
[0077] Additionally, the techniques described here are not limited to any particular hardware or software configuration; they may find applicability in any computing or processing environment. The techniques may be implemented in hardware or software, or a combination of the two. Preferably, the techniques are implemented in computer programs executing on programmable computers that each include a processor, a storage medium readable by the processor (including volatile and non-volatile memory and/or storage elements), at least one input device, and one or more output devices. Program code is applied to data entered using the input device to perform the functions described and to generate output information. The output information is applied to one or more output devices.
[0078] Each program is preferably implemented in a high level procedural or object oriented programming language to communicate with a computer system. however, the programs can be implemented in assembly or machine language, if desired. In any case, the language may be a compiled or interpreted language.
[0079] Each such computer program is preferable stored on a storage medium or device (e.g., CD-ROM, hard disk or magnetic diskette) that is readable by a general or special purpose programmable computer for configuring and operating the computer when the storage medium or device is read by the computer to perform the procedures described in this document. The system may also be considered to be implemented as a computer-readable storage medium, configured with a computer program, where the storage medium so configured causes a computer to operate in a specific and predefined manner.
[0080] Other embodiments are within the scope of the following claims. | Managing a virtual private network includes receiving information describing at least one virtual private network attribute from multiple computers providing at least one virtual private network function, preparing a report by organizing the received information into a table that lists each of the multiple computers and the corresponding virtual private network attribute received from each of the multiple computers, and displaying the prepared report to a user. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to data compression, and more particularly to a bit rate control mechanism for digital image and video data compression that estimates the number of bits required to represent a digital image or a video at a particular quality in compressed form or alternatively estimates the quality achievable for a digital image or a video when compressed to a given number of bits, which estimates are used to control the number of bits generated by a video compression system.
Visual information may be represented by digital pictures using a finite amount of digital data for still images, and by a finite data rate for time-varying images. Such data in its uncompressed form contains a considerable amount of superfluous information. Image compression techniques attempt to reduce the superfluous information by minimizing the statistical and subjective redundancies present in digital pictures. Pulse code modulation, predictive coding, transform coding, interpolative/extrapolative coding and motion compensation are some of the tools used in image compression techniques.
A digital video/image compression technique may be either lossy or lossless. The lossy compression techniques introduce an irreversible amount of distortion into the picture data. In these techniques a trade-off is made between the amount of distortion added to the original picture input and the number of bits the compressed picture occupies. A rate controller in a video/image compression system controls the number of bits generated by altering the amount of distortion added to the original input by the compression system. In other words a rate controller in a video/image encoder controls the number of bits needed to represent the compressed image by changing the quality of the decompressed image.
Transform coding techniques take a block of samples as the input, transform this block into a number of transform coefficients, quantize the transform coefficients, and variable or fixed length encode the quantized transform coefficients. The input to the transform coding system may be either the original picture elements (pixels), such as in JPEG and intra-MPEG, or the temporal differential pixels, such as in inter-MPEG. An adaptive still image coding technique using a transform coder with a rate controller is shown in FIG. 1. An input image block is transformed by a discrete cosine transform (DCT) function, quantized and variable length coded (VLC). The rate controller observes R(n-1), the number of bits generated by the previous block, and selects a quantizer scale factor Q(n) for the current block. A still image coding scheme, such as JPEG, may be used on a motion picture, as shown in the simplified block diagram of FIG. 2. In these schemes the rate controller observes R(n-1), the number of bits generated by the previous frame (field), and selects a quantizer scale factor Q(n) for the current frame (field). A simplified block diagram of an MPEG encoder is shown in FIG. 3, where R(n-1) is the typical number of bits generated in the previous macroblock. For JPEG Q(n) is referred to as qfactor or quality factor, and for MPEG it is referred to as mquant.
In all of the schemes shown in FIGS. 1-3 Q(n) is used to scale the step sizes of the quantizers of transform coefficients (quantizer matrices). Increasing Q(n) reduces R(n) and vice versa. Q(n) is selected so that R(n), the number of bits generated with this quantizer scale factor Q(n), is close to the targeted rate for the block, frame or field. Q(n) also is an indication of the quality of the decoded block, frame or field. To perform efficiently, a rate control algorithm requires a good estimate of the rate-quality relationships for the input data, i.e., R(n) vs. Q(n). A good rate controller would come up with a Q(n) that results in a targeted R(n). The targeted R(n) for a block, frame or field could vary with n. For example it might take into account the visual characteristic of the block in question, whether the coding is variable bit rate (VBR) or constant bit rate (CBR). A good rate controller tries to keep the Q(n) smooth over n so that the resulting quality of the decoded picture is smooth as well.
Given actual R(n-1), the actual bits generated for the preceding block number n-1, Chen et al, as described in "Scene Adaptive Coder" from IEEE Trans. Communications Mar. 1984, compute Q(n) in the following manner. A buffer status B(n-1) after coding block n-1 is recursively computed using
B(n-1)=B(n-2)+R(n-1)-R
where R is the average coding rate in bits per block. From the buffer status B(n-1) the quality factor Q(n) is computed through
Q(n)=(1-γ)*φ(B(n-1)/B)+γ*Q(n-1)
where φ{} is an empirically determined normalization factor versus buffer status curve and B is the rate buffer size in bits. This produces a smoothly varying Q(n) depending on γ. γ is taken to be less than unity.
Alternatively the Test Model Editing Committee, International Organisation for Standardisation, Test Model 3(Draft), Dec. 1992 computes Q(n) in a similar way as follows. First the virtual buffer status B(n-1) is computed as above. Then Q(n) is computed through the linear relation
Q(n)=K.sub.R *B(n-1)
where K R is a constant that depends on the targeted average bit rate. This Q(n) may be further scaled based on the visual complexity of the block being coded.
Using these techniques Q(n) could change rapidly, and there is no estimate of the quality achievable for a particular block, frame or field with a given number of bits. What is desired is a rate control mechanism that estimates the quality achievable for a digital image or video when compressed to a given number of bits or alternatively estimates the number of bits required to represent a digital image or video at a particular quality in a compressed form.
SUMMARY OF THE INVENTION
Accordingly the present invention provides a bit rate control mechanism for video data compression that either estimates the number of bits required to represent a digital image or video at a particular quality in a compressed form or estimates the quality achievable for a digital image or video when compressed to a given number of bits. A quantizer for compressing the transform coefficients for a current block of samples of a video signal is controlled by a quality factor that is a function of a bit rate for a prior block of samples of the video signal as determined by a rate controller. In the rate controller a complexity parameter is determined as a function of the prior block of samples including the bit rate. The complexity parameter is then used together with the bit rate to generate the quality factor. The rate controller may also include a scene detector for resetting the rate controller at the beginning of each scene.
The objects, advantages and novel features of the present invention are apparent from the following detailed description when read in light of the appended claims and attached drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a block diagrammatic view of an adaptive still image coding technique with a bit rate controller according to the prior art.
FIG. 2 is a block diagrammatic view of a motion JPEG scheme with bit rate control according to the prior art.
FIG. 3 is a block diagrammatic view of an MPEG encoder with bit rate control according to the prior art.
FIG. 4 is a block diagram view of a bit rate controller according to the present invention.
FIG. 5 is an illustrative view of picture grouping for an overlapping window method of determining quality and targeted number of bits according to the present invention.
FIG. 6 is an illustrative view of picture grouping for a non-overlapping window method of determining quality and targeted number of bits according to the present invention.
FIG. 7 is a graphic diagram view of buffer occupancy projection for constant bit-rate operation according to the present invention.
FIG. 8 is a block diagram view of a complexity pre-processor for determining scene cuts according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The relationship between the quality factor Q of a compressed video and the average bits R generated by a block, frame or field of samples is modeled through
R=α*Q.sup.-β,Q>0,α≧0,β>0
where α gives an indication of the complexity of the block being compressed, which may vary from block to block (frame/field to frame/field), and β, which empirically has significantly less variations, may be treated as a constant. This model is applicable to a number of image and video compression techniques, including JPEG, MPEG and MPEG-2. The quality factor Q may be used to generate the qfactor in JPEG or mquant in MPEG through simple scale and saturation operations.
If α and β for block n equal α(n) and β(n) respectively, the targeted bits R(n) for block n may be achieved by using a quality factor Q(n) given by
Q(n)=(R(n)/α(n)).sup.-1/β(n).
In general α(n) and β(n) are not known in advance, but β(n) may be assumed to be a constant β. Then the quality factor is given by
Q(n)=(R(n)/α(n)).sup.-1/β.
In motion JPEG and all MPEG coding schemes all the pictures in the video are compressed the same way, and only one complexity metric needs to be maintained. An input video signal is input to an MPEG or motion JPEG encoder 12 as shown in FIG. 4 to obtain an actual R(n-1) for the prior frame. The actual R(n-1) is input to a processor 14. The processor 14 has a complexity processor 16 which uses the previous history to estimate α(n):
α(n)=(1-γ)*R(n-1).sup.β +γ*α(n-1)
where γ is the smoothing factor in the estimation of α, R(n-1) is the actual number of bits used for picture n-1. Depending upon the application, a value for γ is selected from the range 0≦γ≦1. If γ=1, α(n) is a constant with respect to n, and if γ=0, α(n) depends only on the preceding block coding results. Once α(n) is estimated, then it is input to a quality processor 18 where the quality factor Q(n) may be computed as above. In MPEG the average rate R is used to obtain Q(n), as well as the targeted R(n) for a particular picture. Q(n) is used to obtain results in actual R(n), which is used for updating α(n). In motion JPEG, as well as in all-I MPEG, targeted R(n) is the same for every picture, i.e., equal to the average required rate R. This R is used to obtain Q(n), which is used to obtain actual R(n) for updating α(n).
In a more general compression of video using MPEG the coded pictures may be categorized into three types: I, B and P. An Intra-coded (I) picture is coded using information only from itself. A Predictive-coded (P) picture is coded using motion compensated prediction from a past reference frame or past reference field. A Bidirectionally-coded (B) picture is coded using motion compensated prediction from a past and/or future reference frame(s). A given picture (field/frame) of video has a different coding complexity depending upon whether it is coded as an I, B or P picture. Therefore three picture complexity measures are used for the video, α I , α B and α P for I, B and P pictures respectively. Upon compressing the picture n-1 with a quality factor Q(n-1), the actural output bits R(n-1) are measured. Then depending upon the coded picture type t(n-1) the corresponding picture complexity is updated:
α.sub.t(n-1) (n)=(1-γ)*R(n-1)*Q.sup.β (n-1)+γ* α.sub.t(n-) (n-1)
The other two picture complexities remain unchanged:
α.sub.S (n)=α.sub.S (n-1),s ε{I, B, P}\t(n-1)
Then the target number of bits R(n) and the quality factor Q(n) for the current picture n may be computed through one of two methods: overlapping window method and non-overlapping window method. In both methods, as usually done in the MPEG world, the assumptions are:
Q.sub.B =K.sub.B *Q.sub.I
Q.sub.P =K.sub.P *Q.sub.I
where K B and K P are known constants, and Q I , Q B and Q P are the quality factors used for I, B and P pictures respectively.
In the overlapping window method, also known as the sliding window method, the stream of pictures (fields/frames) to be compressed, in coding order as opposed to the display order, are blocked into overlapping windows of size N as shown in FIG. 5. In this method pictures 0 through N-1 form the first window (WINDOW 0), pictures 1 through N form the second window (WINDOW 1), etc. After compressing each picture, the window is moved to the right by one picture. If N I , N B and N P represent the number of I, B and P pictures remaining in the current window, then for the overlapping window method
N.sub.I +N.sub.B +N.sub.P ≡N
E(n)TargetedR(n)-ActualR(n)
E(-1)-0
Q.sub.I (n)=((α.sub.I N.sub.I +α.sub.B N.sub.B K.sub.B.sup.-62)/((N.sub.I +N.sub.B +N.sub.P)*R+E(n-1))).sup.1/β
where R is the average coding rate in bits per picture. From Q I values of Q B and Q P may be computed.
Finally the target rate R(n) for the picture n is computed through
TargetedR(n)=α.sub.t(n) *Q.sub.t(n).sup.-β (n)
where t(n) is the coding type of picture n.
In summary the overlapping window method has the following steps:
1. Initialize: E(-1) ←0; select values for α's, β, γ and N; n ←0
2. Before coding picture n
(a) update N I , N.sub. B and N P
(b) compute Q I
(c) compute Q B or Q P if needed
(d) compute the target rate R(n)
3. After coding picture n with a quality factor Q t (n), measure the actual bits generated by picture n
4. Compute E(n)←TargetedR(n)-ActualR(n)
5. Update α's
6. Move the window by one picture, increment n, and go to step 2
In the non-overlapping window method the stream of pictures to be compressed, in coding order rather than display order, is blocked into non-overlapping segments or windows of a preselected size N, as shown in FIG. 6. Each picture belongs to one and only one window. Then pictures 0 through N-1 form the first window, pictures N through 2N-1 form the second window, etc. If WinBits represents the bits available to the remaining pictures in the window and N I , N B and N P represent the number of I, B and P pictures remaining in the current window, then for the non-overlapping windows method
N.sub.I +N.sub.B +N.sub.P ≦N
and Q(n) and R(n) are computed as follows:
1. Initialize: WinBits ←0; select values for α's, β, γ and N; n ←0
2. Beginning of window: WinBits ←WinBits +N*R
3. Before coding picture n
(a) update N I , N B and N P
(b) compute Q I (n)=((α I N I +α B N B K B - β)/WinBits) -1/ β
(c) compute Q B or Q P if needed
(d) compute the target rate R(n)
4. After coding picture n with a quality factor Q t (n), measure the actual bits generated by picture n
5. Update WinBits ←WinBits-ActualR(n)
6. Update α's
In MPEG one of the requirements for generating a correctly coded bitstream is that the Video Buffer Verifier (VBV) is not violated. The VBV is a hypothetical decoder, described in ISO/IEC 13818-2 Annex C, which is conceptually connected to the output of an MPEG encoder. The VBV has an input buffer known as the VBV buffer of size B max bits. The target rate R(n) computed in step 2(d) above in the overlapping window method, or in step 3(d) in the non-overlapping window method, may have to be adjusted so as not to overflow or underflow the VBV buffer. The occupancy of the VBV buffer for a constant bit-rate operation of MPEG is shown in FIG. 7 in idealized form. The VBV buffer occupancy B is updated recursively as follows:
If Ba(n-1) is the buffer occupancy right after decoding picture (n-1),
the buffer occupancy just before decoding picture n, Bb{n}, is given by
Bb(n)=Ba)(n-1)+R
where R is the average bits per picture.
The occupancy Ba(n) just after decoding picture n is given by
Ba(n)=Bb(n)-R(n)
where R(n) is the number of bits used for picture n. The relationship between the number of bits per picture, R(n), and the quality factor Q(n), described above may be used by an MPEG encoder to
1. maintain the constraints imposed by the VBV,
2. keep the VBV buffer occupancy operating point center, i.e., away from being nearly full or empty,
3. enable VBV buffer occupancy terminal conditions to be achieved, and
4. predict and avoid any potential VBV overflow and underflow condition.
To use this VBV based rate control strategy, the encoder keeps track of the following:
1. the current VBV buffer occupancy at picture n in coding order just before it is removed from the VBV buffer, i.e., Bb(n),
2. the number of pictures of each picture type (I, P and B) remaining in the current window,
3. the target VBV buffer occupancy at the end of a window, this occupancy being the VBV buffer occupancy just before the last picture within the window is removed from the VBV buffer, i.e., Bb(n+N I +N P +N B ), and
4. the average number of bits per picture, R, assuming a constant bit rate coding.
The number of available bits to code all pictures remaining in the window, either overlapping or non-overlapping methods, is given by
WinBits=Bb(n)+(N.sub.I +N.sub.P +N.sub.B)*R-Bb(n+N.sub.I +N.sub.P +N.sub.B).
Using the model described above the quality factor Q(n) for the remainder of the window is estimated by
Q.sub.I (n)=((α.sub.I N.sub.I +α.sub.P N.sub.P K.sub.P.sup.-β +α.sub.B N.sub.B K.sub.B.sup.-β)/WinBits).sup.1/β.
Then the target bits for each picture type within the window are given by:
TargetR.sub.I =α.sub.I Q.sub.I.sup.-β,
TargetR.sub.P =α.sub.P K.sub.P.sup.-β Q.sub.P.sup.-β, and
TargetR.sub.B =α.sub.B K.sub.B.sup.-β Q.sub.B.sup.-β.
Using these target sizes for each picture type, simulated VBV buffer occupancy trajectory over the window may be computed, i.e., Bb(n) and Ba(n)'s for all remaining pictures of the window are projected. If the trajectory indicates a VBV buffer overflow or underflow or comes close to causing the overflow or underflow, then the window is shortened such that it ends at the point where the overflow or underflow was indicated. A target VBV buffer occupancy is chosen such that no overflow or underflow occurs. With the shortened window Q I (n) and TargetR's are recomputed. This is shown in FIG. 4 where the quality factor Q(n) is input to a buffer occupancy predictor 3Z to project the Bb's and Ba's, which are then input to a VBV comparator 34.
When a satisfactory VBV buffer occupancy trajectory is obtained, then the current picture is coded. When the coding is completed, the actual size of the picture is then used to update the complexity estimates for the current picture type:
α.sub.t(n-1) (n)=(1-γ)*R(n-1)+γ*α.sub.t(N=31 1) (n-1).
For cases where there is no a priori target VBV buffer occupancy to terminate the window, the size of the window is chosen such that it ends on a "Group of Pictures" boundary. In this case Bb(n+N I +N P +N B ) is chosen to be:
Bb(n+N.sub.I N.sub.P N.sub.B)=0.5*(B.sub.max +TargetR.sub.I).
To compensate for the fact that the α parameter does not adapt in a relatively fast manner at scene changes in the input video, the input video as shown in FIG. 4 also is input to an activity estimator 20. The detected activity is input to comparator 22 to determine whether there has been an abrupt change corresponding to a scene change. The activity estimator 20, as shown in more detail in FIG. 8, measures the activity ζ of the picture to be coded in determining the complexity of the picture being compressed. A picture (field/frame) to be coded is broken into four bands by a subband analyzer 24. The variance of the energy in the low-high (LH) and high-low (HL) bands is determined by appropriate variance computational circuits 26, 28, and the two variances are input to a multiplier 30. The measure of activity ζ is calculated as the energy product in low-high and high-low bands:
ζ=σ.sub.LH.sup.2 *σ.sub.HL.sup.2
Any abrupt changes in ζ from picture to picture indicate a scene change in the video signal. When a scene cut or change is detected, the comparator 22 provides a signal to the processor 14 to flush the old value(s) of α(n) and γ is temporarily made equal to 0, i.e., the system is reset. Other forms of scene cut detections are possible and may be used with the rate control mechanism of the present invention.
Thus the present invention provides a rate control mechanism for video compression that uses a special relationship model between the quality factor and the average bits generated using an indication of complexity of the block being processed. | A bit rate control mechanism for a digital image or video compression system estimates a complexity parameter for a current picture, or block of samples, of a video signal as a function of parameters for a prior picture of the video signal, which parameters include a bit rate. From the complexity parameter a quality factor for the current picture is determined and applied to a quantizer to compress the current picture. A complexity pre-processor may also be used to detect scene changes in the video signal prior to estimating the complexity parameter. If there is a scene change detected, then the rate control mechanism is reset prior to estimating the complexity parameter for the first picture in the new scene. | 7 |
RELATED APPLICATION INFORMATION
this application is a 371 of International Appplication PCT/IN2013/000127 filed 4 Mar. 2013 entitled “Process For Producing Amide Compounds”, which was published in the English language on 6 Sep. 2013, with International Publication Number WO2013/128477 A1 and which claims priority from Indian Patent Application Number 602/DEL/2012 filed 2 Mar. 2012, the consent which is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to a process for producing amide compounds in the presence of a non-precious metal-containing ordered, mesoporous solid catalyst.
More particularly, the present invention relates to an efficient and eco-friendly process for producing amide compounds comprising contacting a primary amine with molecular oxygen-containing gas and ammonia solution in the presence of a non-precious metal-containing ordered, mesoporous solid catalyst.
BACKGROUND OF THE INVENTION
Amides are important class of organic compounds used in the manufacture of drugs, engineering plastics, detergents and lubricants. (Meth)acrylamide and caprolactum are two amide group-containing monomeric compounds of great industrial relevance in the preparation of polymers. Compounds of amides are known to have excellent anthropod-controlling activity and application in the treatment of HIV disease.
Although there have been several methods to prepare amides, their preparation under neutral conditions without generating waste by-products is a challenging task. Amides are mostly prepared by the reaction of amines with activated acid derivatives (acid chlorides and anhydrides) (Chemical Abstracts, Vol. 75, 1971, abstract no. 129306g). This reaction generates equimolar quantity of acid by-product which needs further processing steps to neutralize and separate from the desired amide product. Further, this reaction becomes sluggish and often fails to take place if the amine is deactivated due to presence of electron, withdrawing substituents in it.
Amide compounds have also been produced at an industrial scale by hydrating the corresponding nitrile at high temperatures over a reduced metal catalyst—Raney Ni and Cu, for example. In recent times, nitrile hydratase-containing microorganisms are also being used in their production (U.S. Pat. No. 6,043,061; EP 1,266,962 A2; EP 1,835,033A1).
There have been some reports on the direct synthesis of amides from alcohols and amines in the presence of metal catalysts (Gunanathan et al., Science, Year 2007, Vol. 317, pp. 790 792; S. C. Ghosh and S. H. Hong, Eur. J. Org. Chem. Year 2010, pp. 4266-4270). Primary amines are directly acylated by equimolar amounts of alcohols to produce amides and molecular hydrogen (the only product) in high yields and high turnover numbers. This reaction is catalyzed by a homogeneous catalyst, ruthenium complex based on a dearomatized PNN-type ligand [where PNN is 2-(di-tert-butylphosphinomethyl)-6-(diethylaminomethyl)pyridine]. No base or acid promoters are required. However, there is a requirement of additional reagent alcohol to produce amides.
Oxygenation of amines is an efficient route for amides synthesis. This transformation possibly proceeds by a tandom process of oxidative dehydrogenation of amines to nitriles, followed by hydration to produce corresponding amides. Kim et al (Angew. Chem. Int. Ed., Year 2008, Vol. 47, pp. 9249-9251) reported the application of alumina-supported ruthenium hydroxide for this transformation. Ruthenium, a precious metal, is a less abundant and expensive metal and hence, is not desirable for use. Wang et al. (Chem. Commun., Year 2012, DOI: 10.1039/c2cc17499e) demonstrated the use of manganese oxide octahedral molecular sieves (OMS-2) catalysts for this reaction. Low hydrothermal stability and durability are the issues with this catalyst. Further, OMS-2 is a microporous catalyst with pore size of 4 to 5 Å. Bulkier amines are, therefore, not amenable for transformation to amides over these prior-art catalysts. Water, a by-product generated during the amide formation reaction deactivates and destabilizes the catalyst. Although, 87% yield of benzylaminde is obtained over fresh catalyst in its first, on reuse the yield of amide dropped down to 82% which is a clear indication of less stability of OMS catalysts during long term usage.
In view of importance of amide compounds in industrial applications and drawbacks of prior-art processes which include use of expensive, low abundant metals, mineral acids or bases for rearrangements, low structural stability and microporosity of catalysts, etc., it is desirable to have a more efficient catalyst process.
Metal-containing porous solid catalysts, especially those of mesoporous silicas, silicates, aluminophosphates and silico-aluminophosphates have been known for their catalytic activity in other organic transformations. These catalysts are known for their high thermal, hydrothermal and mechanical stability during their thick porewalls (20-40 Å). The inventors disclose herein a novel invention wherein ordered, mesoporous non-precious metal-containing catalysts are used for the preparation of amides from amines.
OBJECTIVES OF THE INVENTION
The main objective of present invention is to provide an efficient and eco-friendly process for producing amide compounds in the presence of a non-precious metal-containing ordered, mesoporous solid catalyst.
Another object of present invention is to provide a catalytic process for producing amides wherein the catalyst is stable, rugged and reusable for reactions in the presence of water.
Another object of present invention is to provide an acid/acid chloride and aldehyde-free process for the preparation of amide compounds.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides a process for producing amide compounds from a primary amine with more than 95% conversion, wherein said process comprises the steps of:
a. contacting a primary amine, solvent and ammonia solution with a non-precious metal-containing ordered, mesoporous, solid catalyst, wherein the amount of catalyst ranges from 10 to 40% by weight of amine, solvent ranges from 10 to 30 times by weight of said primary amine and ammonia solution ranges from 2 to 10 times by weight of amine; b. pressurizing the reactor with molecular oxygen-containing gas at a pressure of 2 to 6 bar; c. subjecting the reaction mixture obtained in step (b) to a temperature in the range of 100 to 160° C. and for a reaction period of 3 to 8 hrs to obtain said amide compound, and, d. separating the amide compound from the left out ammonia solution, solvent and catalyst.
In one embodiment of the present invention the non-precious metal-containing mesoporous solid catalyst used in step (a) comprises a third-row transition metal selected from manganese, iron, vanadium, chromium and copper and an ordered, mesoporous catalyst selected from the group of mesoporous silicas, silicates, aluminophosphates and silico-aluminophosphate.
In an embodiment of the present invention the ordered, mesoporous catalyst has an average pore size ranging from 25 to 60 Å, pore wall thickness ranging from 40 to 110 Å and specific surface area ranging from 500 to 1000 m 2 /g.
In another embodiment of the present invention molecular oxygen-containing gas used in step (b) is air or pure oxygen.
In another embodiment of the present invention solvent used in step (a) is selected from the group of 1,4-dioxane, tetrahydrofuran and dimethyl sulphoxide.
In yet another embodiment of the present invention conversion of amine is 100%.
In another embodiment of the present invention the selectivity towards amide compounds, preferably amide and imine is greater than 80% by weight.
In another embodiment of the present invention, solid catalyst has an ordered mesoporous structure with an average pore size ranging from 25 to 60 Å, pore wall thickness ranging from 40 to 110 Å and specific surface area ranging from 500 to 1000 m 2 /g.
In yet another embodiment of the present invention, the solid catalyst is stable and reusable.
In still another embodiment of the present invention, the reaction can be conducted in a batch, semi-batch or continuous fixed-bed reaction mode.
In still yet another embodiment, when the process is conducted in a continuous fixed-bed mode the catalyst is shaped into pellets or extrudates and used.
In still another embodiment of the present invention, the process is carried out optionally in the absence of ammonia.
In still another embodiment of the present invention, the process is carried out optionally in the presence of water.
DETAILED DESCRIPTION OF THE INVENTION
In the investigations leading to present invention, it was found that the non-precious metal-containing mesoporous solid catalysts of the present invention are highly efficient and could be easily separated from the products for further reuse. The prior art catalysts are expensive, less abundant or less stable. A highly stable and easily separable catalyst system e.g., the catalyst of the present invention is more advantageous.
The catalyst of the present invention is efficient even at moderate temperature and oxygen pressure. Near complete conversion of amine and high selectivity of amide compound are obtained.
It is a feature of the process of present invention that the catalyst is a solid and the reaction takes place in a heterogeneous condition. The solid catalyst can be easily separated from products by centrifugation-filtration/decantation for further reuse.
It is another feature of the process of present invention that the-process is eco-friendly, economical and generates no waste products unlike in the prior art processes.
It is the unique feature of the catalyst of present invention that they are highly stable in the aqueous medium.
Another unique feature of the present invention is that its mesoporous structure enables easy access of active sites to the reactant molecules and enables high conversions. Further, the diffusion of reactant and product molecules is higher than that of prior-art catalysts.
Yet another unique feature of the present invention is that the catalyst of the present invention is selective for producing amide but not for breakage of C—N bond of amine.
Still another feature is that amide formation occurs even by water instead of ammonia solution.
Still another feature is that amide formation occurs even by water instead of ammonia solution. Metal-containing mesoporous framework structures of the catalysts of present invention are highly active and selective for the transformation of amines to amides at moderate reaction temperature and pressure. They avoid all the drawbacks of the prior-art catalyst processes. The process using them is more efficient, since the catalyst is used in the mesoporous form. The process of the present invention is eco-friendly as it does not generate by-product inorganic salt formed as a consequence of neutralization steps. Further, the process of the present invention is economical as less expensive and durable catalysts are being employed and as it is possible for the catalytic process to be conducted in a continuous-flow mode.
The novelty in the invention arises from the fact that the reaction has been achieved with excellent conversions using non-precious metals on an ordered mesoporous scaffold. The use of non-precious metals will ensure a more cost effective process while the ordered mesoporous scaffold provides an industrially more feasible platform with better diffusion properties and stability. Previous reports have not been able to show a cost-effective, industrially viable and robust system for carrying out the said reaction.
The present invention is illustrated herein below with examples, which are illustrative only and should not be construed to limit the scope of the present invention in any manner.
EXAMPLES
The catalyst was prepared by the known procedure (Journal of Porous Materials, Vol. 18 (Issue No. 3), Year 2010, pp. 369-378)
Example 1
This example illustrates the preparation of manganese containing three-dimensional, cubic, mesoporous silica catalyst Mn-SBA-16 with Si/Mn molar ratio=40. In a typical synthesis of Mn-SBA-16 (Si/Mn=40), 7.4 g of block-copolymer pluronic F127 (EO 106 PO 70 EO 106 , mol. wt. 12600) was dissolved in 2 M HCl solution (68.74 g of 35.4% conc. HCl in 315.6 g of distilled water) at 40° C. After 2 hrs of stirring, 28.34 g of tetraethyl orthosilicate was added drop-wise over 30 min and continued stirring for 4 hrs. Then 0.86 g of manganese nitrate (97%, Mn(NO 3 ) 2 .4H 2 O, mol. wt. 251, Thomas Baker) dissolved in 10 ml of water was added slowly. The stirring was continued for another 20 hrs at 40° C. The gel formed was transferred into a Teflon-lined stainless-steel autoclave. It was heated at 80° C. for 48 hrs. The solid formed was separated by filtration, washed with distilled water (3 L), dried at 100° C. overnight and calcined in air at 550° C. for 8 hrs. Average pore size=21 Å, specific surface area=569 m 2 /g and pore wall thickness=82 Å.
Example 2
This example illustrates the preparation of manganese containing three-dimensional, cubic, mesoporous silica catalyst Mn-SBA-16 with Si/Mn molar ratio=30. In a typical synthesis of Mn-SBA-16 (Si/Mn=30), 7.4 g of block-copolymer pluronic F127 (EO 106 PO 70 EC 106 , mol. wt. 12600) was dissolved in 2M HCl solution (68.74 g of 35.4% conc. HCl in 315.6 g of distilled water) at 40° C. After 2 hrs of stirring, 28.34 g of tetraethyl orthosilicate was added drop-wise over 30 min and continued stirring for 4 hrs. Then 1.15 g of manganese nitrate (97%, Mn(NO 3 ) 2 .4H 2 O, mol. wt. 251, Thomas Baker) dissolved in 10 ml of water was added slowly. The stirring was continued for another 20 h at 40° C. The gel formed was transferred into a Teflon-lined stainless-steel autoclave. It was heated at 80° C. for 48 hrs. The solid formed was separated by filtration, washed with distilled water (3 L), dried at 100° C. overnight and calcined in air at 550° C. for 8 hrs. Average pore size=31 Å, specific surface area=585 m 2 /g and pore wall thickness=85 Å.
Example 3
This example illustrates the preparation of manganese containing three-dimensional, cubic, mesoporous silica catalyst Mn-SBA-16 with Si/Mn molar ratio=20. In a typical synthesis of Mn-SBA-16 (Si/Mn=20), 7.4 g of block-copolymer pluronic F127 (EO 106 PO 70 EO 106 , mol. wt. 12600) was dissolved in 2 M HCl solution (68.74 g of 35.4% conc. HCl in 315.6 g of distilled water) at 40° C. After 2 hrs of stirring, 28.34 g of tetraethyl orthosilicate was added drop-wise over 30 min and continued stirring for 4 hrs. Then 1.72 g of manganese nitrate (97%, Mn(NO 3 ) 2 .4H 2 O, mol. wt. 251, Thomas Baker) dissolved in 10 ml of water was added slowly. The stirring was continued for another 20 hrs at 40° C. The gel formed was transferred into a Teflon-lined stainless-steel autoclave. It was heated at 80° C. for 48 hrs. The solid formed was separated by filtration, washed with distilled water (3 L), dried at 100° C. overnight and calcined in air at 550° C. for 8 hrs. Average pore size=31 Å, specific surface area=625 m 2 /g and pore wall thickness=87 Å.
Example 4
This example illustrates the preparation of manganese containing three-dimensional, cubic, mesoporous silica catalyst Mn-SBA-16 with Si/Mn molar ratio=50. In a typical synthesis of Mn-SBA-16 (Si/Mn=50), 7.4 g of block-copolymer pluronic F127 (EO 106 PO 70 EO 106 , mol. wt. 12600) was dissolved in 2 M HCl solution (68.74 g of 35.4% conc. HCl in 315.6 g of distilled water) at 40° C. After 2 hrs of stirring, 28.34 g of tetraethyl orthosilicate was added drop-wise over 30 min and continued stirring for 4 hrs. Then 0.69 g of manganese nitrate (97%, Mn(NO 3 ) 2.4 H 2 O, mol. wt. 251, Thomas Baker) dissolved in 10 ml of water was added slowly. The stirring was continued for another 20 hrs at 40° C. The gel formed was transferred into a Teflon-lined stainless-steel autoclave. It was heated at 80° C. for 48 hrs. The solid formed was separated by filtration, washed with distilled water (3 L), dried at 100° C. overnight and calcined in air at 550° C. for 8 hrs. Average pore size=34 Å, specific surface area=627 m 2 /g and pore wall thickness=75 Å.
Example 5
This example illustrates the preparation of manganese-containing three-dimensional, mesoporous, hexagonal silica catalyst, Mn-SBA-12 with Si/Mn molar ratio=20. 8 g of Brij-76 was dissolved, in 40 g of distilled water and 160 g of 0.1 M HCl. The mixture was stirred at 40° C. for 2 hrs. 17.6 g of tetraethyl orthosilicate was added to it over 30 min. Then, 1.07 g of manganese nitrate (97%, Mn(NO 3 ) 2 .4H 2 O, mol. wt. 251, Thomas Baker) dissolved in 10 ml of water was added slowly and the stirring was continued for 20 hrs. The gel formed was transferred into a Teflon-lined stainless steel autoclave and heated at 100° C. for 24 hrs. The solid formed was recovered by filtration, washed thoroughly with distilled water (3 L), dried at 100° C. for 12 hrs, and calcined at 550° C. for 8 h in the air. Average pore size=32 Å, specific surface area=969 m 2 /g and pore wall thickness=74 Å.
Example 6
This example illustrates the preparation of iron-containing three-dimensional hexagonal mesoporous silica catayst Fe-SBA-12 with Si/Fe molar ratio=20. In a typical preparation of Fe-SBA-12 (Si/Fe=20), 8 g of Brij-76 was dissolved in 40 g of distilled water and 160 g of 0.1 M HCl. The mixture was stirred at 40° C. for 2 hrs. 17.6 g of tetraethyl orthosilicate was added to it over 30 min. Then, 0.70 g of anhydrous FeCl 3 (96%, mol. wt. 162.21, Merk) dissolved in 10 ml of water was added slowly. The stirring was continued for 20 hrs. The gel formed was transferred into a Teflon-lined stainless steel autoclave and heated at 100° C. for 24 h. The solid formed was recovered by filtration, washed thoroughly with distilled water (3 L), dried at 100° C. for 12 hrs and calcined at 550° C. for 8 hrs in the air. Average pore size=38 Å, specific surface area=982 m 2 /g and pore wall thickness=68 Å.
Example 7
This example describes the preparation of vanadium-containing three-dimensional, hexagonal mesoporous silica catalyst V-SBA-12 with Si/V molar ratio=30. In a typical preparation of V-SBA-12 (Si/V=30), 8 g of Brij-76 was dissolved in 40 g of distilled water and 160 g of 2 M HCl. The mixture was stirred at 40° C. for 2 hrs and 17.6 g tetraethyl orthosilicate was added to it over 30 min. Then, 0.33 g of ammonium metavanadate (NH 4 VO 3 , mol. wt. 116.98, 99%, Thomas Baker) was added to the above gel and stirring was continued for 20 h. The gel formed was transferred into a Teflon-lined stainless steel autoclave and heated at 100° C. for 24 hrs. The solid formed was recovered by filtration, washed thoroughly with distilled water (2-3 L), dried at 100° C. for 12 hrs and calcined at 550° C. for 8 hrs in the air. Average pore size=50 Å, specific surface area=576 m 2 /g and pore wall thickness=61 Å.
Example 8
This example describes the preparation of manganese containing mesoporous silicate catalyst Mn—Al-SBA-16 with (Si+Al)/Mn molar ratio=30 and Si/Al molar ratio=60. The catalyst was prepared in the same manner as reported in Example 2 except that required quantity of sodium aluminate maintaining Si/Al molar ratio as 20 was added along with tetraethyl orthosilicate. Average pore size=32 Å, specific surface area=592 m 2 /g and pore wall thickness=76 Å.
Example 9
This example describes the preparation of benzamide from benzyl amine over the non-precious metal-containing silica catalysts reported in examples 1-8. In a typical reaction, 5 mmol of benzyl amine, 15 mL of 1,4-dioxane and 1 mL of 25% ammonia solution were charged into a stainless-steel pressure reactor. 0.2 g of catalyst was added to it. The reactor was pressurized to 6 bar with air. Temperature of the reactor was raised to 150° C. and the reaction was conducted for 8 hrs while stirring at a speed of 600 revolutions per min. Then, temperature was lowered down to 25° C. and the reactor was depressurized. Catalyst was separated by centrifugation/filtration. Solvent was evaporated and the liquid portion was analyzed by gas chromatography (Varian 3400). Identity of the products was confirmed by comparing with the standard samples.
Catalytic activity data of different metal-containing catalysts in the preparation of amides are listed in Table 1.
TABLE 1
Catalytic activity data of metal-containing solid porous catalysts
Con-
version
Product
S.
of amine
selectivity (mol %)
No.
Catalyst (Reference example )
(mol %)
Imine
Amide
Aldehyde
1
Mn-SBA-16 (Si/Mn = 20) (Eg 3)
100
25.6
68.9
6.4
2
Mn-SBA-16 (Si/Mn = 30) (Eg 2)
100
19.3
78.0
1.7
3
Mn-SBA-16 (Si/Mn = 40) (Eg 1)
100
34.0
51.2
14.9
4
Mn-SBA-16 (Si/Mn = 50) (Eg 4)
100
40.3
44.7
15.0
5
Mn-SBA-12 (Si/Mn = 20) (Eg 5)
100
30.9
62.3
6.8
6
Fe-SBA-12 (Si/Fe = 20) (Eg 6)
100
31.2
56.9
11.9
7
V-SBA-12 (Si/V = 30) (Eg 7)
100
40.9
42.5
16.6
8
Mn—Al-SBA-16 [(Si + Al)/
100
24.5
54.3
9.7
Mn = 30; Si/Al = 60)
(un-
known =
11.5)
Example 10
This example describes the preparation of benzamide from benzyl amine using manganese containing aluminophosphate catalyst (Mn-APO; Al/Mn molar ratio=30) prepared by the method described in a prior art (Logar et al. Microporous Mesoporous Material, Year 2006, Vol. 96, pages 386-395). using Mn(NO 3 ) 2 as Mn source. In a typical reaction, 5 mmol of benzyl amine, 15 mL of tetrahydrofuran and 1 mL of 25% ammonia solution were charged into a stainless-steel pressure reactor. 0.2 g of catalyst was added to it. The reactor was pressurized to 6 bar with air. Temperature of the reactor was raised to 150° C. and the reaction was conducted for 8 hrs while stirring at a speed of 600 revolutions per min. Then, temperature was lowered down to 25° C. and the reactor was depressurized. Catalyst was separated by centrifugation/filtration. Solvent was evaporated and the liquid portion was analyzed by gas chromatography (Variant 3400). Identity of the products was confirmed by comparing with the standard samples. Benzylamine conversion=100 mol % and benzamide selectivity=64 mol % and imine selectivity=21.2 mol %.
Example 11
This example describes the preparation of benzamide from benzyl amine using manganese containing silica aluminophosphate catalyst (Mn-SAPO) prepared by the method described in a prior art (Cheung et al. Microporous Mesoporous Material, Year 2012, Vol. 156, pages 90-96) using Mn(NO 3 ) 2 as Mn source and with Si+Al/Mn molar ratio of 30. In a typical reaction, 5 mmol of benzyl amine, 15 mL of dimethyl sulphoxide and 1 mL of 25% ammonia solution were charged into a stainless-steel pressure reactor. 0.2 g of catalyst was added to it. The reactor was pressurized to 6 bar with oxygen. Temperature of the reactor was raised to 150° C. and the reaction was conducted for 8 hrs while stirring at a speed of 600 revolutions per min. Then, temperature was lowered down to 25° C. and the reactor was depressurized. Catalyst was separated by centrifugation/filtration. Solvent was evaporated and the liquid portion was analyzed by gas chromatography (Varian 3400). Identity of the products was confirmed by comparing with the standard samples. Benzylamine conversion=100 mol %, benzamide selectivity=40.5 mol % and imine selectivity=42.8 mol %).
Example 12
This example describes the preparation of benzamide from benzyl amine over Mn-SBA-16 (Si/Mn=50) catalyst at 130° C. and air pressure of 6 bar. In a typical reaction, 5 mmol of benzyl amine, 15 mL of 1,4-dioxane and 1 mL of 25% ammonia solution were charged into a stainless-steel pressure reactor. 0.2 g of catalyst was added to it. The reactor was pressurized to 6 bar with air. Temperature of the reactor was raised to 130° C and the reaction was conducted for 8 hrs while stirring at a speed of 600 revolutions per min. Then, temperature was lowered down to 25° C. and the reactor was depressurized. Catalyst was separated by centrifugation/filtration. Solvent was evaporated and the liquid portion was analyzed by gas chromatography (Varian 3400). Identity of the products was confirmed by comparing with the standard samples. Benzylamine conversion=90 mol %, benzamide selectivity=73.8 mol %, imine selectivity=14.5 mol % and benzaldehyde=11.7 mol %.
Example 13
This example describes the preparation of benzamide from benzyl amine over Mar SBA-16 (Si/Mn=50) catalyst without using ammonia solution. In a typical reaction, 5 mmol of benzyl amine and 15 mL of 1,4-dioxane were charged into a stainless-steel pressure reactor. 0.2 g of catalyst was added to it. The reactor was pressurized to 6 bar with air. Temperature of the reactor was raised to 150° C. and the reaction was conducted for 8 hrs while stirring at a speed of 600 revolutions per min. Then, temperature was lowered down to 25° C. and the reactor was depressurized. Catalyst was separated by centrifugation/filtration. Solvent was evaporated and the liquid portion was analyzed by gas chromatography (Varian 3400). Identity of the products was confirmed by comparing with the, standard samples. Benzylamine conversion=100 mol %, benzamide selectivity=5.6 mol %. imine selectivity=63.1 mol % and benzaldehyde=31.3 mol %.
Example 14
This example describes the stability and reusability of Mn-SBA-16 (Si/Mn=30) catalyst in the preparation of benzamide from benzyl amine. The catalyst recovered after the catalytic run in Example 9 is washed with methanol, dried at 90° for 4 h and then reused in this experiment. The reaction was conducted in the same manner as described in Example 9 but with the used Mn-SBA-16 (Si/Mn=30) catalyst. This reusability experiment was carried out for three times. 1st Reuse: Benzylamine conversion=100 mol %, benzamide selectivity=78.3 mol %. imine selectivity=19.0 mol % and benzaldehyde=1.7 mol %. 2 nd Reuse: Benzylamine conversion=100 mol %, benzamide selectivity=77.8 mol %. imine selectivity=19.2 mol % and benzaldehyde=2.0 mol%. 3 rd Reuse: Benzylamine conversion=100 mol %, benzamide selectivity=78.0 mol %. imine selectivity=19.1 mol % and benzaldehyde=1.9 mol %.
ADVANTAGES OF THE INVENTION
Advantages of instant invention are as following:
1. Heterogeneous, solid acid catalyst-based process
2. Reusable catalyst process
3. Efficient and eco-friendly process
4. Generates no waste salt by-products.
5. Reaction at moderate conditions and for short periods of time.
6. Applicable to a large number of amines
7. Can be performed in both batch or continuous fixed-bed reaction mode.
8. The novelty in the invention arises from the fact that the reaction has been achieved with excellent conversions using non-precious metals on an ordered mesoporous scaffold. The use of non-precious metals will ensure a more cost effective process while the ordered mesoporous scaffold provides an industrially more feasible platform with better diffusion properties and stability. Previous reports have not been able to show a cost-effective, industrially viable and robust system for carrying out the said reaction. | An efficient and eco-friendly process for producing amide compounds comprising contacting a primary amine with molecular oxygen-containing gas, solvent and ammonia solution in the presence of a non-precious metal-containing ordered, mesoporous solid catalyst is disclosed. | 2 |
FIELD OF THE INVENTION
This invention relates to heat treating furnaces, and in particular to an electric heat treating furnace having a unique combination of novel features that provide significantly improved operating and maintenance characteristics compared to known heat treating furnaces.
BACKGROUND OF THE INVENTION
Many of the known heat treating furnaces have a hot zone with a circular cross section. A circular cross section hot zone, however, unnecessarily limits the maximum size workpiece load that the heat treating furnace can accommodate. During operation of the known heat treating furnaces, workpieces, furnace components, or in the case of a brazing furnace, the brazing alloy, can drop onto the hot zone floor causing damage thereto. Hitherto, the hot zone enclosure had to be removed in entirety from the furnace pressure vessel in order to repair or replace the hot zone floor. Such a laborious process leaves much to be desired.
There are several known designs for electric heating elements and their associated supports used in electric heat treating furnaces. A problem with the known designs is that they are prone to shorting out because the surfaces of the electrically insulated components of the heating element supports are progressively metallized during heat treating cycles.
Many of the known heating element supports include a stand-off or support shaft that threads into the hot zone enclosure. Such a heating element support is subject to distortion and galling from thermal cycling in the furnace. This distortion and galling causes the threaded portion of the stand-off to seize, which makes the heating element support very difficult to remove.
Another drawback of the known heating element supports is that they must be specifically designed for either graphite or metal heating elements. A graphite heating element is significantly thicker than a metal heating element. Furthermore, the known heating element supports must also be uniquely designed to accommodate different types and/or thicknesses of heat shielding or insulation that is used to line the furnace hot zone enclosure. Still further, the known heating element supports provide little, if any, adjustability for controlling the distance of the heating element from the heat shield.
Gas injection nozzles are used in heat treating furnaces to distribute a cooling gas over the workpiece load during the cooling portion of a heat treating cycle. The known designs for gas injection nozzles include a tube having flared ends which is formed of rolled molybdenum sheet metal. Such a design is disclosed in U.S. Pat. No. 4,560,348, assigned to Abar Ipsen Industries, Inc., the assignee of the present application. Another design employs a threaded graphite tube as described in U.S. Pat. No. 4,765,068. The sheet metal tube design can easily become dislodged during operation of the heat treating furnace. Furthermore, such a nozzle becomes brittle after exposure to several heat treating cycles. The threaded graphite tube has limited utility because it can contaminate the workpieces with carbon during some heat treating processes.
In view of the foregoing, it would be very desirable to have an electric heat treating furnace which overcomes the disadvantages of the known heat treating furnaces.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention there is provided a heat treating furnace, preferably a vacuum heat treating furnace, which includes a pressure vessel, a door disposed at one end thereof for accessing the interior of the pressure vessel, and an enclosure mounted in the pressure vessel and defining a hot zone therein. The hot zone enclosure includes a front wall, a back wall, a pair of sidewalls, a top wall, and a floor and has a substantially rectangular cross section when viewed from the door end of the furnace. The floor is formed separately from the walls and is mounted in the pressure vessel so as to be removable therefrom independently of the hot zone enclosure.
In accordance with another aspect of the present invention there is provided an electric heat treating furnace which includes a novel support for the electric heating elements therein. The electric heat treating furnace also has a hot zone enclosure and the heating element support includes means for mounting the support inside the hot zone on the internal enclosure in such a way that it is not subject to seizing and is, therefore, readily removable after several heat treating cycles. The heating element support also includes a support shaft having a first end attached to the mounting means and a second end extending into the hot zone. An electrically insulated connector is mounted on the second end of the shaft for attachment to the heating element. The insulated connector includes a base portion formed for resisting cracking from thermally induced stress and electrical short circuits that result from metallization. The insulated connector also includes a support portion that extends from the base portion for insertion into an opening in the electric heating element whereby the insulated connector engages with the electric heating element. The heating element support further includes a fastener formed for attaching to the support portion of the insulated connector in order to secure the electric heating element to the insulated connector.
In accordance with a further aspect of the present invention there is provided a heat treating furnace having a novel gas injection nozzle. The gas injection nozzle according to the present invention has a cylindrical wall that defines a gas flow channel having an inlet and an outlet at respective ends of the cylindrical wall. A first flare is formed in the cylindrical wall at the inlet end and a second flare is formed in the cylindrical wall at the outlet end. Together the first and second flares prevent turbulence in the flowing gas. The gas injection nozzle according to the present invention is preferably formed of a ceramic material and includes attachment means formed in the cylindrical wall adjacent the inlet end for attaching the gas injection nozzle in an opening in the hot zone enclosure of the heat treating furnace. In a preferred embodiment the gas injection nozzle of this invention has a collar formed around the circumference of the cylindrical wall between the attachment means and the outlet end for holding the heat shield in place.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing summary as well as the following detailed description of a preferred embodiment of the present invention will be better understood when read in conjunction with the appended drawings in which:
FIG. 1 is a side elevation view of the interior of a heat treating furnace in accordance with the present invention;
FIG. 2 is an end elevation view of the heat treating furnace of FIG. 1 as viewed along line 2--2 of FIG. 1;
FIG. 3 is a side elevation view of the hot zone enclosure of the heat treating furnace of FIG. 2 as viewed along line 3--3 in FIG. 2;
FIG. 4 is an elevation view of the back wall of the heat treating furnace of FIG. 1 as viewed along line 4--4 in FIG. 1;
FIG. 5 is a plan view of the floor of the hot zone of the heat treating furnace of FIG. 1 as viewed along line 5--5 of FIG. 1;
FIG. 6 is a perspective view of an insulating support for an electric heating element used in an electric heat treating furnace according to the present invention;
FIG. 7 is an elevation view in section of the electric heating element support shown in FIG. 6;
FIG. 8 is a partial section view of the heating element shown in FIG. 7 as viewed along line 8--8 in FIG. 7;
FIG. 9 is a perspective view of a gas injection nozzle for a heat treating furnace according to the present invention;
FIG. 10 is a side elevation view of the gas injection nozzle shown in FIG. 9; and
FIG. 11 is a side elevation view in section of the gas injection nozzle of FIG. 10 as viewed along line 11--11 in FIG. 10.
DETAILED DESCRIPTION
Referring now to the drawings wherein like reference numerals refer to the same or similar components across the several views and, in particular, to FIGS. 1 and 2, there is shown an electric heat treating furnace 10 in accordance with the present invention. The electric heat treating furnace 10 includes a pressure vessel 11 having a door 12 at one end thereof. An enclosure 13 mounted inside the pressure vessel 11 defines a hot zone 14 wherein a workpiece load is placed for a heat treating cycle.
The enclosure 13 has a front wall 15, a pair of side walls 16a and 16b, a back wall 17, a top wall 18, and a floor 20. The front wall 15, sidewalls 16a and 16b, back wall 17, and top wall 18 are preferably formed from stainless steel sheet. The walls are covered with a heat insulating shield 22 preferably formed of a graphite composite material.
An electric heating element 24 is disposed inside the hot zone enclosure 13. Preferably, the electric heating element 24 has three sections: a first L-shaped section 24', a second L-shaped section 24", and a bottom section 24'". As shown in FIG. 2, the bottom section 24'" is substantially parallel to the floor 20, whereas the long legs of the L-shaped sections 24' and 24" are substantially parallel to the walls 16a and 16b, respectively.
The electric heating element 24 is supported on the enclosure walls and floor by a plurality of heating element supports 26. The bottom portion 24'" is electrically connected to the L-shaped portions 24' and 24" by means of fasteners 27a and 27b to form a continuous element. In this manner, the bottom portion 24'" of heating element 24 can be disconnected from the L-shaped portions 24' and 24". Electric power terminals 28 are provided to connect the heating element 24 to an external source of electrical energy (not shown).
The arrangement of the side walls 16a and 16b, top wall 18, floor 20, and heating element 24 of the hot zone enclosure 13 provides an opening having a substantially rectangular cross section. Such a configuration can accommodate a workpiece load having a larger cross section than can a known, circular cross section hot zone. In the embodiment shown, the top wall 18 includes angled portions 19a and 19b each of which extends downward at an angle to intersect with the sidewall 16a or 16b. This preferred arrangement provides a hot zone with a polygonal cross section which can accommodate a workpiece load having a higher profile than can a simple rectangular cross section hot zone.
A plurality of gas injection nozzles 30 are mounted in the sidewalls 16a and 16b and the top wall 18 of hot zone enclosure 13. These nozzles 30 direct streams of an inert cooling gas onto a workpiece load during the cooling portion of a heat treating cycle. The cooling gas enters the pressure vessel 11 through a gas intake port 56, flows through the annular region of the pressure vessel 11 outside the hot zone enclosure 13, and into the hot zone 14 through the gas nozzles 30. The cooling gas exits the hot zone 14 through an exhaust duct 46 having a detachable portion 46' and a fixed portion 46". This arrangement obviates the need for a separate plenum surrounding the hot zone enclosure.
The upper assembly of hot zone enclosure 13, which includes the sidewalls 16a and 16b and the top wall 18, is mounted in the pressure vessel 11 by means of hanger support assemblies 32a and 32b suspended from the upper portion of pressure vessel 11. A pair of lower supports 34a and 34b provide additional support and lateral stability for the hot zone enclosure 13 in the pressure vessel 11.
The upper assembly of hot zone enclosure 13 is preferably constructed as a unit which is suspended in the pressure vessel 11 by means of the hanger support assemblies 32a and 32b and the lower supports 34a and 34b. FIG. 3 illustrates the construction of hot zone enclosure 13 as viewed along line 3--3 in FIG. 2. Side wall 16b is fastened to the top wall 18 along the lower edge of angled portion 19b. The upper assembly of enclosure 13 includes a framework for supporting the stainless steel backing members. This framework includes a plurality of vertical support members 62 which are cross-braced with a plurality of horizontal support members 64 near the lower end of sidewall 16b. A series of cross members 66 are fastened to top wall 18 at spaced intervals aligned with the vertical support members 62 to provide rigidity to the stainless steel backing members. Longitudinally oriented stiffening members 68 are also fastened to top wall 18 between the respective cross members 66 for additional rigidity. The framework formed by the respective members 62, 64, 66 and 68, has an inverted U-shape in end aspect. The framework rigidifies the side walls and top wall of the hot zone enclosure 13 so that the upper assembly can be installed in the pressure vessel and removed therefrom as a unit.
The front wall 15 is supported from the door 12 so as to be moveable therewith relative to the hot zone enclosure 13. The back wall 17 is supported in the back end of the pressure vessel 11 independently of the remainder of enclosure 13. As shown in FIG. 4, the back wall 17 is suspended between the hot zone 14 and the fixed portion 46" of the cooling gas exhaust duct 46. FIG. 4 also illustrates the manner in which the heat insulating shield 22 is mounted on back wall 17. A plurality of button-type, hold-down fasteners 45 protrude through the insulating shield and are anchored to the back wall 15 with a threaded stud or a bolt. This method of mounting the heat insulating shield is typical for the other walls and for the floor of enclosure 13.
Referring again to FIGS. 1 and 2, the floor 20 of the hot zone enclosure 13 is constructed separately from the upper portion of hot zone enclosure 13 and is independently supported in the pressure vessel 11 by means of floor supports 36a and 36b mounted on a lower portion of the pressure vessel 11. Because of this arrangement, the floor 20 can be removed independently of the upper portion of hot zone enclosure 13. A set of work-load supports comprising runners 37a, 37b and 37c are mounted in the pressure vessel in a known manner. A plurality of support rods 38 extend from a like plurality of support bases 39 in the floor of the pressure vessel through the hot zone floor 20 to support the runners 37a, 37b and 37c.
Referring now to FIG. 5, there is shown a preferred construction for the floor 20 of the hot zone enclosure 13, in accordance with the present invention. The floor 20 includes a rigid frame 40 constructed of side beams 41 and a plurality of cross beams 42 affixed between the side beams 41 at spaced intervals. A backing member 43 is affixed to the frame 40 in any known manner. The backing member 43 is preferably formed of stainless steel sheet, similar to the side walls and top wall of hot zone enclosure 13. An insulating shield 44 is affixed to the backing member 43 by a plurality of hold down buttons 45.
The detachable portion 46' of exhaust duct 46 is attached to the underside of the floor 20 in a known manner. A plurality of elongated slots 48 are formed through the backing member 43 and insulating shield 44 of floor 20, to provide outlets for the cooling gas from the hot zone 14 to the gas exhaust duct 46. Slot covers 50 are mounted on the work piece support rods 38, a small distance above the surface of floor 20, as shown in FIG. 1, to prevent excess heat radiation from the hot zone and to prevent debris from falling through or blocking the slots 48.
Referring still to FIG. 1, the detachable portion 46' of the exhaust duct 46 has an end which extends beyond the length of floor 20 and which is formed for insertion into an opening 53 in the fixed portion of exhaust duct 52. The opening 53 is shown more clearly in FIG. 4. The fixed portion 46" of the gas exhaust duct 46 communicates with an exhaust port 54 formed in the back end of pressure vessel 11.
Referring now to FIGS. 6 and 7, there is shown a preferred arrangement for a heating element support 26 used in a furnace according to the present invention. A threaded shaft 612 has an insulated connector 614 mounted on one end thereof which is formed to engage with the heating element 24. A first insulated fastener 616 attaches to the insulated connector 614 for securing the electric heating element 24 thereto. It will be appreciated readily that this arrangement permits adjustment to accommodate a wide variety of heating element thicknesses. A second insulated fastener 618 is movably mounted on shaft 612 for retaining the insulating shield 22 in place. It will also be appreciated that this arrangement provides adjustability to accommodate a wide range of shield thicknesses. A locking element 620 is attached to the other end of shaft 612 for removably mounting the support element 26 inside the hot zone 14 on a wall of enclosure 13. The insulated connector 614 and the first and second insulated fasteners 616 and 618 are preferably formed of ceramic material. The preferred material for the insulated connector is A9648 alumina and the preferred material for the insulated fasteners is MUL-6 mullite. Ceramic-coated metal parts can also be used. If desired, the fasteners can be formed of a heat resistant metal such as molybdenum.
The insulated connector 614 has a support portion that includes a threaded stud 622 and a neck portion 626. The threaded stud 622 is formed to extend through an opening in the heating element 624. The neck portion 626 provides additional length in the support portion to accommodate a graphite heating element, which is considerably thicker than a metal heating element. The insulated connector 614 also has a base portion that includes a conical portion 628. The conical portion 628 dissipates heat more evenly than other configurations and thus provides excellent resistance to cracking that results from thermally induced stress in the insulated connector 614.
A threaded receptacle 630 is formed in the insulated connector 614 for receiving the end of threaded shaft 612. An exhaust hole 632 is formed through the support portion of insulated connector 614 to facilitate the removal of gases from the interior of insulated connector 614 when a vacuum is drawn in the pressure vessel 11 during a heat treating cycle. An antimetallization cavity 634 is formed in the base portion of insulated connector 614. The antimetallization cavity 634 inhibits metallization of the base portion of insulated connector 614 thereby preventing short circuits and extending the useful life of the insulated connector 614.
Referring now to FIG. 8, in addition to FIGS. 6 and 7, a non-circular shoulder 624 is formed between the neck portion 626 and the threaded shaft 622 of the insulated connector 614. The shape of the shoulder 624 is selected to mate with a similarly shaped opening in the heating element 24. In the embodiment shown, the shoulder 624 is oval in shape. In this manner, rotation of the insulated connector 614 relative to the heating element 24 is restricted. The first insulated fastener 616 includes a cylindrical portion 636 and a conical portion 638. This construction provides good resistance to cracking from thermally induced stress which could damage the fastener during a heat treating cycle. A threaded bore is formed centrally in the insulated fastener 616 for receiving the threaded shaft 622 such that the fastener 616 can be rotated to secure heating element 24 on insulated connector 614. The second insulated fastener 618 is formed identically to the first insulated fastener 616. If desired, metal washers (not shown), preferably of molybdenum, are used with the insulated connector 614 and the fastener 616. The metal washers are disposed between the connector 614 and the fastener 616 on opposite sides of the heating element 24 to prevent slippage and to inhibit galling of the heating element 24.
The locking element 620 is formed of a tubular member 644 having a plurality of internal threads 646 formed therein, at least along a portion of the length of tubular member 644. A pair of L-shaped slots 648 are formed in the end of tubular member 620 away from the internal threads 646. A receptacle 650 which is preferably a second tubular member having an inside diameter dimensioned to receive the locking element 620 has a retaining wire or pin 654 disposed diametrically therethrough. When locking member 620 is inserted into the receptacle 650, the slots 648 engage with the retaining wire 654. When the locking element 620 is rotated about 1/4 turn, the locking element 620 becomes restrained against removal from the receptacle 650. The receptacle 650 is affixed in an opening in a wall of the hot zone enclosure 13 in a known manner, such as by welding. The shaft 612 and retaining wire 654 are preferably formed of a heat resistant metal such as molybdenum. The locking member 620 and receptacle 650 are preferably formed of a carbon steel or stainless steel.
Referring now to FIGS. 9, 10 and 11, there is shown a preferred embodiment of a gas injection nozzle for use in a heat treating furnace according to the present invention. The gas injection nozzle 30 includes a cylindrical wall 912 which defines a gas flow channel between an inlet 918 and an outlet 920. A first flare 926 is formed in the cylindrical wall 912 at the inlet end and a second flare 930 is formed in the cylindrical wall at the outlet end of nozzle 30. A plurality of course threads 932 are formed in the cylindrical wall adjacent to the inlet end. The threads 932 are preferably as coarse as light-bulb threads and provide a convenient means of attaching the gas injection nozzle 30 in an opening in a wall of the hot zone enclosure 13. Such coarse threading significantly reduces the risk of seizing.
As shown in FIG. 11, the radius of curvature of first flare 926 is substantially shorter compared to the curvature radius of the second flare 930. In the preferred arrangement, the gas flow channel is venturi-like in shape to limit turbulence in and provide substantially laminar flow of the cooling gas through the gas injection nozzle 30.
In the preferred embodiment as shown in FIGS. 9, 10 and 11, the gas injection nozzle 30 also has a collar 914 formed circumferentially about the cylindrical wall 912 intermediate the inlet 918 and outlet 920. Collar 914 functions to retain the heat insulating shield 22 in place. Also in the preferred embodiment shown, the gas injection nozzle 30 has a conical wall portion 916 formed between the collar 914 and the outlet 920. The conical wall portion 916 facilitates formation of the second flare 930 and provides resistance to cracking from thermally induced stress during a heat treating cycle. The gas injection nozzle 30 is preferably formed of a ceramic material, such as MUL-6 mullite. The thickness of the cylindrical wall 912 is selected to provide resistance to cracking from thermally induced stresses.
It will be recognized by those skilled in the art that changes or modifications may be made to the above-described invention without departing from the broad inventive concepts of this invention. It is understood therefore that the invention is not limited to the particular embodiments disclosed herein, but is intended to cover all modifications and changes which are within the scope of the invention as defined in the appended claims. | A heat treating furnace has a hot zone enclosure with a substantially rectangular cross section. The floor of the hot zone enclosure is formed such that it is removable independently of the remainder of the hot zone enclosure. The heat treating furnace has a heating element with a novel support element that is readily mounted on and removed from the hot zone enclosure and which adjusts to accommodate a wide range of heating element thicknesses and insulation shield thicknesses. The electrically insulating components of the support element are formed to resist electrical shorting resulting from metallization and to resist cracking from thermally induced stress. The heat treating furnace further includes a cooling gas injection nozzle formed to reduce turbulence in the injected gas stream and to be readily attached to or removed from the hot zone enclosure. The gas injection nozzle is preferably formed of a ceramic material and is mounted in an opening in the hot zone enclosure by a very coarse, light-bulb-like, thread formed in the body of the gas nozzle. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for actuating active vibration insulators which actively inhibit vibrations of vehicle engines from transmitting.
2. Description of the Related Art
As a conventional method for actuating such active vibration insulators, a highly linear actuator, such as a voice coil motor, for example, has been used to actuate an active vibration insulator with a sine-wave control signal, thereby controlling vibrations with great vibrating forces but with less noises. However, since such a high-performance actuator is highly expensive, it is difficult to use it in vehicles for which it is necessary to inhibit the vibrations of engines from transmitting simply and less expensively.
Moreover, as the other active vibration insulator, an electromagnetic vibrator has been known as disclosed in Japanese Unexamined Patent Publication (KOKAI) No. 2001-117,644, for instance. The conventional electromagnetic actuator comprises an electromagnetic damper, and actuation controlling means. The electromagnetic damper comprises a fastener fitting, a yoke, a rubber elastic member, and a mass member. The fastener fitting is installed to a vehicle, a vibration generating force. The yoke accommodates an electromagnet therein, and is installed to the fastener fitting. The mass member is supported elastically to the yoke by the rubber elastic member. The actuation controlling means inputs electric control signals into the electromagnet of the electromagnetic damper, and lets the electromagnet generate actuating forces having magnitudes which correspond to the magnitudes of the electric control signals. Thus, the conventional electromagnetic actuator actuates the electromagnet to vibrate the mass member, thereby actively inhibiting the vibrations of the vibration generating source from transmitting by means of vibrating forces resulting from the vibrations of the mass member.
The conventional electromagnetic vibrator generates pulsating control signals with respect to rotary pulsating signals which are output from a rotary pulse sensor, for example, and whose frequencies are correlated to the vibration frequencies of the vibration generating source. Moreover, the pulsating control signals are synchronized with the rotary pulsating signals, but simultaneously have phases which are displaced with respect to the phases of the rotary pulsating signals. In addition, the pulsating control signals have control amplitudes which correspond to the vibration amplitudes of the vibration generating source and whose magnitudes are correlated to the magnitudes of duty ratios. Based on the pulsating control signals, the conventional electromagnetic vibrator gives vibrations to the mass member with the actuation controlling means, thereby inhibiting the vehicle from vibrating by means of vibrating forces resulting from the vibrations of the mass member.
However, when an engine is installed to a sub frame of vehicles, the conventional electromagnetic vibrator is installed to the sub frame as well.
Note herein that, when the conventional electromagnetic vibrator turns on or off the pulsating control signals, a secondary or tertiary harmonic signal component arises with respect to a datum frequency in the actuating signals for actuating the electromagnet. Moreover, when the frequency band of the secondary or tertiary harmonic signal component falls around the resonance frequency band of the sub frame, the secondary or tertiary harmonic signal component resonates to a vibration of the sub frame. Here, the phrase, “when the frequency band of the secondary or tertiary harmonic signal component falls around the resonance frequency band of the sub frame,” represents that a fundamental-wave signal component of control frequencies falls in a so-called idling range. That is, there occurs a problem that noises generate because the secondary or tertiary harmonic signal component resonates to a vibration of the sub frame in vehicles under idling. Note, however, that there occurs no such problem in vehicles under running where a fundamental-wave signal component of control frequencies has a high frequency.
SUMMARY OF THE INVENTION
The present invention has been developed in order to solve the aforementioned problems. It is therefore an object of the present invention to provide a method for actuating active vibration insulators, method which can inhibit noises from generating by actuating simple electromagnetic actuators, and which can damp the vibrations of vehicle engines simply and less expensively.
In order to achieve the aforementioned object, a method for actuating active vibration insulators according to the present invention comprises the steps of:
generating an idling control signal in an idling range of a vehicle, the idling control signal produced by adding a higher order harmonic signal component with respect to a control frequency, based on a cyclic pulsating signal emitted from a vehicle engine, to a fundamental-wave signal component of the control frequency; generating a running control signal in a running range of the vehicle, the running control signal composed of the fundamental-wave signal component of the control signal; and actuating an electromagnetic actuator of an active vibration insulator based on one of the idling control signal and the running control signal, thereby inhibiting vibrations of the vehicle engine from transmitting by means of vibrating forces exerted by the electromagnetic actuator.
In the present method arranged as described above, the actuator is actuated based on the idling controlling signal, which is produced by adding the higher order harmonic signal component with respect to the control frequency to the fundamental-wave signal component of the control frequency, in the idling range of the vehicle, a low-frequency vibration range. As a result, not only it is to adequately damp the vibration of the vehicle whose frequency equals the control frequency, but also it is possible to inhibit the higher order harmonic signal component with respect to the control frequency from generating noises.
Moreover, the higher order harmonic signal component can preferably comprise at least one member selected from the group consisting of a secondary harmonic signal component with respect the control signal and a tertiary harmonic signal component with respect thereto. Note herein that the quaternary or more harmonic signal components with respect to the control frequency are less likely to resonate to a vibration of a sub frame of vehicles, because the disadvantageous effect resulting from the quaternary or more harmonic signal components is very minor. On the other hand, the secondary or tertiary harmonic signal component with respect to the control frequency causes the noise problem resulting from the resonance to a vibration of a sub frame of vehicles notably, because the disadvantageous effect resulting from the secondary or tertiary harmonic signal component is greater than the disadvantageous effect resulting from the quaternary or more harmonic signal components relatively. Therefore, when the secondary or tertiary harmonic signal component with respect to the control frequency is added, as the higher harmonic control signal component, to produce the idling control signal, it is possible to securely inhibit noises from generating.
Note that the present method can preferably further comprise a step of:
calculating a set-up frequency from following equation (1):
F s =( NE/ 60)/( N c /k ) (1)
wherein F s specifies the set-up frequency (in Hz); NE specifies engine revolutions per 1 minute (in r/min) and falls in a range of from 1,000 to 1,5000 rpm; N c specifies crankshaft revolutions resulting from ignitions in all engine cylinders (in r); and k specifies the number of engine cylinders (in pieces); wherein the idling range comprises a first vibration range whose frequency is the set-up frequency or less; and the running range comprises a second vibration range whose frequency is higher than the set-up frequency.
Moreover, the running control signal can preferably comprise a rectangle-shaped wave signal which is produced by converting a sine-wave signal of the control frequency into a rectangle-shaped wave.
When actuating the electromagnetic actuator based on the running control signal comprising a rectangle-shaped wave signal, which is produced by converting a sine-wave signal of the control frequency into a rectangle-shaped wave, in the running range of the vehicle, a high-frequency vibration range, the rectangle-shaped wave signal can compensate retarded responses of electromagnetic actuators exhibiting slow response. Accordingly, it is possible to produce sufficiently large vibrating forces. Consequently, it is possible to adequately suppress high-frequency vibrations in the running range. That is, the present method can effectively inhibit vibrations of engines from transmitting while inhibiting noises from generating with less expensive electromagnetic actuators over a wide range of vehicle driving conditions entirely.
Note that a fundamental-wave signal component of the idling control signal can preferably comprise a sine-wave signal of the control frequency, or a rectangle-shaped wave signal which is produced by converting a sine-wave signal of the control frequency into a rectangle-shaped wave. When the primary signal component of the idling control signal comprises a sine-wave signal of the control frequency, it is possible to generate vibrating forces which are adaptable to the vibrations of the vehicle engine. Accordingly, it is possible to appropriately inhibit the vibrations of the vehicle engine from transmitting. On the other hand, when the fundamental-wave signal component of the idling control signal comprises a rectangle-shaped wave signal which is produced by converting a sine-wave signal of the control frequency into a rectangle-shaped wave, it is possible to produce sufficiently large vibrating forces. Consequently, it is possible to securely inhibit the vibrations of the vehicle engine from transmitting. In particular, when a fundamental-wave signal component of the idling control signal comprises a rectangle-shaped wave signal which is produced by converting a sine-wave signal of the control frequency into a rectangle-shaped wave, it is possible to compensate insufficient responses resulting from slow-response electromagnetic actuators. Therefore, it is possible to enhance the vibrating forces exerted by the active vibration insulator.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the present invention and many of its advantages will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings and detailed specification, all of which forms a part of the disclosure.
FIG. 1 is a schematic diagram for roughly illustrating an arrangement of a vibration controller according to an example of the present invention for inhibiting vibrations of a vehicle M's engine from transmitting.
FIG. 2 is a graph,for illustrating a fundamental-wave signal component, a secondary harmonic signal component and a tertiary harmonic signal component which make a control signal according to Example No. 1 of the present invention for a vehicle under idling.
FIG. 3 is a graph for illustrating absolute output computed values produced by synthesizing the fundamental-wave signal component, the secondary harmonic signal component and the tertiary harmonic signal component which make the control signal according to Example No. 1 for the vehicle under idling.
FIG. 4 is a graph for illustrating a fundamental-wave signal component which makes a control signal according to Example No. 1 for a vehicle under running.
FIG. 5 is a graph for illustrating absolute output computed values produced by converting the fundamental-wave signal component into a rectangle-shaped wave signal which makes the control signal according to Example No. 1 for the vehicle under running.
FIG. 6 is a graph for illustrating a fundamental-wave signal component, a secondary harmonic signal component and a tertiary harmonic signal component which make a control signal according to Example No. 2 of the present invention for a vehicle under idling.
FIG. 7 is a graph for illustrating absolute output computed values produced by synthesizing the fundamental-wave signal component, the secondary harmonic signal component and the tertiary harmonic signal component which make the control signal according to Example No. 2 for the vehicle under idling.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Having generally described the present invention, a further understanding can be obtained by reference to the specific preferred embodiments which are provided herein for the purpose of illustration only and not intended to limit the scope of the appended claims.
The present invention will be hereinafter described in detail with reference to specific examples of the present invention using accompanied drawings.
EXAMPLE NO. 1
FIG. 1 roughly illustrates an arrangement of a vibration controller according to Example No. 1 of the present invention by means of a schematic diagram, vibration controller which is for inhibiting vibrations of a vehicle M's engine from transmitting. As illustrated in the drawing, the vibration controller comprises an engine mount 14 , which is provided with an actuator, an active vibration insulator, (hereinafter simply referred to as an “engine mount”), a controller unit 20 , and an actuator 30 . The controller unit 20 generates control signals. The actuator 30 actuates an electromagnetic actuator 15 of the engine mount 14 based on the control signals. Moreover, the vehicle M comprises a vehicle body 10 which is equipped with the engine mount 14 . The engine mount 14 supports an engine 11 , a vibration generating source.
The engine mount 14 comprises a cylinder-shaped housing (not shown), a vibration insulator rubber (not shown) disposed in the cylinder-shaped housing, and the electromagnetic actuator 15 disposed in the cylinder-shaped housing. The electromagnetic actuator 15 can be a solenoid or an electromagnet, for instance, and controls the dynamic displacements of the engine 11 by the displacements of the vibration insulator rubber. The engine mount 14 is fastened to the vehicle body 10 at the lower fastening shaft (not shown), and is installed to the engine 11 at the upper fastening shaft (not shown), thereby supporting the engine 11 . Moreover, a rotary pulse sensor 12 is disposed adjacent to the crankshaft of the engine 11 . The rotary pulse sensor 12 detects engine revolutions, and outputs rotary pulsating signals of the crankshaft to the controller unit 20 .
The controller unit 20 comprises a signal retriever 21 , a frequency judge 22 , a set-up frequency judge/switcher 23 , an idling control signal data storage 24 , an idling control signal computer 25 , a running control signal data storage 26 , and a running control signal computer 27 .
The signal retriever 21 receives rotary pulsating signals S output from the rotary pulse sensor 12 , and retrieves the frequencies of the rotary pulsating signals S and various driving conditions which correlate to the amplitudes and phases of the rotary pulsating signals S. The frequency judge 22 judges whether the frequencies of the rotary pulsating signals S, which the signal retriever 21 retrieves, are a controlled frequency or not. Note that the frequency of the rotary pulsating signals S, which the frequency judge 22 judges to be the controlled frequency, will be hereinafter simply referred to as a“control frequency.” Moreover, the frequency judge 22 outputs the control frequency to the set-up frequency judge/switcher 23 .
The set-up frequency judge/switcher 23 judges whether the control frequency is a set-up frequency F or less, and whether the control frequency is higher than the set-up frequency F s . When the control frequency is the set-up frequency F s or less, the set-up frequency judge/switcher 23 outputs the control frequency to the idling control signal computer 25 . On the other hand, when the control frequency is higher than the set-up frequency F s , the set-up frequency judge/switcher 23 outputs the control frequency to the running control signal computer 27 . That is, the set-up frequency judge/switcher 23 has a function of switching the control signal computation from the idling control signal computer 25 to the running control signal computer 27 or vice versa.
In the vibration controller according to Example No. 1 of the present invention, the set-up frequency F s is calculated by following equation (1).
F s =( NE/ 60)/( N c /k ) (1)
wherein F s specifies the set-up frequency (in Hz); NE specifies engine revolutions per 1 minute (in r/min); N c specifies crankshaft revolutions resulting from ignitions in all engine cylinders (in r); and k specifies the number of engine cylinders (in pieces). Note that the set-up frequency F s , a boundary frequency between the engine 11 's idling range and the engine 11 's running range, lies in a region where “NE,” the engine 11 's revolutions per 1 minute, falls in a range of from 1,000 to 1,500 rpm.
For example, in the case of the 6-cylinder and 4-cycle gasoline engine, a vibration generating source in Example No. 1, the number of engine cylinders k is 6 pieces; and the crankshaft revolutions N c , resulting from ignitions in all engine cylinders, are 2 revolutions. Moreover, when the engine revolutions NE per 1 minute is 1,000 rpm at the boundary between the engine 11 under idling and under running, the set-frequency frequency F s is 50 Hz. In addition, note that the engine revolutions NE and N c are equivalent to the revolutions of the crankshaft, an engine output shaft.
In the vibration controller according to Example No. 1 of the present invention, the set-up frequency judge/switcher 23 outputs the control frequency to the idling control signal computer 25 when the control frequency is 50 Hz or less. On the other hand, the set-up frequency judge/switcher 23 outputs the control frequency to the running control signal computer 27 when the control frequency is higher than 50 Hz.
The idling control signal data storage 24 stores a large number of idling control signal data which correspond to the conditions of the engine 11 under idling. Note that the idling control signal data are prepared in advance based on the frequencies of the rotary pulsating signals S. That is, the idling control signal data storage 24 stores idling control signal data which correspond to the frequencies of the rotary pulsating signals S.
When the set-up frequency judge/switcher 23 inputs the control frequency into the idling control signal computer 25 , the idling control signal computer 25 selects one of the idling control signal data, which correspond to the input control signal, from a large number of the idling control signal data which are stored in the idling control signal data storage 24 . Moreover, the idling control signal computer 25 generates an idling control signal based on one of the selected idling control signal data. That is, the idling control signal computer 25 generates an idling control signal when the control frequency is the set-up frequency F s or less.
The running control signal data storage 26 stores a large number of running control signal data which correspond to the conditions of the engine 11 under running. Note that the running control signal data are prepared in advance based on the frequencies of the rotary pulsating signals S. That is, the running control signal data storage 26 stores running control signal data which correspond to the frequencies of the rotary pulsating signals S.
When the set-up frequency judge/switcher 23 inputs the control frequency into the running control signal computer 27 , the running control signal computer 27 selects one of the running control signal data, which correspond to the input control signal, from a large number of the running control signal data which are stored in the running control signal data storage 26 . Moreover, the running control signal computer 27 generates a running control signal based on one of the selected running control signal data. That is, the running control signal computer 27 generates a running control signal when the control frequency is higher than the set-up frequency F s .
As illustrated in FIG. 1 , the output sides of the idling control signal computer 25 and running control signal computer 27 are connected with the actuator 30 for actuating the electromagnetic actuator 15 of the engine mount 14 , respectively. The actuator 30 turns on or off electricity supply to the electromagnetic actuator 15 , thereby actuating the electromagnetic actuator 15 . Moreover, the actuator 30 actuates the electromagnetic actuator 15 based on the idling control signal when the control frequency is the set-up frequency F s or less. On the other hand, the actuator 30 actuates the electromagnetic actuator 15 based on the running control signal when the control frequency is higher than the set-up frequency F s .
Subsequently, the generation of a control signal C will be hereinafter described.
(1) Vehicle M Under Idling
Firstly, in the vehicle M under idling, an idling control signal y is produced by synthesizing a fundamental-wave signal component S 1 , a secondary harmonic signal component S 2 and a tertiary harmonic signal component S 3 . Note that the fundamental-wave signal component S 1 is a sine-wave signal of the control frequency, sine-wave signal which is expressed by following equation (2). In the equation, “k”=1, 2 and 3 designate the orders of frequency, “a n and φ n ” designate the amplitude and phase of frequency, “n” designates time, and “offset” designates the offset magnitudes of output computed values, respectively. FIG. 2 illustrates the fundamental-wave signal component S 1 , the secondary harmonic signal component S 2 , and the tertiary harmonic signal component S 3 . FIG. 3 illustrates an output computed value C 1 which is produced by synthesizing the fundamental-wave signal component S 1 , secondary harmonic signal component S 2 and tertiary harmonic signal component S 3 . The idling control signal data storage 24 stores the output computed value C 1 as a data map on frequencies in the vehicle M under idling.
Equation
(
2
)
:
y
(
n
)
=
∑
k
=
1
k
(
a
k
(
n
)
/
2
)
·
sin
(
k
ω
·
Δ
T
·
n
+
ϕ
k
(
n
)
)
+
a
k
(
n
)
/
offset
(2) Vehicle M Under Running
Then, in the vehicle M under running, a running control signal y is an output computed value C 2 , a rectangle-shaped wave. Note that the output computed value C 2 is produced by giving a correction, which is expressed by following equation (4), to a fundamental-wave signal component S 1 . Also note that the fundamental-wave signal component S 1 is a sine-wave signal of the control frequency, sine-wave signal which is expressed by following equation (3) and is free from a secondary harmonic signal component S 2 and a tertiary harmonic signal component S 3 . In the equations, “k”=1, 2 and 3 designate the orders of frequency, “a n and φ n ” designate the amplitude and phase of frequency, “n” designates time, and “offset” designates the offset magnitudes of output computed values, respectively. FIG. 4 illustrates the fundamental-wave signal component S 1 , a sine-wave signal of the control signal. FIG. 5 illustrates the output computed value C 2 which is produced by correcting the base-wave signal component S 1 in accordance with equation (4). The running control signal data storage 26 stores the output computed value C 2 as a data map on frequencies in the vehicle M under running.
Equation ( 3 ) : y ( n ) = ∑ k = 1 k ( a k ( n ) / 2 ) · sin ( k ω · Δ T · n + ϕ k ( n ) ) + a k ( n ) / offset when y (n) ≧0, y (n) =a k(n) ; and when y (n) <0, y (n) =−0.15 Equation (4):
How the vibration controller according to Example No. 1 of the present invention operates will be hereinafter described.
When the vehicle M is under idling, the rotary pulse sensor 12 outputs a rotary pulsating signal S to the controller unit 20 . The signal retriever 21 of the controller unit 20 retrieves the rotary pulsating signal S. Subsequently, the frequency judge 22 judges whether the frequency of the rotary pulsating signal S (or control frequency) is a controlled frequency or not. Then, when the frequency of the rotary pulsating signal S equals the controlled frequency, the set-up frequency judge/switcher 23 judges whether the frequency of the rotary pulsating signal S is a set-up frequency F 2 or less.
Moreover, when the frequency of the rotary pulsating signal S (or control frequency) is the set-up frequency F 2 or less, the idling control signal computer 25 retrieves idling control signal data, which correspond to the amplitude and phase of the rotary pulsating signal S input from the signal retriever 21 , from the idling control signal data storage 24 . In addition, the idling control signal computer 25 generates an idling control signal based on an output computed value C 1 , one of idling control signal data, which is produced by superimposing a fundamental-wave signal component S 1 of the control frequency, a secondary harmonic signal component S 2 and a tertiary harmonic signal component S 3 . Thus, the idling control signal computer 25 outputs the resulting idling control signal to the actuator 30 .
The actuator 30 generates an actuating signal based on the input idling control signal, and turns on the electricity supply for the electromagnetic actuator 15 . When the electromagnetic actuator 15 is actuated, the vibrating forces of the engine mount 15 are applied to the engine 11 . Accordingly, the engine mount 15 inhibits the vibrations of the engine 11 under idling from transmitting.
Note herein that the idling control signal involves the secondary harmonic signal component S 2 and the tertiary harmonic signal component S 3 in addition to the fundamental-wave signal component S 1 , a sine-wave signal of the rotary pulsating signal S (or control frequency). Consequently, not only it is possible to adequately inhibit the engine 11 's vibrations, whose frequency equals the control frequency, from transmitting, but also it is possible to appropriately suppress the generation of noises resulting from the secondary and tertiary harmonic signal components S 2 , S 3 with respect to the control frequency.
On the other hand, when the vehicle M is under high-frequency running, the frequency of a rotary pulsating signal S (or control frequency) is higher than the set-up frequency F s . When the frequency of a rotary pulsating signal S is thus higher than the set-up frequency F s , the running control signal computer 27 retrieves running control signal data, which correspond to the amplitude and phase of the rotary pulsating signal S input from the signal retriever 21 , from the running control signal data storage 26 . Moreover, the running control signal computer 27 computes to generate a running control signal based on an output computed value C 2 . Note that the output computed value C 2 is one of running control signal data, which is produced by correcting a fundamental-wave signal component S, a sing-wave signal of the frequency of the rotary pulsating signals, in accordance with above-described equation (3). Thus, the running control signal computer 27 outputs the resultant running control signal to the actuator 30 .
The actuator 30 generates an actuating signal based on the input running control signal, and turns on the electricity supply for the electromagnetic actuator 15 . When the electromagnetic actuator 15 is actuated, the vibrating forces of the engine mount 15 are applied to the engine 11 . Accordingly, the engine mount 15 inhibits the vibrations of the engine 11 under running from transmitting.
In this way, the running control signal results from the output computed value C 2 , a rectangle-shaped wave signal which is converted from the sine-wave signal of the frequency of the rotary pulsating signal S (or control signal). Accordingly, when actuating the electromagnetic actuator 15 exhibiting slow response, the rectangle-shaped wave signal can compensate the retarded response of the electromagnetic actuator 15 . Consequently, the engine mount 15 can produce vibrating forces sufficiently.
As described above, the vibration controller according to Example No. 1 of the present invention actuates the electromagnetic actuator 15 with the idling control signal and the running control signal, which are distinctive to each other for controlling low-frequency vibrations of the vehicle M under idling and high-frequency vibrations of the vehicle M under running, individually. Therefore, the vibration controller can suppress the generation of noises resulting from the secondary harmonic signal component S 2 and tertiary harmonic signal component S 3 in the vehicle M under idling. At the same time, the vibration controller can securely produce sufficient vibrating forces in the vehicle M under running even when the vibration controller uses the less expensive electromagnetic actuator 15 with slow response. As a result, the vibration controller can inhibit the vibrations of the engine 11 from transmitting over a wide range of the vehicle M's driving conditions entirely, even using the less expensive electromagnetic actuator 15 , while suppressing the generation of noises.
EXAMPLE NO. 2
A vibration controller according to Example No. 2 of the present invention, a modified version of Example No. 1, will be hereinafter described.
In the vibration controller according to Example No. 2 of the present invention, an idling control signal y for inhibiting the low-frequency vibrations of the engine 11 under idling from transmitting comprises a fundamental-wave signal component, a secondary harmonic signal component S 2 , and a tertiary harmonic signal component S 3 which are superimposed one after another. Specifically, as illustrated in FIG. 6 , the fundamental-wave signal component is a rectangle-shaped wave signal P 1 which is expressed by following equation (5). The secondary harmonic signal component S 2 and tertiary harmonic signal component S 3 are sine-wave signals similarly to those of Example No. 1. Note that the notations in equation (5) are identical with those in above-described equations (2) through (4). FIG. 6 illustrates the rectangle-shaped wave signal component P 1 as the fundamental-wave signal component, and the sine-wave signals as the secondary harmonic signal component S 2 and tertiary harmonic signal component S 3 . FIG. 7 illustrates an output computed value C 3 which are produced by synthesizing the rectangle-shaped wave signal component P 1 , secondary harmonic signal component S 2 and tertiary harmonic signal component S 3 . Note that the upper value of the absolute output computed value C 3 is set at 1. The idling control signal data storage 24 stores the output computed value C 3 as a data map on frequencies in the vehicle M under idling.
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The vibration controller according to Example No. 2 of the present invention uses the idling control signal y, which involves the secondary harmonic signal component S 2 and tertiary harmonic signal component S 3 in addition to the rectangle-shaped wave signal component P 1 , the fundamental-wave signal component of the control frequency. When the fundamental-wave signal component of the control signal thus comprises a rectangle-shaped wave signal, it is possible to enhance the vibrating forces of the engine mount 14 because the rectangle-shaped wave signal compensates for the insufficient response of the slow-response electromagnetic 15 as well. Therefore, it is possible to adequately inhibit the engine 11 's vibrations, whose frequencies equal the control frequency, from transmitting. Moreover, it is possible to appropriately suppress the generation of noises resulting from the secondary harmonic signal component S 2 and tertiary harmonic signal component S 3 with respect to the control frequency.
In the vibration controllers according to Example Nos. 1 and 2 of the present invention, the data storages 24 , 26 store the control signal data which are found in advance for the idling control signal and running control signal; and the computers 25 , 27 select one of the control signal data from the data storages 24 , 26 to generate the idling control signal and running control signal. However, not limited to this, it is possible as well to generate the idling control signal and running control signal by adaptive control methods, for example. In addition, Example Nos. 1 and 2 described above are a few examples of the present invention. Therefore, it is possible to carry out the present invention with various changes and modifications as far as they do not deviate from the gist of the present invention.
INDUSTRIAL APPLICABILITY
In accordance with a method for actuating active vibration insulators according to the present invention, electromagnetic actuators are actuated with an idling control signal and a running control signal, which are distinctive to each other for controlling low-frequency vibrations of vehicles under idling and high-frequency vibrations of vehicles under running, individually. Therefore, the present method can suppress the generation of noises resulting from secondary harmonic signal components and tertiary harmonic signal components with respect to control frequencies in vehicles under idling. Moreover, when the present method employs a rectangle-shaped wave signal, which is produced by converting a sine-wave signal of control frequencies into a rectangle-shaped wave, as the running control signal for inhibiting high-frequency vibrations of running vehicles from transmitting, it is possible even for less expensive electromagnetic actuators with slow response to securely produce sufficient vibrating forces. Thus, the present method can inhibit vibrations of engines from transmitting over a wide range of vehicles' driving conditions entirely, even using less expensive electromagnetic actuators, while suppressing the generation of noises. Hence, the present method is useful industrially.
Having now fully described the present invention, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the present invention as set forth herein including the appended claims. | A method for actuating active vibration insulators includes the steps of generating an idling control signal in an idling range of a vehicle, generating a running control signal in a running range of the vehicle, and actuating an electromagnetic actuator of an active vibration insulator based on the idling control signal or the running control signal, thereby inhibiting vibrations of a vehicle engine from transmitting by the electromagnetic actuator. The idling control signal is produced by adding a higher order harmonic signal component with respect to a control frequency, based on a cyclic pulsating signal emitted from the vehicle engine, to a fundamental-wave signal component of the control frequency. The running control signal is composed of the fundamental-wave signal component of the control signal. The method can inhibit noises from generating by actuating simple electromagnetic actuators, and can damp vibrations of vehicle engines simply and less expensively. | 5 |
CROSS REFERENCES TO RELATED PATENT APPLICATIONS
This is a continuation-in-part utility patent application based upon the invention disclosed in U.S. patent application Ser. No. 09/677,705 to the same inventor, filed Sep. 30, 2000, and has been allowed to issue as U.S. Pat. No. 6,709,339, which is a continuation-in-part utility patent application based upon the invention disclosed in U.S. patent application Ser. No. 09/375,894 to the same inventor, filed Aug. 17, 1999, now abandoned, and benefit of the previous co-pending patent applications is requested herein.
BACKGROUND
1. Field of Invention
This invention relates to devices for creating infinity mirror display effects, specifically to an openable infinity mirror display case or apparatus, and a method for its manufacture, which has a base member that remains stationary during use, an easily removable cover that is placed during use in a closed position against the base member to define an interior space, an illumination means communicating with the interior space, and at least one display object placed between the cover and the base member with the illumination means lighting it, where the cover or base member together comprising two or more at least partially mirrored surfaces, or otherwise partially reflective surfaces, in opposed positions whereby when the cover is placed into its closed position and an observer viewing display objects in the interior space through at least one of the partially mirrored or partially reflecting surfaces will see at least one row of alternating front and rear reflected images of each display object used extending rearwardly from it. When three or more partially reflecting surfaces are used at right angles to one another, with a fully reflective surface connected parallel to and behind the center one of the partially reflective surfaces, and an observer looks only through the center surface, multiple rows of reflected images that contain alternating front and rear images of the display object also appear parallel to and on both sides of the row of reflected images extending directly behind the display object. In the alternative, when an observer looks at the display object or objects within the interior space from the substantially perpendicular connection between the center partially reflective surface and the one to its left, the observer will view multiple parallel rows of reflected images (alternatively front and rear reflected images) extending rearwardly from the display object and laterally to the right. In contrast, when an observer looks at the display object or objects within the interior space from the substantially perpendicular connection between the center partially reflective surface and the one to its right, the observer will view multiple parallel rows of reflected images (alternatively front and rear reflected images) extending rearwardly from the display object and laterally to the left. The intensity of display object illumination and the amount of light transmission possible through the partially reflective viewing surfaces determines the number of reflected images an observer will see, and the capability for the present invention infinity display apparatus cover to be moved away from its closed position sufficiently for new display objects to be readily placed within the interior spaced defined by the cover and base member allows the infinity mirror display effect to be continually updated and renewed to maintain viewer interest. Optionally, a variety of support surfaces and support devices may be employed within the housing for securely positioning a selection of display objects in different locations within the housing so that the display objects can be used without modification or alteration. Also, different types of illuminations sources, including multiple light sources, are contemplated for use in illuminating the display objects. Prompt display object exchange is important for private and commercial applications, such as but not limited to creating an infinity mirror display effect for a hobbyist having a grouping of collectible objects small enough to be placed within the interior space, such as die-cast metal cars, so that when the hobbyist makes additions to his or her collection, the new acquisitions can easily and readily be displayed; for point-of-sale displays in commerce that direct customers' attention to newly received merchandise; for commercial use by establishments such as restaurants, bars, night clubs, hotels, and antique shops where varying numbers of objects can be featured on a rotating basis for general public viewing, to create an interesting and exciting work environment for attracting and maintaining good employees, to create public interest in a particular topic, to create an interest in the establishment for attracting new and repeat customers, to provide a basis for conversation among existing customers, and to maintain consumer and public interest in the establishment; for dust-free enhanced display of trophies and awards by individuals and organizations so that new acquisitions can be easily placed along side of those earlier received; for enhanced display of autographed items such as baseballs or baseball cards with the possibility of quick-exchange of one item for another whenever the owner desires; for the opportunity for enhanced display of any currently favored personal treasures or art objects with the opportunity at any time for the owner to easily and rapidly exchange one or more of them for a newly favored treasure or art object to create an ever changing variety of infinity mirror display effects for observer enjoyment; and for addition as an incorporated part of larger devices, to enhance their marketability, eye appeal, and usage by the public, such as use with juke boxes and the like, as well as skill/gaming devices including those that allow a player to pay a fee and them employ a crane to select one object among a grouping or various sized objects, some more valuable than others, with the present invention providing the receptacle into which the successfully selected object is displayed prior to being released to the player, wherein the present invention would add to the visual entertainment of the player and perhaps assist in enticing him or her to play again.
2. Description of Related Art
The infinity mirror effect is a principle disclosed in U.S. Pat. No. 4,761,004 to Hargabus (1988) and various other patents. Through the use of a mirror or other partially reflective surface positioned between a viewer and a totally reflective surface, and when the two reflective surfaces are oriented approximately parallel to one another, illuminated objects placed between the two reflective surfaces and viewed from any direction other than a straight-forward position will be observed to have multiple, spaced-apart reflections extending rearwardly therefrom. Differing effects can be created by placing one of the reflecting surfaces at an oblique angle relative to the other, and by adding more partially reflective surfaces. The infinity mirror display effect will be composed of multiple, alternating front and back, spaced-apart reflections extending rearwardly from each display object used with a grouping of reflective surfaces able to create the effect, with each newly repeated image being slightly smaller and diminished in brightness when compared to the next adjacent image. One disadvantage of prior art infinity display devices is that once a three-dimensional display object is placed in its operative position relative to the mirrors, it is not easily exchanged for another. This limits the use of prior art devices for display of collectibles and other favored objects for which new acquisitions are periodically being made. Also limited is the ease in which new visual effects can be created by the exchange of a previous collection of objects for one or more new objects. The present invention provides several alternative embodiments for creating an infinity mirror display apparatus that can be effectively used for the display of multiple three-dimensional objects, and then permit the nearly instantaneous exchange or addition of displayed objects, even those requiring a suspended means of support for best viewing. No device is known that has all of the advantages of the present invention.
BRIEF SUMMARY OF THE INVENTION—OBJECTS AND ADVANTAGES
The primary object of this invention is to provide an infinity mirror display apparatus configured for displaying multiple spaced-apart reflections extending rearwardly and perhaps also laterally from one or more illuminated display objects positioned in the interior space defined between a stationary base member and a removable cover, and which is adapted to permit nearly instantaneous access to the interior space so that three-dimensional display objects can be quickly and easily added and removed therefrom. It is also an object of this invention to provide an infinity mirror display apparatus that can remain in its mounted position during display object exchange or addition. A further object of this invention is to provide an infinity mirror display apparatus that includes multi-sided covers. It is also an object of this invention to provide an infinity mirror display apparatus in which the display objects can be freely exchanged and do not require any permanent modification or alteration for secure positioning within the housing. A further object of this invention is to provide an infinity mirror display apparatus that permits rapid and easy access to its interior space for nearly instantaneous removal or addition of display objects without disturbing other objects already positioned for display within the housing. It is also an object of this invention to provide an infinity mirror display apparatus having light sources that can be positioned anywhere that communicates with the interior space of the housing, including above or below a display object support, as well as in any direction or orientation relative to display objects that are suspended within the interior space, in direct contact with the bottom interior surface of the stationary base member, or positioned upon a display support.
As described herein, properly manufactured and used, the present invention infinity mirror display apparatus would enable those having a selection of objects for infinity effect display to be able to display one or more of them at a time, or in succession, in a variety of different combinations within the closed interior spaced of a housing defined by a stationary base member and a complementary cover in its closed position against the base member. Its easily-opened hinged, sliding, or detachable cover would comprise at least one partially reflective mirrored surface, or other partially reflective surface, through which a viewer would observe illuminated display objects and the multiple reflections produced rearwardly, and perhaps also laterally, therefrom that create the infinity mirror display effect. A second mirrored or other reflective surface that is either a partially or totally reflective surface, is positioned within or adjacent to the interior space behind the object or objects intended for display, remote from the viewer. As soon as the display objects become illuminated by a light source communicating with the interior space, the infinity mirror display effect is created. When the openable cover comprises the partially reflective surface used by an observer to view the infinity display effect, the cover must be closed to see the multiple images. However, when the openable cover is positioned above the partially reflective surface used by an observer to view the infinity display effect, multiple images can be seen even while the cover is open and display objects are being exchanged. Placement of the removable cover into its fully opened position, or one of a plurality of partially opened positions sufficient to allow passage of the largest display object targeted for exchange, permits rapid and easy access to the interior space of the housing for nearly instantaneous removal and/or addition of selected display objects, or prompt optional replacement of all display objects within the housing. Rapid opening of the cover can be accomplished through use of one or more hinges on any perimeter edge of the stationary base member, a perimeter groove in the stationary base member that allows the associated cover to slide within the groove between opened and closed positions, or by easily lifting the cover vertically away from its associated stationary base member. Since the cover is easily removed and placed into its fully opened position, or one of a plurality of partially opened positions that allow passage of the largest display object targeted for exchange, display objects can be quickly added or removed from the interior space of the housing without having to dismantle the stationary base member or cover, disturb the stationary base member from its mounted position, and without disturbing other objects already positioned for display within the interior space of the housing. Since the housing would not need to be rotated or positioned on its side for access to its interior space, display objects do not require any permanent modification or alteration for secure positioning within the housing and can be freely and instantaneously lifted from a display position for exchange. Also, since the housing would not need to be rotated or positioned on its side for access to its interior space, other objects already positioned for display within the housing are not disturbed when selected display objects are removed and/or when new display objects are added to a collection of objects already on display within the housing. Further, the display objects can be mounted in a variety of positions within the infinity mirror display apparatus housing, such as through use of suction cups or a bonded connection to one or more of the partially reflective surfaces in the cover employed by an observer to view the infinity display effect, one or more transparent or translucent movable support members placed directly upon the bottom interior surface of the housing, flexible filamentous materials suspended from anchoring devices such as hooks or rings supported by the top interior surface of the stationary base member or a multiple-sided cover, and elevated support members detachably and adjustably connected to peg holes formed in or attached to the vertically extending walls of a stationary base member or a multiple-sided cover. As a result, the light sources used to illuminate the diversely positioned display objects can also be positioned within any part of the housing and in any direction or orientation relative to the display objects, often providing illumination from below. Also, the size, number, and orientation of the reflective surfaces relative to one another can be varied, and although a more uniform infinity display effect is created when there is a close positioning of display object and reflective or partially reflective surface, interesting infinity display effects can also be created when more than two partially reflective surfaces are used and when reflective surfaces are positioned at oblique angles relative to one another. Therefore the configuration and dimensions of the stationary base member and cover are not limited as long as together they provide a means of enclosed support for all of the reflective surfaces selected for use, as well as an enclosed interior space of sufficient dimension for housing the maximum number of objects intended for simultaneous display and the amount of illumination needed to create a pleasing infinity display effect therewith. As a result, it is contemplated that the size of a housing used in the present invention would depend upon several factors such as but not limited to the cost of the materials used for its construction, the size and decor of the room where it would be used, and whether it would be wall-mounted or table-mounted. Further, when restricted access to one or more display objects within the interior space is desired, such as in a commercial application where the display items are highly desired or valuable, it is contemplated for the present invention to comprise a locking device that would prevent unauthorized separation of the cover from the stationary base member.
The description herein provides the preferred embodiments of the present invention but should not be construed as limiting the scope of the infinity mirror display apparatus. For example, variations in the length, width, and thickness dimensions of the stationary base member and its complementary cover; the size of the interior space defined by the stationary base member and its complementary cover; the total surface area of each of the reflective or partially reflective surfaces used to create the infinity display effect relative to the others; the type of locking means optionally used between the cover and the stationary base member to prevent unauthorized access to the interior space; and the means used to securely position display objects within the interior space of the housing other than those shown and described herein may be incorporated into the present invention. Thus the scope of the present invention should be determined by the appended claims and their legal equivalents, rather than the examples given.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a front perspective view of a first preferred embodiment of the present invention having a rectangular housing with a box-like stationary base member and a totally reflective surface attached to its rear inside surface, a substantially planar cover hinged to one side of the stationary base member and comprising a partially reflective surface supported by a frame, closure means between the stationary base member and the cover, multiple lights vertically extending in opposed lateral positions within the interior space adjacent to the totally reflective surface, and one display object positioned within the interior space and being supported directly by the housing.
FIG. 2 is a front perspective view of a second preferred embodiment of the present invention having a rectangular housing with a box-like stationary base member and a totally reflective surface attached to its rear inside surface, a substantially planar cover hinged to one side of the stationary base member and comprising a partially reflective surface supported by a frame, magnetic closure means positioned between the stationary base member and the cover, a rectangular display support having a transparent or translucent upper surface and being positioned within the bottom part of the stationary base member, a light source positioned below the display support, and one display object placed directly on the upper surface of the display support.
FIG. 3 is a front view of the first preferred embodiment of the present invention having its cover in a fully closed position, a locking closure means for the cover, a display object positioned upon a movable support member within the interior space defined by the box-like stationary base member and the cover, and multiple reflective images creating an infinity mirror effect extending rearwardly from the display object, the movable support member, and the multiple lights positioned laterally against the totally reflective surface that is attached to the rear inside surface of the stationary base member.
FIG. 4 is a front perspective view of a third preferred embodiment having a rectangular housing with a box-like stationary base member and a mirror attached to its rear inside surface, a substantially planar cover vertically slidable within grooves formed laterally in the stationary base member near to its front perimeter, the cover comprising a frameless partially reflective surface, and multiple lights positioned within the interior space defined by the stationary base member and the cover, and placed laterally against the totally reflective surface that is attached to the rear inside surface of the stationary base member.
FIG. 5 is a front perspective view of a fourth preferred embodiment of the present invention having a rectangular housing with a box-like stationary base member and a mirror attached to its rear inside surface, a substantially planar cover hinged to one side of the stationary base member and comprising a frameless partially reflective surface, magnetic closure means positioned between the stationary base member and the cover, multiple lights positioned within the interior space defined by the stationary base member and the cover, and placed laterally against the totally reflective surface that is attached to the rear inside surface of the stationary base member, a hooked display object support device and cord adapted for suspending a display object within the interior space, and one suspended display object connected to the hooked display support device.
FIG. 6 is a front view of a fifth preferred embodiment of the present invention having a rectangular housing with a hinged front cover made from a partially reflective surface supported by a frame, the cover being in its fully closed position, a rearwardly positioned reflective surface, and three display objects positioned between the cover and the rearwardly positioned reflective surface, one of the display objects positioned upon a movable support member placed on the bottom interior surface of the housing, with two additional display objects each being positioned upon a movable support member, with one of the movable support members being attached to the partially reflective surface by suction cup means and the other movable support members being bonded to the partially reflective surface.
FIG. 7 is a left side view of a sixth preferred embodiment of the present invention having a housing with a box-like stationary base member and a reflective surface attached to its rear inside surface with its reflective side against the rear inside surface of the stationary base member, a substantially planar cover closed against the stationary base member and comprising a partially reflective surface supported by a frame, a display support having a transparent or translucent upper surface positioned in the bottom part of the stationary base member, a light source positioned under the display support, a display object positioned on top of a movable support member placed centrally upon the display support, and a vertically extending mounting strip on the wall of the housing behind the display object with holes therein for adjustable positioning of elevated support members having complementary protrusions for the optional elevated display of additional objects between the stationary base member and its cover.
FIG. 8 is a front view of a seventh preferred embodiment of the present invention having a housing with a box-like stationary base member and a reflective surface attached to its rear inside surface, a substantially planar cover hinged to one side of the stationary base member and comprising a frameless partially reflective surface supported by a frame, two-part closure means for securely positioning the cover against the stationary base member when the cover is in its fully closed position, multiple lights positioned within the interior space defined by the stationary base member and the cover, three display objects positioned between the cover and the rearwardly positioned reflective surface, two opposed sets of vertically extending peg holes formed in the sides of the stationary base member with each set being on a different side of the display objects and adapted for adjustable positioning of elevated support members at different heights within the interior space, with one of the display objects being positioned upon a movable support member placed on the bottom interior surface of the housing, and a second display object being positioned upon an elevated support members attached to two peg holes on one side of the stationary base member, and a third display object positioned upon an elevated support member having protrusions and ready for connection to peg holes on the opposed side of the stationary base member.
FIG. 9 is a front perspective view of an eighth preferred embodiment of the present invention having a hexagonal housing with a substantially planar platform-like stationary base member and display support with a transparent or translucent top surface positioned above the stationary base member, a display object being supported by a movable support member centrally atop the display support, multiple lights positioned under the perimeter of the display support, and a box-like cover that can be vertically lifted from the stationary base member to give access to the interior space defined by the stationary base member and the cover, the cover being poised over the stationary base member in an open position allowing display object exchange, the cover comprising adjoining frameless partially reflective surfaces.
FIG. 10 is a front perspective view of a ninth preferred embodiment of the present invention having a rectangular housing with a substantially planar platform-like stationary base member and a light source attached through the upper surface of the stationary base member, a display support having a transparent or translucent top surface poised above the stationary base member, a display object being supported by a movable support member centrally atop the transparent or translucent top surface of the display support, and a box-like cover that is vertically lifted from the stationary base member to give access to the interior space defined by the stationary base member and the cover, the cover being poised over the stationary base member in an open position allowing display object exchange, the cover comprising adjoining partially reflective surfaces each supported by a frame.
FIG. 11 is a front view of a tenth preferred embodiment of the present invention having a rectangular housing, a light source attached through the upper surface of the stationary base member, and a hinged cover that lifts vertically upward from the stationary base member to give access to the interior space defined by the stationary base member and the cover, with an upwardly directed arrow showing that the cover is vertically openable from the closed position shown.
FIG. 12 is a perspective view of an eleventh preferred embodiment of the present invention having a rectangular housing and a multi-sided cover that separates from the stationary base member to give temporary access to the interior space defined by the stationary base member and the cover between infinity display uses.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1–8 show several box-like embodiments each with an openable front cover 6 containing one partially reflective surface or other reflective surface 8 . Together FIGS. 1–8 show a variety of display objects 24 , illumination means 18 and 32 , and display object supports 34 , 40 , 84 , 54 , and 52 used with the box-like embodiments, and which could also be adapted for the other embodiments in FIGS. 9–12 . In contrast, FIGS. 9–10 show two preferred embodiments that have a cover 76 with multiple reflective surfaces 8 that is vertically raised and lowered from its stationary base member 4 for the exchange of display objects 24 . FIG. 11 shows a box-like embodiment with an openable front cover 6 containing more than one partially reflective surface or other reflective surface 8 , and FIG. 12 shows a box-like embodiment with a cover 6 that is vertically raised and lowered from its stationary base member 4 for the exchange of display objects 24 .
FIG. 1 shows a first preferred embodiment 2 of the present invention having a rectangular housing with a box-like stationary member 4 having five enclosed sides, an open sixth side, and a totally reflective surface 10 attached to its rear inside surface. Although not limited thereto, first preferred embodiment 2 would preferably be wall-mounted, with totally reflective surface 10 generally being in a position remote from an observer (not shown). Since it is contemplated for any commonly used type of wall mounting bracket or means to be attached to or used within the back surface of stationary base member 4 for securing it against a wall surface, and further since the number of mounting brackets or other type of mounting means used is also not critical, illustrations of the mounting hardware alternatives possible for wall attachment of first preferred embodiment 2 have not been provided. FIG. 1 also shows first preferred embodiment 2 having a substantially planar cover 6 attached to one side of stationary base member 4 with an elongated hinge 12 . Although FIG. 1 shows one elongated hinge 12 , the use of a single elongated hinge 123 is not critical and it is also considered to be within the scope of the present invention for first preferred embodiment 2 to have other types and sizes of connecting devices between cover 6 and stationary base member 4 , including releasable fasteners such as magnetic fasteners 30 a and 30 b shown in FIG. 2 , locking fasteners such as keyed fastener 44 shown in FIG. 3 , supportive grooves, such as groove 48 shown in FIG. 4 , and other similar devices that securely hold cover 6 against stationary base member 4 while at the same time are easily manipulated by a user for prompt separation of cover 6 from stationary base member 4 . Also, the side of stationary base member 4 to which hinge 12 is attached is not critical, and as an alternative to the left perimeter edge of stationary base member 4 shown in FIG. 4 , hinge 12 could also be attached to the right perimeter of stationary base member 4 , its top perimeter edge wherein the bottom edge of stationary base member 4 would open in a forward and upwardly direction, or the bottom perimeter edge of stationary base member 4 wherein the top edge of cover 6 would open in a forward and downwardly direction. Since the infinity display effect requires a minimum of two mirrored surfaces, with at least one being partially reflective, FIG. 1 shows cover 6 comprising a partially reflective surface 8 centrally supported within a frame to complement the totally reflective surface 10 attached to the back interior surface of stationary base member 4 for infinity display effect purposes. Cover 6 would not need to be totally closed against stationary base member 4 for viewing an infinity display effect through partially reflective surface 6 , however, the number of repeated images in the infinity display effect decreases as hinged cover 6 is rotated away from totally reflective surface 10 . Although not shown in FIG. 1 , but visible in FIG. 7 and identified by the number 86 , it is contemplated and preferred for partially reflective surface 8 to be held securely within the frame of cover 6 by a minimum of four angular S-shaped mounting brackets 86 , each in contact with partially reflective surface 8 and the frame of cover 6 near to their respective corners. However, although it is contemplated for angular S-shaped mounting brackets 86 to be used in first preferred embodiment 2 , the use of angular S-shaped mounting brackets 86 is not critical, and it is considered within the scope of the present invention for other types and configurations of commonly used mirror-to-frame mounting brackets to be employed. When there is no illumination between partially reflective surface 8 and totally reflective surface 10 , partially reflective surface 8 would reflect the image of an observer viewing it. However, when illumination does exist behind partially reflective surface 8 , an observer would be able to see through partially reflective surface 8 and view illuminated objects positioned behind it, such as display object 24 in FIG. 1 , which is shaped as a trophy and shown positioned directly on the bottom inside surface 16 of stationary base member 4 . Since cover 6 is easily opened without disturbing stationary base member 4 , display objects 24 would no need to be permanently secured or anchored within stationary base member 4 , during their use in providing an infinity display effect. In the first preferred embodiment shown in FIG. 1 , the left and right sides of stationary base member are unmarked as being opaque, with the sole partially reflective surface 8 used being a part of cover 6 . However, variations of the first embodiment also considered within the scope of the present invention could include either the left or right side of stationary base member 4 , or both, containing partially reflective surfaces 8 , cover 6 containing more than one partially reflective surface 8 , the top surface of stationary base member 4 containing a partially reflective surface 8 , and even the back surface of stationary base member 4 containing a partially reflective surface 8 in place of totally reflective surface 10 , particularly when a bottom positioned source of light is used, such as light source 32 shown in FIG. 2 , instead of the elevated strand of multiple miniature lights 18 used in the first preferred embodiment 2 .
FIG. 1 also shows a two-part fastener consisting of first fastener 14 a and second fastener 14 b being use to achieve secure closure of cover 6 against stationary base member 4 when cover 6 is in its fully closed position. The type of fastening means used for first fastener 14 a and second fastener 14 b is not critical and any type or number of secure but easily opened closure means, such as a snap-fit type of closure, as well as locking closure means between the stationary base member 4 and cover 6 , such a keyed fastener 44 in FIG. 3 , are considered to be within the scope of the present invention as long as all are easily manipulated for prompt access to the interior space defined between stationary base member 4 and cover 6 . A handle could optionally be positioned on the reverse side of cover 6 not visible in FIG. 1 , anywhere along the distal edge of the frame of cover 6 in a position remote from hinge 12 . However, generally a handle is not preferred and instead cover 6 can be made to slightly overlap the perimeter of stationary base member 4 , at least one the perimeter edge of the frame of cover 6 that is remote from hinge 12 , so as to provide an easily gripped hand-hold for manipulating cover 6 between it fully closed position and its fully opened position. FIG. 1 also shows a strand of multiple miniature lights 18 extending vertically along the left side of display object 24 in a position adjacent to the perimeter edge of totally reflective surface 10 . Since no infinity mirror effect would be possible with cover in its fully opened position, only a single reflected image 20 of miniature lights 18 and display object 24 are shown behind them. Since it is preferred that miniature lights 18 would extend across the top perimeter edge of totally reflective surface 10 , as well as along both vertically extending side perimeter edges, a reflected image 20 of miniature lights 18 is also shown to the right of display object 24 , the miniature lights 18 on the right side of display object 24 remaining hidden from view behind stationary base member 4 . Although not shown in FIG. 1 and not necessarily needed if a display support 34 is used beneath display object 25 , similar to that shown in FIG. 2 , since a display support 34 would preferably have small openings therethrough laterally on its back edge for securing the ends of miniature lights 18 , in the first preferred embodiment 2 miniature lights 18 could be supported by several small transparent, translucent, or opaque U-shaped brackets 82 , as shown in FIG. 5 . Secure attachment of U-shaped brackets 82 to totally reflective surface 10 could be achieved by adhesive or bonding agent means (not shown). FIG. 1 also shows the electrical cord 22 needed for connecting miniature lights 18 to a source of electrical power (not shown) and an on-off switch 26 for use in activating miniature lights 18 for illumination of display object 24 and the instantaneous creation of an infinity mirror display effect when cover 6 is fully closed, or nearly closed, against stationary base member 4 and display object 24 is viewed through partially reflective surface 8 . Although it is preferred for electrical cord 22 to extend through a small opening in the back surface of stationary base member 4 near to its bottom surface, and for on-off switch 26 to be conveniently positioned close to stationary base member 4 for easy access thereto, such connections are not critical. Further, although on-off switch 26 is show to have a rotating dick type of switch activation means for aesthetic purposes, it is considered to be within the scope of the present invention, although not shown, for on-off switch 26 to also have a toggle, depressible button, rotatable knob, or other type of electrical activation means.
The materials used for cover 6 and stationary base member 4 in first preferred embodiment 2 can vary, and although not limited thereto it is contemplated for the frame portion of cover 6 and stationary base member 2 to be made from rigid materials capable of respectively supporting totally reflective surface 10 and partially reflective surface 8 , such as but not limited to wood, metal, plastic materials, ceramic materials, and the like. Although not show, the interior surfaces of stationary base member 4 , other than the back interior surface to which totally reflective surface 10 is attached, can be lined with a fabric, such as felt, and/or other aesthetically pleasing materials. However, if such lining were used, although not limited thereto, they would generally consist of non-shiny fabrics in a variety of dark or subdued colors, unless needed for a particular use to enhance an infinity effect display effect. Also, although it is contemplated in first preferred embodiment 2 for totally reflective surface 10 and partially reflective surface 8 to be made from glass and for totally reflective surface 10 to be a conventional silvered mirror, it is considered to be within the scope of the present invention for totally reflective surface 10 and partially reflective surface 8 to comprise other reflective materials. Also in the first preferred embodiment 2 shown in FIG. 1 , although totally reflective surface 10 and partially reflective surface 8 are shown to be substantially parallel to one another, positioning at oblique angles relative to one another can provide pleasing visual effects and therefore respective oblique positioning of totally reflective surface 10 and partially reflective surface 8 to the other is also considered to be within the scope of the present invention.
Although not limited thereto and provided herein only as an example, the dimensions of first preferred embodiment 2 for creating a pleasing infinity display effect with a display object having a height dimension of approximately four inches and a diameter dimension of approximately two-and-one-half inches, could include box-like stationary base member 4 having a width dimension of approximately ten inches, a height dimension of approximately twelve inches, and a depth dimension of approximately four inches. Corresponding dimensions for cover 6 , which would provide a small amount of stationary base member overlap to create a hand-hold for easily opening cover 6 without the need for a handle, would include a width dimension of approximately ten-and-one-half inches, a height dimension of approximately twelve-and-one-half inches, and a depth dimension of approximately one-half of an inch. Cover 6 would have a centrally positioned opening with width and height dimensions respectively of approximately seven and nine inches, through which partially reflective surface 8 is used to view display objects 24 positioned within the interior space defined by cover 6 and stationary base member 4 . To center the slightly larger cover 6 against stationary base member 4 , hinge 12 would be attached between the rear surface of cover 6 and stationary base member 4 , as is more clearly illustrated in FIG. 2 , with hinge 12 generally hidden from an observer by the perimeter edge of cover 6 . As an alternative to one elongated hinge 12 having a length dimension of approximately eleven inches, the first preferred embodiment could also comprise two smaller hinges 12 each having a length dimension of approximately one-and-one-half inches and a spaced-apart distance therebetween of approximately five inches. Also in the first preferred embodiment 2 , partially reflective surface 8 would have width, length, and thickness dimensions respectively of approximately eight-and-one-half inches, ten-and-one-half inches, and one-fourth of an inch. Similarly, totally reflective surface 10 would also have width, length, and thickness dimensions respectively of approximately eight-and-one-half inches, ten-and-one-half inches, and one-fourth of an inch. If a supporting surface other than the bottom inside surface 16 of stationary base member 4 were used for display object 24 , such as the display support 34 shown in FIG. 2 , it would have approximate length, height, and depth dimensions respectively of approximately nine inches, one-and-one-half inches, and two-and-one-half inches. When a strand of miniature lights 18 are used against the top and side perimeter edges of totally reflective surface 10 for illumination of display objects 24 placed between totally reflective surface 10 and partially reflective surface 8 , it is preferred for miniature lights 18 to have a maximum diameter dimension of approximately one-half inch. Also, when display support 34 is used with miniature lights 18 , although not shown, it is contemplated that a small opening would be placed laterally through each back edge of display support 34 for the insertion therethrough of a different one of the opposing ends of miniature lights 18 to help secure miniature lights 18 in their usable position. In the first preferred embodiment 2 electrical cord 22 would be approximately four feet in length, with on-off switch 26 being connected to electrical cord 22 within a conveniently accessible distance of approximately eight inches from stationary base member 4 . On-off switch 26 would preferably have a maximum length dimension of approximately one-and-one-half inches, and maximum width and depth dimensions of approximately one-half of an inch. On-off switch 26 would also preferably have one rotating disk for use in activating miniature lights 18 , although other activation means such as a depressible button, rotatable know, or toggle switch (not shown) could also be used. When the above dimensions are used in first preferred embodiment 2 , and an observer's line of sight is approximately directed to the top of display object 24 , the infinity mirror display effect created rearwardly from display object 24 will extend nearly to the top perimeter edge of totally reflective surface 10 .
FIG. 2 shows a second preferred embodiment 28 of the present invention having a rectangular housing with a box-like stationary base member 4 and a totally reflective surface 10 attached to its rear inside surface, a substantially planar cover 6 connected with hinges 36 to one side of stationary base member 4 and comprising a partially reflective surface 8 supported by a frame, magnetic closure means 30 A and 30 B positioned between stationary base member 4 and cover 6 , a rectangular display support 34 having a transparent or translucent upper surface 38 and being positioned within the bottom part of stationary base member 4 , a light source 32 positioned below display support 32 , and one display object 24 placed directly on the upper surface 38 of display support 34 . Although multiple reflections 20 of display object 24 would only be observed with cover 6 in its closed position, reflections are shown in FIG. 2 for illustrative purposes only. In addition, FIG. 2 shows an electric cord 22 with and on-off switch 26 connected through stationary base member 4 for activation of light source 32 . In contrast, FIG. 3 shows first preferred embodiment 2 of the present invention having its cover 6 comprising a partially reflective surface 8 in a fully closed position against stationary base member 4 , a locking closure means 44 for cover 6 , a display object 24 positioned upon a movable support member 40 within the interior space defined by box-like stationary base member 4 and cover 6 , multiple lights 18 , an electric cord 22 with and on-off switch 26 connected through stationary base member 4 for activation of multiple lights 18 , and multiple reflective images 42 creating an infinity mirror display effect extending rearwardly from display object 24 , movable support member 40 , and the multiple lights 18 positioned laterally against the totally reflective surface 10 that is attached to the rear inside surface of stationary base member 4 .
FIG. 4 shows a third preferred embodiment 46 having a rectangular housing with a box-like stationary base member 4 and a fully reflective rear inside surface 10 , a substantially planar cover comprising a frameless partially reflective surface 8 that is vertically slidable within grooves 48 formed laterally in stationary base member 4 near to its front perimeter, and multiple lights 18 positioned within the interior space defined by stationary base member 4 and the partially reflective surface 8 comprising a cover, with lights 18 placed laterally against the totally reflective surface 10 that is comprises the rear inside surface of stationary base member 4 . FIG. 5 also reveals a fourth preferred embodiment 50 of the present invention having a rectangular housing with a box-like stationary base member 4 and a fully reflective rear inside surface 10 , a substantially planar cover 6 hinged to one side of the stationary base member and comprising a frameless partially reflective surface 8 , magnetic closure means 30 A and 30 B positioned between the stationary base member 4 and the cover 6 , multiple lights 18 positioned within the interior space defined by stationary base member 4 and cover 6 and placed laterally against the totally reflective rear inside surface 10 of stationary base member 4 by U-shaped mounting brackets 82 , and an electric cord 22 with and on-off switch 26 connected through stationary base member 4 for activation of multiple lights 18 . What FIG. 5 shows being different from other illustrated embodiments of the present invention is a hooked display object support device 52 and cord 54 adapted for suspending a display object 24 within the interior space, and one suspended display object 24 connected to the hooked display support device 52 via cord 54 .
In contrast, FIGS. 6–8 shows different means for supporting a display object 24 at elevation within the interior chamber defined by stationary base member 4 and cover 6 . FIG. 6 shows a fifth preferred embodiment 58 of the present invention having a rectangular housing with a hinged front cover 6 made from a partially reflective surface 8 supported by a frame, with cover 6 being in its fully closed position, a rearwardly positioned fully reflective surface 10 , and three display objects 24 positioned between cover 6 and fully reflective surface 10 , one of the display objects 24 being positioned upon a movable support member 40 placed on the bottom interior surface of the housing, with two additional display objects 24 each being positioned upon a movable support member 40 , with one of the movable support members 40 being attached to the partially reflective surface 8 by suction cup means 60 and the other movable support member 40 being attached with bonding means 62 to partially reflective surface 8 . FIG. 7 shows a sixth preferred embodiment 64 of the present invention from its side and having a housing with a box-like stationary base member 4 and a fully reflective rear inside surface 10 with its reflective side against the rear inside surface of stationary base member 4 , a substantially planar cover 6 closed against stationary base member 4 and comprising a partially reflective surface 8 supported by a frame, a display support 34 having a transparent or translucent upper surface 38 positioned in the bottom part of stationary base member 4 , a light source 32 positioned under display support 34 , a display object 24 positioned on top of a movable support member 40 placed centrally upon the display support 34 , and a vertically extending mounting strip 70 on the wall of the housing behind the display object 24 with holes 68 therein for adjustable positioning of elevated support members 84 (shown in FIG. 8 ) having complementary protrusions 88 for the optional elevated display of additional objects between stationary base member 4 and cover 6 via mounting strip 70 . FIG. 8 shows a front view of a seventh preferred embodiment 72 of the present invention having a housing with a box-like stationary base member 4 and a fully reflective rear inside surface 10 , a substantially planar cover 6 attached with hinge 12 to one side of stationary base member 4 and comprising a frameless partially reflective surface 8 supported by a frame, two-part closure means 30 A and 30 B for securely positioning cover 6 against stationary base member 4 when cover 6 is in its fully closed position, multiple lights 18 positioned within the interior space defined by stationary base member 4 and cover 6 , three display objects 24 positioned between cover 6 and the fully reflective surface 10 , two opposed sets of vertically extending peg holes 68 formed in the sides of stationary base member 4 with each set being on a different side of the display objects 24 and adapted for adjustable positioning of elevated support members 84 at different heights within the interior space, with one of the display objects 24 being positioned upon a movable support member 40 placed on the bottom interior surface of the housing, and a second display object 24 being positioned upon an elevated support member 84 attached to two peg holes 68 on one side of stationary base member 4 , and a third display object 24 positioned upon an elevated support member 84 having protrusions 88 and ready for connection to peg holes 68 on the opposed side of stationary base member 4 .
FIG. 9 shows an eighth preferred embodiment 74 of the present invention having a hexagon-shaped housing with a substantially planar platform-like stationary base member 4 and a display support 34 with a transparent or translucent upper surface 38 positioned above stationary base member 4 . FIG. 9 also shows eighth preferred embodiment 74 having a display object 24 being maintained in its designated display position by a hexagon-shaped movable support member 78 centrally upon upper surface 38 . Miniature lights 18 are positioned under the perimeter of upper surface 38 and secured thereto by six U-shaped mounting brackets 82 . The number of U-shaped mounting brackets 82 used is not critical, however it must be sufficient to maintain miniature lights 18 close to upper surface 38 to provide adequate illumination for display object 24 and creation of a pleasing infinity display effect. In the alternative, a light source 32 , such as is shown in FIG. 10 , could be used to illuminate display object 24 . FIG. 9 also shows a box-like cover 76 poised over display object 24 and display support 34 , that can be vertically lifted from stationary base member 4 to give access to the interior space defined by stationary base member 4 and cover 76 for the exchange of display object 24 . In FIG. 9 cover 76 is shown comprising adjoining frameless partially reflective surfaces 8 , which can include but are not limited to mirrors. Therefore, in the description of the present invention herein, the word mirror can be substituted for reflective surface, and the reverse. As a result, when first preferred embodiment 74 is table mounted, the infinity mirror display effect created with display object 24 can be viewed from a fully 360°. FIG. 9 also shows electrical cord 22 extending from the lower back surface of stationary base member 4 and on-off switch 26 in its preferred location close to stationary base member 4 . For illustrative purposes, electrical cord 22 is shown in a shortened condition. Although not shown, it is contemplated in first preferred embodiment 74 for display objects 24 to be positioned for viewing upon elevated movable support members 84 secured by pegs holes 68 in mounting strips 70 , or in the alternative upon movable support members 40 attached to the interior surfaces of one or more partially reflective surfaces 8 in cover 76 at differing heights by adhesive/bonding agents 62 , as well as movable support members 40 secured directly to the interior surfaces of one or more partially reflective surface in cover 76 by suction cups 60 or adhesive/bonding agents 62 , and suspension from filamentous materials 54 attached to anchoring devices 52 that are directly connected to the interior surface of one or more partially reflective surfaces in cover 76 . Although box-like cover 76 , display support 34 , and platform-like stationary base member 4 are shown in FIG. 1 to have hexagonal configurations, the first preferred embodiment is not limited to hexagon-shaped configurations, and it is also contemplated for cover 76 , display support 34 , and stationary base member 4 to have other angular configurations, such as but not limited to octagonal, trapezoidal, and square. Also, FIG. 9 shows stationary base member 4 extending beyond display support 34 so that when cover 76 is placed in its closed position, cover 76 is positioned against stationary base member 4 and does not come in contact with the table, counter, or floor surface (not shown) positioned beneath stationary base member 4 .
FIG. 10 shows a ninth preferred embodiment 80 of the present invention having a rectangular housing with a substantially planar platform-like stationary base member 4 and a light source 32 attached through the upper surface of stationary base member 4 . FIG. 10 also shows ninth preferred embodiment 84 having a display support 34 with a transparent or translucent upper surface 38 poised above stationary base member 4 , a display object 24 being retained in a fixed display position by a movable support member 40 centrally upon upper surface 38 , and a box-like cover 76 that is vertically lifted from stationary base member 4 to give access to the interior space defined by stationary base member 4 and cover 76 . In FIG. 10 cover 76 is poised over stationary base member 4 in an open position allowing for rapid exchange of display object 24 . Also, the cover 76 shown in FIG. 10 comprises adjoining partially reflective surfaces 8 each supported by a frame and appearing like the cover 6 shown in FIGS. 1–3 and FIG. 6 . FIG. 10 also shows electrical cord 22 extending from the lower back surface of stationary base member 4 and on-off switch 26 in its preferred location close to stationary base member 4 . For illustrative purposes, electrical cord 22 is shown in a shortened condition. In FIG. 10 , if stationary base member 4 is not configured to extend beyond display support 34 , when cover 76 is placed in its closed position against stationary base member 4 , stationary base member 4 would be positioned within cover 76 and cover 6 would come in contact with the table, counter, or floor surface (not shown) positioned beneath stationary base member 4 . In such a position, although not shown, cover 76 would have a small aperture or cut-out for electrical cord 22 . Display support 34 could be freely separable from stationary base member 4 , or permanently secured thereto. When display support 34 is permanently secured to stationary base member 4 , light source 32 would be exchanged through the bottom surface of stationary base member 4 . Although it is contemplated for cover 76 , display support 34 , stationary base member 4 , movable support members 40 to have any type of angular configuration, angular configurations are preferred since arcuate configurations do not always provide as pleasing an infinity mirror display effect. Also, no handle is contemplated for cover 76 in the ninth preferred embodiment 84 to assist in lifting it away from stationary base member 4 , as handles often detract from the infinity mirror display effect created by display objects 24 positioned within the interior space defined between cover 76 and stationary base member 4 .
FIG. 11 shows a tenth preferred embodiment 90 of the present invention having a rectangular housing with a totally reflective rear surface 10 and a front surface having a partially reflective surface 8 , and two sides each having a partially reflective surface 8 ′, as well as a light source 32 attached through the top end of stationary base member 4 , which also serves as cover 6 and can be vertically lifted away from stationary base member 4 , as shown by the upwardly directed arrow adjacent to the front left corner of cover 6 , so as to give access to the interior space defined by stationary base member 4 and cover 6 for the exchange of display objects 24 Although cover 6 is shown as opaque, it could alternatively comprise a partially reflective surface 8 . Also, totally reflective rear surface 10 could be replaced by a partially reflective surface 8 . The number, relative positioning through the top end of stationary base member 4 , type of lighting used, and configuration of light sources 32 are not critical, and one or more top mounted light sources 32 may be used, and may even be used in combination with light sources 32 and multiple lights 18 used within the interior space between stationary base member 4 and cover 6 , as long as the total amount of light produced is adequate for an effective infinity mirror display effect. FIG. 11 also shows a display object 24 being supported atop a movable display support 40 and multiple images 42 extending rearwardly therefrom. In addition, FIG. 11 shows other reflected images 42 in broken lines, which indicates the diminished clarity and brilliant of reflected images 42 that typically are the result of a multiple reflective process occurring between several reflective and partially reflective surfaces 10 , 8 , and 8 ′. Further, if cover 6 is not made from a partially reflective material 8 , it can have an interior surface that is totally reflective 10 for enhanced illumination of display objects 24 used to create an infinity display effect. When overhead illumination of display objects is used and the display objects are viewed from a partially reflective surface 8 in perpendicular orientation to top cover 6 , the infinity display effect can be viewed while cover 6 is in an opened position, although when cover 6 also contains the source of illumination 32 , as cover 6 is increasingly opened, the brilliance infinity display effect and quantity of reflected images 42 are diminished. Also, when the partially reflective surface 8 through which an observer (not shown) views display objects 24 is minimally reflective or transparent, an infinity display effect can still be seen when partially reflective surfaces 8 ′ are laterally positioned relative to the minimally reflective or transparent viewing surface.
FIG. 12 shows an eleventh preferred embodiment 94 of the present invention having a rectangular housing and a multi-sided cover 96 that separates from the stationary base member 4 to give temporary access to the interior space defined by stationary base member 4 and cover 6 between infinity display uses. The cover 96 can be attached by hinges 36 , or secured to the base member via quick-release fasteners 30 A and 30 B. Since the infinity display effect requires a minimum of two reflective surfaces 10 or 8 , with at least one being partially reflective, FIG. 12 shows cover 96 comprising two partially reflective surfaces 8 centrally supported within a frame to complement the totally reflective surface 10 attached to the back interior surface of stationary base member 4 for infinity display effect purposes. FIG. 12 also shows the non-movable side of base member 4 having a partially reflective surface 8 . Cover 6 would not need to be totally closed against stationary base member 4 for viewing an infinity display effect through partially reflective surface 8 , however, the number of repeated images in the infinity display effect decreases as hinged cover 96 is rotated away from totally reflective surface 10 . Although not shown in FIG. 12 , it is preferred for each partially reflective surface 8 to be held securely within the frame of cover 6 by a minimum of four angular S-shaped mounting brackets 86 , each in contact with partially reflective surface 8 and the frame of cover 6 near to their respective corners. However, although it is contemplated for angular S-shaped mounting brackets 86 to be used in first preferred embodiment 2 , the use of angular S-shaped mounting brackets 86 is not critical, and it is considered within the scope of the present invention for other types and configurations of commonly used mirror-to-frame mounting brackets to be employed. Since cover 6 is easily opened without disturbing stationary base member 4 , display objects 24 would not need to be permanently secured or anchored within stationary base member 4 , during their use in providing an infinity display effect. Although not shown, variations of the eleventh embodiment also considered within the scope of the present invention could include either the left or right side of stationary base member 4 , or both, containing partially reflective surfaces 8 , cover 6 containing more than one partially reflective surfaces 8 , the top surface of stationary base member 4 containing a partially reflective surface 8 , and even the back surface of stationary base member 4 containing a partially reflective surface 8 in place of totally reflective surface 10 , particularly when a bottom or top positioned source of light is used instead of a strand of multiple miniature lights 18 . Further, although not shown, a handle could optionally be attached to cover 96 anywhere along the distal edge of the frame of cover 96 in a position remote from hinges 36 . However, generally a handle is not preferred and instead cover 96 can be made to slightly overlap the perimeter of stationary base member 4 , at least on the perimeter edge of the frame of cover 96 that is remote from hinges 36 , so as to provide an easily gripped hand-hold for manipulating cover 6 between its fully closed position and its fully open position. Although it is preferred for electrical cord 22 to extend through a small opening in the back surface of stationary base member 4 near to its bottom surface, and for on-off switch 26 to be conveniently positioned close to stationary base member 4 for easy access thereto, such connections are not critical. Further, although on-off switch 26 is shown to have a rotating disk type of switch activation means for aesthetic purposes, it is considered to be within the scope of the present invention, although not shown, for on-off switch 26 to also have a toggle, depressible button, rotatable knob, or other type of electrical activation means. | An infinity mirror display apparatus, and method of manufacture, which allows private and commercial users to rapidly trade out favored display objects to create different infinity display effects for continued viewer interest and enjoyment. The apparatus comprises a housing having a stationary base member and an easily removable cover which together define an enclosed interior space, at least two reflective surfaces positioned adjacent to the interior space with at least one of the surfaces being partially reflective, and at least one illumination source communicating with the interior space. The cover can be partially or totally removed from the stationary member during display object exchange. The apparatus can be wall-mounted for front and/or side viewing of the infinity mirror effect, or it can be table-mounted with multiple partially reflective surfaces for a full 360° view of the infinity mirror effect created by one or more illuminated display objects. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of application Ser. No. 593,890, filed July 7, 1975 abandoned which is a continuation-in-part of application Ser. No. 427,183, filed Dec. 21, 1973 abandoned, which application is a continuation of application Ser. No. 11,826, filed Feb. 16, 1970, now U.S. Pat. No. 3,847,898, which application is a continuation-in-part of application Ser. No. 828,380, filed May 27, 1969, now abandoned.
In application Ser. No. 745,096, now U.S. Pat. No. 3,547,905 issued Dec. 15, 1970, there is disclosed 1-β-D-arabinofuranosylcytosine 5'-(1-adamantanecarboxylate), described as possessing sustained release properties and a "depot" effect. The compound was synthesized by direct adamantoylation of ara-cytidine to form first the bis-adamantoyl compound, and then selective hydrolysis gave the 5'-O-adamantoyl ester.
BACKGROUND OF THE INVENTION
Ara-cytidine, also called cytarabine, cytosine arabinoside, or CA, has been known for some time as an effective agent for controlling growth of certain kinds of cancers, especially leukemia. Its use has been hampered, however, because of difficulties in establishing and maintaining effective and sustained contact between the compound and the cells under treatment.
BRIEF DESCRIPTION OF THE INVENTION
The 5'-O-derivatives, including principally esters, of this invention are prepared by first blocking or protecting the primary amino nitrogen or ara-cytidine with β,β,β-trihaloethoxycarbonyl group wherein "halo" is chlorine or bromine, and "halide" is chloride, bromide or iodide, and then causing the blocked compound to react with an agency capable of reacting with the 5'-O-hydroxyl substituent. There result the 5'-O-derivatives of this invention. The method of this invention, which provides an effective blocking of the primary amino nitrogen, is less wasteful of esterifying agent, and being higher overall-yielding, is also less wasteful of the expensive substance, ara-cytidine. The method renders available a wide range of novel and useful 5'-O-derivatives as will be discussed below.
The compounds of this invention include salts of the 5'-O-derivatives with pharmaceutically acceptable mineral or organic acids having a pk about or less than 2.
The compounds of this invention when administered exhibit the properties characteristic of ara-cytidine, and in addition exhibit the desirable property of sustained release of ara-cytidine over periods of time after administration. Thus the modes of administration and dosages for use are those conventionally used with ara-cytidine. For example, they can be administered orally or intramuscularly. Their use intravenously is not feasible, but the need for such disadvantageous devices as the intravenous drip is obviated by the sustained release of "depot" effect of the novel compounds employing multiple injections and/or daily dosages.
In addition, the compounds of this invention exhibit antiphage properties, and, used in conjunction with a deaminase inhibitor, can be used to protect a fermentation threatened with contamination by a phage.
The ester compounds of this invention have the activities and uses that characterize the unesterified compound, cytarabine or ara-cytidine, namely, activity against acute leukemia and against lymphosarcoma, as disclosed in U.S. application Ser. No. 627,645, filed Apr. 3, 1967, now U.S. Pat. No. 3,444,294. As in the case of ara-cytidine sterile injectable solutions such as in cottonseed oil, peanut oil, and sesame seed oil, or dispersions or sterile non-aqueous solutions or dispersions in water, aqueous saline dispersions suited for injectable use, or sterile powers suited for extemporaneous preparation of sterile injectable solutions or dispersions can be prepared, using the ester compound of this invention. Such solutions are prepared by incorporating the ester compound in the solvent or dispersion medium together with appropriate particle coating agents, surfactants, antibacterial or antifungal agents, isotonic agents and the like. Powders can be prepared by freeze-drying such an appropriately prepared solution or dispersion. Dosage unit forms such as vials and ampules are feasible. The dosage depends on age, weight, and severity of condition of the subject, route and frequency of administration, and can vary from 0.1 to about 50 mgs./kg., or a daily total dose of about 3 to about 4000 mgs., given singly or in divided doses. A unit dosage can contain the ester compound of this invention from about 3 to about 1000 mgs. per unit. This can be from about 0.5% to 25% w/v of the total composition. Utilizing the sustained release characteristic of the ester compounds of this invention, unit doses can be prepared and administered intramuscularly in amounts varying from about 0.5 to about 10 grams or more. The amount of ester compound in such dosage can vary up to that indicated as sufficient to aid regression and palliation of the leukemia. Thus a 50 mg./kg dosage can be given once weekly in a single or multiple sites or doses which can be larger can be administered at wider spaced time intervals.
For oral administration, either solid or fluid unit dosage forms can be prepared. For preparing solid compositions such as tablets, the principal active ingredient is mixed with conventional ingredients such as talc, magnesium stearate, dicalcium phosphate, magnesium aluminum silicate, calcium sulfate, starch, lactose, acacia, methylcellulose, and functionally similar materials as pharmaceutical diluents or carriers. Wafers are prepared in the same manner as tablets, differing only in shape and the inclusion of sucrose or other sweetener and flavor. In their simplest embodiment, capsules, like tablets, are prepared by mixing the active compound of the formulation with an inert pharmaceutical diluent and filling the mixture into a hard gelatin capsule of appropriate size. In another embodiment, capsules are prepared by filling hard gelatin capsules with polymer coated beads containing the active compound. Soft gelatin capsules are prepared by machine encapsulation of a slurry of the active compound with an acceptable vegetable oil, light liquid petrolatum or other inert oil.
Fluid unit dosage forms for oral administration such as syrups, elixirs, and suspensions can also be prepared. The water-soluble forms of the active compound can be dissolved in an aqueous vehicle together with sugar, aromatic flavoring agents and preservatives to form a syrup. An elixir is prepared by using a hydro-alcoholic (ethanol) vehicle with suitable sweeteners such as sucrose together with an aromatic flavoring agent. Suspensions can be prepared of the insoluble forms with a syrup vehicle with the aid of a suspending agent such as acacia, tragacanth, methylcellulose and the like.
The process of this invention is generally one of esterification and may be shown illustratively in the following reactions wherein X is chloro or bromo: ##STR1##
In the above reaction, variations can be made in a number of the stages. For example, the intermediate compound: ##STR2## can be made by reaction of 5'-O-trityl-ara-cytidine with β,β,β-trihaloethoxycarbonyl halide to form the analogous N-derivative, and subsequently removing the trityl group by known methods.
The reaction is given illustratively as follows: ##STR3##
5'-O-Trityl ara-cytidine can be used as starting material for the following alternative reactions in which an excess of β,β,β-trichloroethoxycarbonyl chloride is used: ##STR4##
In practicing the invention, and as is disclosed in more detail in the foregoing and ensuing description, the process involves use of a novel class of intermediates having the following structural formula: ##STR5## in which y=H, trityl or an acyl radical. These intermediates, where y=H are capable of being transformed into the wide class of esters disclosed in this application, protected as shown at the amino nitrogen. The esters, too, are intermediates and constitute the compounds of the above formula where y=acyl. These ester intermediates are further capable of being transformed by removal of the protective group on the amino nitrogen into the free amino ester product compounds possessing the aforesaid valuable pharmacological properties, as will be seen from the following description and examples.
Alternatively, the primary amino group of ara-cytidine may be protected from concomitant acylation by protonation. This is done by reacting ara-cytidine with the acylating agent, for example, an acyl halide or acyl anhydride in the presence of a sufficiently high hydrogen ion concentration, so that the primary amino group of ara-cytidine is protected. It has been found in this invention that the amino group in such amino protected nucleoside species is resistant to conventional acylation procedures.
In the above equations, of particular value and interest in the general sense are those in which the substituent acyl is that of an organic carboxylic acid, ##STR6## in which R can have a wide range of values. For example, R can broadly mean a straight- or branched-chain aliphatic radical containing from 1 to 20 carbon atoms which can be substituted by halogen, hydroxyl, carboxyl or mercapto groups, a monocyclic or bicyclic aromatic radical of from 6 to 10 carbon atoms, on a cage-type hydrocarbon radical containing from 7 to 20 carbon atoms. R can also denote the variety of substituents that are shown in Table I to XI which follow.
Representative values of R in the foregoing are: methyl, ethyl, t-butyl, 2,2-dimethylpropyl, 1-chloro-2,3-dimethylbutyl, 2,2-dimethylpropyl, 1-mercapto-2,2-dimethylpropyl, phenyl, 2-methylphenyl, 2,6-dimethylphenyl, 2,4,6-trimethylphenyl, 1-naphthyl, 2-naphthyl, ##STR7## and also groups, which, together with the ##STR8## group make up the acyl group of acids such as glutamic, glutaric, succinic, fumaric, aconitic, itaconic, levulinic, 3,3-dimethylglutaric and other 3,3-dialkylglutaric acids and other acids as will be exemplified later.
Of these, of particular application are the classes of N-protected intermediates wherein ##STR9## in which R' 1 is an aliphatic radical of from 1 to 20 carbon atoms, an aromatic radical of from 6 to 10 carbon atoms, a cage-type hydrocarbon radical of from 7 to 20 carbon atoms, a monocyclic aliphatic radical of from 4 to 10 carbon atoms, an araliphatic radical of from 7 to 12 carbon atoms or a monocyclic heterocyclic radical of from 4 to 10 carbon atoms or wherein ##STR10## is the acyl radical of an aliphatic dicarboxylic acid of from 3 to 8 carbon atoms. Eliminative removal of the amino-protecting group results in the free amino ester product compound corresponding otherwise to the formula immediately above but wherein ##STR11## wherein R 1 is a radical selected from the group consisting of an aliphatic of from 1 to 20 carbon atoms, aromatic of from 6 to 10 carbon atoms, a monocyclic aliphatic of from 4 to 10 carbon atoms, and araliphatic of from 7 to 12 carbon atoms or a monocyclic heterocyclic of from 4 to 10 carbon atoms; or wherein ##STR12## is the acyl radical of an aliphatic dicarboxylic acid of 3 to 8 carbon atoms.
One important class of such novel compounds is that wherein the acylating agent used is an acyl halide or an anhydride of an aliphatic acid containing 1 to 18 carbon atoms, such as acetyl chloride or anhydride, isobutyrylbromide or anhydride, caproyl chloride or anhydride, palmityl chloride or anhydride, stearyl chloride or anhydride, lauroyl chloride or anhydride, oleyl chloride or anhydride, myristic chloride or anhydride, isomers thereof and the like.
Another important class of novel compounds of this invention is that wherein the acyl radical of ##STR13## is that of a dicarboxylic aliphatic acid of from 3 to 8 carbon atoms, such as glutaric, 3,3-dialkylglutaric, succinic, itaconic, or fumaric acid, and the like.
In addition to the above, R can also be a substituted amino group in which the substituents can be aliphatic, aromatic, heterocyclic or cage-type radical, as illustrated later. R can also be a mercapto group or an alkylmercapto group, MS- in which M is as illustrated later. The acyl substituent at 5'-O can also be those to form a carbonate ester as illustrated later.
In addition to carboxyl acyl groups the derivative groups attached to the 5'-O oxygen of ara-cytidine can be thio-acyl group such as ##STR14## in which M 1 , A 1 and B 1 , R 2 and R 3 are as will be illustrated later.
The acyl group attached to the 5'-oxygen of ara-cytidine can also be that of an esterified phosphoric acid such as ##STR15## in which the value of R 4 and R 5 can be an aliphatic or substituted aliphatic as will be illustrated later; ##STR16## in which the value of A 2 and B 2 can be hydrogen or aliphatic as will be illustrated later, or ##STR17## in which the value of A 2 and B 2 is as given above.
The processes of this invention as described above render possible the preparation of a wide variety of 5'-O-esters of ara-cytidine. Among these products are a number of classes of novel compounds, heretofore unknown, in their free base or salt form which possess as a common property, the advantage of sustained release previously described.
DETAILED DESCRIPTION OF THE INVENTION
In the following tables there are set forth the acylating agents together with the substituent groups of the acylating agents referred to above and the identification of the product ester of ara-cytidine. These agents are reacted with ara-cytidine protected as described above, and in each case the intermediate product containing the N 4 -trihaloethoxycarbonyl protective group is formed, which group is subsequently removed as described above and in the examples which follow.
A number of acylating agents containing the trichloroethoxycarbonyl group as a substituent are given illustratively in the tables. It is to be understood that such substituted acylating agents can be prepared by reaction with trichloroethoxycarbonyl chloride as described above (for ara-cytidine and related compounds) and as illustrated in the following examples. The trichloroethoxycarbonyl groups of such 5'-O-acyl radicals are removed along with the trihaloethoxycarbonyl group protecting the amino group of ara-cytidine in the final eliminative step of the process.
The acid chlorides of the carboxylic acids, used as acylating agents, can be prepared by conventional methods, as for example, by reaction of the acid RCOOH (a) with SOCl 2 (b) with PCl 5 , or (c) with POCl 3 . The method (a) is suitable for most acids except those which boil within 5°-10° C. of SOCl 2 , in which case, the method (c) is suitable.
It is further to be understood that the acid RCOOH can be transformed to an active acylating agency by first reacting it with p-toluenesulfonyl chloride, and this reaction product (tosylate) can be used in place of the anhydride or chloride, in accordance with the procedures described in J. Am. Chem. Soc. 77, 6214 (1955).
Analogous to the above acid RCOOH can be transformed to an acylating agency by first reacting it with (CF 3 CO) 2 O, and then using the product as acylating agent, in accordance with the procedures described in Chem. Rev. 55, 787 (1955).
A further esterification procedure which is suitable is to use the acid RCOOH directly, carrying out the reaction in the presence of dicyclohexylcarbodiimide, in accordance with the procedures described in Compt. Rend. 252, 896 (1961); Ibid. 255, 945 (1962); J. Org. Chem, 27, 4075 (1962) and Tetrahedron 21, 3531 (1965).
For acylation of ara-cytidine only at the 5'-O position, according to this invention, coincident acylation of the amino group at position 4 must be prevented. This is done by first protecting the amino group by a suitable protective agent. In one form of the invention process, this is accomplished by reacting ara-cytidine with a trihaloethoxycarbonyl halide, in which "halo" is chlorine or bromine, and "halide" is chloride, bromide or iodide. Exemplary reagents are trichloroethoxycarbonyl chloride (Aldrich Chemical Co., Milwaukee, Wisconsin) and tribromoethoxycarbonyl chloride J. Org. Chem. 33, 3589-93 (1968)!.
When ara-cytidine is reacted with the appropriate molar proportion (about 2) of trihaloethoxycarbonyl halide, the intermediate product N 4 , 5'-O-bis-trihaloethoxycarbonyl ara-cytidine is formed. This reaction is previously shown. The reaction can be carried out in pyridine, and the product recovered by removal of the solvent by distillation. The reaction conditions for protective group removal described in Example 1 can be followed.
The N 4 , 5'-O-bis-trihaloethoxycarbonyl ara-cytidine can be hydrolyzed by treatment with dilute sodium hydroxide. The compound dissolved in tetrahydrofuran is treated with an equal volume of sodium hydroxide solution, about 0.3 N, let stand at room temperature to equilibrate, and then is neutralized with acetic acid. The product, N 4 -trihaloethoxycarbonyl ara-cytidine, can be recovered by crystallization and purified by recrystallization from acetone.
Advantageously, N 4 -trihaloethoxycarbonyl ara-cytidine can be prepared by reacting 5'-O-trityl ara-cytidine (U.S. Pat. No. 3,338,882, Example 1) with N 4 -trihaloethoxycarbonyl halide (THEC halide) (Example 1). The reaction is conducted in dry pyridine at low temperature, about -5° to 5°, preferably about 3° C. If the molar proportion of 5'-O-trityl ara-cytidine to THEC halide is about 1:1, the reaction product is N 4 -trihaloethoxycarbonyl-5'-O-trityl-ara-cytidine. If an excess of THEC halide is used, i.e., a molar proportion less than 1:3, preferably about 1:4 to 1:5, the reaction product is N 4 -2',3'-O-tris-trihaloethoxycarbonyl-5'-O-trityl-ara-cytidine. The solvent is removed and the residue is extracted into a chlorinated hydrocarbon solvent, e.g., methylene chloride, and washed with water. In the case where the reaction product is tris-trihaloethoxycarbonyl-5'-O-trityl-ara-cytidine, the protective group at 2'-O and 3'-O can be removed at this point, if desired, by hydrolysis with a base, e.g., 0.15 N sodium hydroxide in 50% tetrahydrofuran-50% water, to give the N 4 -monoprotected 5'-O-trityl product which is isolated. Alternatively, the washed residue in a chlorinated hydrocarbon solvent is evaporated. If desired, the THEC-protected, tritylated products can be recrystallized from suitable solvents, e.g., methylene chloride or acetone. The protected intermediates, mono- or tris-THEC 5'-O-trityl CA derivatives, are treated with 80% acetic acid as illustrated in Example 2 to remove the 5'-O-trityl group to yield the intermediate, N 4 -trihaloethoxycarbonyl ara-cytidine.
By acylation at the 5'-O position by use of the acylating agents exemplified by Tables I to XI and illustrated in the examples, there are produced the novel amino protected 5'-esters of ara-cytidine of the invention. The protective group is removable by treatment with metallic zinc in methanol solution of the ester; by treatment with metallic zinc, for example as zinc dust, and acetic acid, for example, in 80 to 90% acetic acid solution; or by treatment with zinc chloride or zinc acetate in methanol.
The water solubility of the 5'-O-derivatives of this invention can be improved and thus their pharmaceutical versatility is enhanced by conversion to their salt form with pharmaceutically accepted acids which have a pk about or less than 2. These acids can be broadly classed as the strong mineral or organic acids, and this class of acids are appropriate because ara-cytidine and the 5'-O-derivatives of it which characterizes this invention are weak bases. Examples of the strong acids are hydrochloric, sulfuric, phosphoric, glutaric, glutamic, tartaric, trihydroxybenzoic, formic and the like. They are formed by suspending the desired 5'-O-derivatives in a medium such as methanol and adding appropriately one equivalent of the desired acid. The result is a solution of the acid salt, which can be caused to separate by the adding of appropriate media such as diethyl ether. The salts can be purified by recrystallization from solvent mixtures such as methanol:ether. The hydrohalide salt can also be obtained by simply not neutralizing the acrylation mixture resulting from the reaction of RCOCl before isolating the acylated product from the solvent.
In Table I, below, are given, illustratively, typical acylating agents and resulting ara-cytidine-5'-O-acylate products for the case when the acyl group is ##STR18## wherein R 1 is as defined previously.
TABLE 1__________________________________________________________________________R of RCOR.sub.1 AcylatingNo. R.sub.1 Agent Product__________________________________________________________________________ 1 CH.sub.3 Acetic anhydride or acetyl 5'-O-acetyl ara- chloride cytidine 2 (CH.sub.3).sub.3 C Pivaloyl chloride 5'-O-pivaloyl ara- cytidine 3 (CH.sub.3).sub.2 CH Isobutyryl chloride 5'-O-isobutyryl 4 (CH.sub.3 CH.sub.2).sub.7 Octanoyl chloride 5'-O-octanoyl ara- (caproyl chloride) cytidine 5 CH.sub.3 (CH.sub.2).sub.14 Palmityl chloride 5'-O-palmitylara- cytidine 6 CH.sub.3 (CH.sub.2).sub.16 Stearyl chloride 5'-O-stearyl ara- cytidine 7 CH.sub.3 (CH.sub.2).sub.7 CHCH(CH.sub.2).sub.7 Oleyl chloride 5'-O-oleyl ara- cytidine 8##STR19## β-chloropivaloyl chloride 5'-O-(β-chloropi- valoyl) ara- cytidine 9##STR20## p-nitrobenzoyl chloride 5'-O-p-nitroben- zoyl ara-cytidine10##STR21## o-toluoyl chloride 5'-O-toluoyl ara- cytidine11##STR22## Benzoyl chloride 5'-O-benzoyl ara- cytidine12##STR23## 2,6-dimethylbenzoyl chloride 5'-O-(2,6-dimethyl- benzoyl) ara- cytidine13##STR24## 2,4,6-trimethylbenzoyl chloride 5'-O-(2,4,6-tri- methylbenzoyl) ara-cytidine14##STR25## 1-fluorene carbonyl chloride 5'-O-(1-fluorene carbonyl)ara- cytidine15##STR26## 9-fluorene carbonyl chloride 5'-O-(9-fluorene carbonyl)ara- cytidine16##STR27## 1-naphthoyl chloride 5'-O-(1-naphthoyl) ara-cytidine17##STR28## 1-indene-carbonyl chloride 5'-O-1-indene-car- bonylara-cytidin e18##STR29## p-anisoyl-chloride 5'-O-p-anisoyl ara- cytidine19##STR30## 3,4,5-trimethoxybenzoyl chloride 5'-O-(3,4,5-tri- methoxybenzoyl)ara - cytidine20##STR31## p-toluoyl chloride 5'-O-p-toluoyl ara- cytidine21##STR32## 1-norbornanecarbonyl chloride 1-norbornylcarbonyl ara-cytidine22##STR33## exo- or exo/endo-mixture of 2-norbornanecarbonyl chlo- ride exo- or exo/endo- mixture of 5'-O- 2-norbornylcar- bonyl) ara-cytidine23##STR34## 7-norbornane carbonyl chlo- ride 5'-O-(7-norbornyl- carbonyl)ara- cytidine24##STR35## 2-adamantane carbonyl chloride 5'-O-2-adamantyl- carbonyl ara- cytidine25##STR36## 1-adamantyl acetyl chloride 5'-O-(1-adamantyl acetyl) ara- cytidine26##STR37## α-chloro-3,5,7-trimethyl- 1-adamantyl acetyl!chlo- ride 5'-O- (α-chloro- 3,5,7-trimet hyl-1- adamantyl)acetyl! ara-ctyidi ne27##STR38## pentacyclo 4 . 2 . O . O.sup.2,5 . O.sup.3,8 . O.sup.4,7 !octane carbonyl chloride (cubane carbonyl chloride) 5'-O-pentacyclo- 4 . 3 . O . O.sup.2,5 . O.sup.3,8 . O.sup.4,7 !octyl- carbonyl ara- cytidine28##STR39## cyclobutane carboxylic acid anhydride 5'-O-cyclobutyl- carbonyl ara- cytidine29##STR40## cyclopentane carbonyl chloride 5'-O-cyclopentyl- carbonyl ara- cytidine30##STR41## cyclohexane carbonyl chloride 5'-O-cyclohexyl- carbonyl ara- cytidine31##STR42## picolinyl chloride 5'-O-picolinyl ara-cytidine32##STR43## tetrahydrofuroyl chloride (tetrahydropyromuconyl chloride) 5'-O-tetrahydro-2- furoyl ara- cytidine33##STR44## 9-xanthene carbonyl chloride 5'-O-(9-xanthenyl- carbonyl) ara- cytidine34##STR45## nicotinyl chloride 5'-O-nicotinoyl ara-cytidine35##STR46## 6-methoxy-4-quinoline carbonyl chloride (quininyl chloride) 5'-O-(6-methoxy-4- quinolylcarbonyl ) ara-cytidine36##STR47## 4-cinnoline carbonyl chloride 5'-O-(4-cinnolyl- carbonyl)ara- cytidine37##STR48## 2-thiophene carbonyl chloride 5'-O-(2-thenoyl)ara- cytidine38##STR49## 4-thianaphthene acetyl chloride 5'-O-(4-thianaph- thene acetyl)ara- cytidine39##STR50## 2-furoyl chloride 5'-O-2-furoyl ara- cytidine40##STR51## 5-bromo-2-furoyl chloride 5'-O-(5-bromo-2- furoyl)ara- cytidine41##STR52## coumalyl chloride 5'-O-coumalyl ara cytidine42##STR53## coumarin-3-carbonyl chloride 5'-O-coumarin-3- carbonyl ara- cytidine43##STR54## isonicotinoyl chloride 5'-O-isonicotinoyl ara-cytidine44##STR55## 2-quinuclidine carbonyl chloride 5'-O-(2-quinuclidi- nylcarbonyl)ara - cytidine45##STR56## 3-quinuclidine carbonyl chloride 5'-O-(3-quinuclidi- nylcarbonyl) ara- cytidine46##STR57## 4-quinuclidine carbonyl chloride 5'-O-(4-quinuclidi- nylcarbonyl) ara- cytidine47##STR58## N-trichloroethoxycarbonyl- 2-pyrrole carbonyl chloride 5'-O-(2-pyrrolylcar- bonyl) ara-cytidine48##STR59## N-trichloroethoxycarbonyl- 2-indole carbonyl chloride 5'-O-(2-indolylcar- bonyl) ara-cytidine49##STR60## N-trichloroethoxycarbonyl- 3-indole carbonyl chloride 5'-O-(3-indolylcar- bonyl) ara-cytidine50##STR61## hydroxybenzoyl chloride trichlorocarbonate 5'-O-hydroxyben- zoyl ara-cytidine51##STR62## trans-3-(n-propyl)-hygric acid chloride, hydrochloride 5'-O-trans- 3-(n- propyl)hygroyl!- ra-cytidine52 HOOCCH.sub.2 CH.sub.2 succinic anhydride 5'-O-hemisuccinyl ara-cytidine53##STR63## fumaryl chloride 5'-O-hemifumaryl ara-cytidine54##STR64## 3,3-dimethylglutaric anhydride 5'-O-hemi(3,3-di- methylglutaryl) ara-cytidine55##STR65## itaconic anhydride 5'-O-itaconyl ara- cytidine56##STR66## aconitic anhydride 5'-O-aconityl ara- cytidine__________________________________________________________________________ *TCEC means the trichloroethoxycarbonyl radical.
In Table II, below, are given typical acylating agents and resulting products in the case when the acyl group is ##STR67##
TABLE II__________________________________________________________________________A B Acylating Agent Final Product__________________________________________________________________________H H N-carbonylsulfamic acid 5'-O-(carbamoyl)-ara-cytidine chloride, sodium cyanide and trifluoro-acetic acidH CH.sub.3 CH.sub.2 ethyl isocyanate 5'-O-(ethylcarbamoyl)-ara- cytidine ##STR68## cyclohexyl isocyanate 5'-O-(cyclohexylcarbamoyl)- ara-cytidineH CH.sub.3 (CH.sub.2).sub.7 n-octyl isocyanate 5'-O-(n-octylcarbamoyl)- ara-cytidineC.sub.2 H.sub.5 C.sub.2 H.sub.5 diethylamine and 5'-O-(diethylcarbamoyl)ara- phosgene cytidinen-C.sub.4 H.sub.9 n-C.sub.4 H.sub.9 di-n-butylamine and 5'-O-(di-n-butylcarbamoyl)- phosgene ara-cytidineCH.sub.2CHCH.sub.2 ##STR69## N-allylaniline and phosgene 5'-O-(N-allyl-N-phenylcar- bamoyl)-ara-cyti dine ##STR70## pipyridine + phos- gene 5'-O-(N,N-pentamethylene- carbamoyl)-ara-cy tidine__________________________________________________________________________
In the foregoing formula, A and B are the same or different radicals selected from the group consisting of H, aliphatic of from 1 to 10 carbon atoms, monocyclic aliphatic of from 4 to 10 carbon atoms, and aromatic of from 6 to 10 carbon atoms, or in which A and B together make up an aliphatic chain of from 3 to 6 carbon atoms.
In the case where R of RCO = MS, general procedures for preparing the substituted monothiol chlorocarbonates as acylating agents are given in J. Am. Chem. Soc. 82, 4347 (1960) and Monatsch. Chem. 81, 939 (1950). Briefly the mercaptan MSH is reacted with COCl 2 in the presence of NiCl 3 to produce the acylating agent ##STR71## In this class M is a radical selected from the group consisting of aliphatic of from 1 to 10 carbon atoms, monocyclic aliphatic of from 4 to 10 carbon atoms, and aromatic of from 6 to 10 carbon atoms, and aralkyl from 7 to 12 carbon atoms. Representative acylating agents of this kind and the resulting final products are:
TABLE III__________________________________________________________________________ Mercaptan ReagentM (+COCl.sub.2) Final Product__________________________________________________________________________ ##STR72## benzyl mercaptan ara-cytidine 5'-S-benzylthiocar- bonate(CH.sub.3).sub.2 CH isopropyl mercaptan ara-cytidine 5'-S-isopropylthio- carbonateCH.sub.3 (CH.sub.2).sub.3 n-butyl mercaptan ara-cytidine 5'-S-n-butylthio- carbonateCH.sub.2CHCH.sub.2 allyl mercaptan ara-cytidine 5'-S-allylthiocar- bonate ##STR73## benzenethiol ara-cytidine 5'-S-phenylthiocar- bonate ##STR74## pentachlorothiophenol ara-cytidine 5'-S-pentachloro- phenylthiocarbonat e ##STR75## cyclohexylmercaptan ara-cytidine 5'-S-cyclohexylthio- carbonateCH.sub.3 (CH.sub.2).sub.9 n-decyl mercaptan 5'-ara-cytidine 5'-S-n-decylthio- carbonate__________________________________________________________________________
Where the acyl radical attached to the 5' oxygen of ara-cytidine is ##STR76## the acylating agent can be prepared in a manner analogous to the above, substituting thiophosgene (CSCl 2 ) for COCl 2 . In this class M 1 is a radical selected from the group consisting of aliphatic of from 1 to 10 carbon atoms, aromatic of from 6 to 10 carbon atoms, and araliphatic of from 7 to 12 carbon atoms. Representative acylating agents of this kind and the resulting final products are:
TABLE IV______________________________________ Mercaptan ReagentM.sub.1 (+CSCl.sub.1) Final Product______________________________________C.sub.2 H.sub.5 ethyl mercaptan + ara-cytidine 5'- thiophosgene S-ethyl xanthate ##STR77## phenyl thiol + thiophosgene ara-cytidine 5'- S-phenyl xanthate ##STR78## benzyl thiol + thiophosgene ara-cytidine 5'- benzyl xanthateCH.sub.3 (CH.sub.2).sub.9 decyl thiol + 5' ara-cytidine thiophosgene 5'-S-decyl xan- thate______________________________________
Where the acyl radical attached to the 5'-oxygen of ara-cytidine is ##STR79## the preparation is by the reaction of the class of products of Table IV, (i.e., where the acyl radical attached to the 5'-oxygen of ara-cytidine is ##STR80## with A 1 B 1 NH. General procedures for carrying out this reaction are given in J. Chem. Soc., 2195 (1951). In this class A 1 and B 1 are the same or different radicals selected from the group consisting of H, alkyl of from 1 to 7 carbon atoms, and aromatic of from 6 to 10 carbon atoms.
Representative compounds involved in this method are:
TABLE V__________________________________________________________________________R.sub.1 R.sub.2 Reagent Final Product__________________________________________________________________________H H ammonia 5'-O-(thiocarbamoyl)ara-cytidineCH.sub.3 H methyl amine 5'-O-(methyl thiocarbamoyl)ara- cytidineC.sub.2 H.sub.5 H ethyl amine 5'-O-(ethyl thiocarbamoyl)ara- cytidineCH.sub.3 CH.sub.3 dimethyl amine 5'-O-(dimethyl thiocarbamoyl)ara- cytidineC.sub.2 H.sub.5 C.sub.2 H.sub.5 diethyl amine 5'-O-(diethyl thiocarbamoyl)ara- cytidine ##STR81## CH.sub.3 N-methyl aniline 5'-O-(methylphenylthiocarbamoyl)- ara-cytidine__________________________________________________________________________
Where the acyl radical attached to the 5'-oxygen of ara-cytidine is ##STR82## the preparation is analogous to that of using the carboxylic acid chlorides, but using the appropriate sulfonyl chloride. In this class R 2 is a radical selected from the group consisting of alkyl of from 1 to 7 carbon atoms, aromatic of from 6 to 10 carbon atoms, and substituted aromatic of from 6 to 12 carbon atoms. Representative acylating agents and final products are:
TABLE VI__________________________________________________________________________ ##STR83##R.sub.2 Acylating Agent Final Product__________________________________________________________________________CH.sub.3 methanesulfonyl chloride 5'-O-methylsulfonyl-ara- cytidine ##STR84## benzenesulfonyl chloride 5'-O-phenylsulfonyl- ara-cytidine ##STR85## p-bromobenzenesulfonyl chloride 5'-O-(p-bromophenylsul- fonyl)ara-cytidine ##STR86## p-nitrobenzenesulfonyl chloride 5'-O-(p-nitrophenylsul- fonyl)ara-cytidine ##STR87## p-toluenesulfonyl chloride 5'-O-(p-tolylsulfonyl)- ara-cytidine ##STR88## 2,4,6-triisopropylbenzenesul- fonyl chloride 5'-(2,4,6-triisopropyl- phenylsulfonyl)ara - cytidine__________________________________________________________________________
Where the acyl radical attached to the 5'-oxygen of ara-cytidine is ##STR89## the preparation of the acylating agent is by the known method of reacting ROH with SOCl 2 to produce the acylating agent ##STR90## which is then used analogously to the carboxylic acid chlorides. In this class R 3 is a radical selected from the group consisting of aliphatic of from 1 to 20 carbon atoms, aromatic of from 6 to 10 carbon atoms, and araliphatic of from 7 to 12 carbon atoms. Representative compounds involved are:
TABLE VII______________________________________ ##STR91## ReagentR.sub.3 (+SOCl.sub.2) Final Product______________________________________H sulfur trioxide ara-cytidine 5'-sulfateCH.sub.3 methanol + thi- ara-cytidine onyl chloride 5'-methyl sul- fateC.sub.2 H.sub.5 ethanol + thi- ara-cytidine onyl chloride 5'-ethyl sul- fate ##STR92## phenol + thio- nyl chloride ara-cytidine 5'-phenyl sul- fate ##STR93## benzyl alcohol + thionyl chloride ara-cytidine 5'-benzyl sul- faten-CH.sub. 3 (CH.sub.2).sub.17 n-octadecyl al- ara-cytidine cohol + thionyl 5'-octadecyl chloride sulfate______________________________________
Where the acyl radical attached to the 5'-oxygen of ara-cytidine is ##STR94## the preparation of the acylating agent can be carried out by known methods. General procedures using an aliphatic alcohol in combination with dicyclohexylcarbodiimide and phosphorus oxychloride (POCl 3 ) are described in J. Am. Chem. Soc. 80, 6212 (1958). General procedures using di-substituted (R 4 and R 5 ) phosphochloridates as acylating agents are described in Angew. Chem. Internat. Edit. 6, 362 (1967). General procedures using substituted phosphates (R 4 ) and dicyclohexylcarbodiimide are described in Chem. Ber. 100, 2228 (1967). In this class R 4 and R 5 are the same or different radicals selected from the group consisting of alkyl of from 1 to 7 carbon atoms and haloalkyl of from 1 to 7 carbon atoms. Representative compounds involved are:
TABLE VIII__________________________________________________________________________ ##STR95##R.sub.4 R.sub.5 Reactants Final Products__________________________________________________________________________H CCl.sub.3 CH.sub.2 β, β, β-trichloroethylphos- β, β, β-trichloroethyl- phate + DCC (5'-ara-cytidylate)CH.sub.3 CH.sub.2 CH.sub.3 CH.sub.2 diethylphosphoro chloridate diethyl-(5'-ara-cytidyl- ate)CCl.sub.3 CH.sub.2 CCl.sub.3 CH.sub.2 bis-β,β,β-trichloroethyl- bis-β,β,β-trichloroethyl- phosphoro chloridate (5'-ara-cytidylate)__________________________________________________________________________
Where the acyl radical attached to the 5'-oxygen of ara-cytidine is ##STR96## the acylating agent is and the acylation is carried out following known procedures for the preparation of carbonate esters. In this class R 6 is a radical selected from the group consisting of aliphatic of from 1 to 20 carbon atoms, aromatic of from 6 to 10 carbon atoms, and araliphatic of from 7 to 12 carbon atoms. Representative compounds are:
TABLE IX______________________________________ ##STR97##R.sub.6 Reagent Product______________________________________CH.sub.3 methyl chloro- ara-cytidine 5'- formate methyl carbonateC.sub.2 H.sub.5 ethyl chloro- ara-cytidine 5'- formate ethyl carbonate ##STR98## carbobenzoxy chloride ara-cytidine 5'- phenyl carbonateCH.sub.3 (CH.sub.2).sub.7 octyl chloro- octanyl(5'-ara- formate cytidylyl)carbo- nateCH.sub.3 (CH.sub.2).sub.15 hexadecyl chloro- ara-cytidine 5'- formate hexadecyl carbo- nate ##STR99## phenyl chloro- formate ara-cytidine 5'- phenyl carbonate______________________________________
Where the acyl radical attached to the 5'-oxygen of ara-cytidine is ##STR100## the final product is prepared by reacting the intermediate compound, produced as described above in connection with Table VIII, N 4 -trichloroethoxycarbonyl-ara-cytidine-5'-phosphate, with the appropriate amine compound in the presence of dicyclohexylcarbodiimide. General analogous procedures are described in J. Am. Chem. Soc. 80, 3752 (1958). In this class A 2 and B 2 are the same or different radicals selected from the group consisting of H and alkyl of from 1 to 7 carbon atoms. Representative compounds involved are:
TABLE X__________________________________________________________________________ ##STR101##A.sub.2B.sub.2 Amine Final Product__________________________________________________________________________ (NTCEC)H H pCa + DCC + ara-cytidine 5'-phosphoramidate I II ammoniaCH.sub.3H I + II + methyl amine ara-cytidine 5'-(methyl phosphor- amidate)C.sub.2 H.sub.5H I + II + ethyl amine ara-cytidine 5'-(ethyl phosphor- amidate)CH.sub.3CH.sub.3 I + II + dimethyl amine ara-cytidine 5'-(dimethyl phos- phoramidate)C.sub.2 H.sub.5C.sub.2 H.sub.5 1 + II + diethyl amine ara-cytidine 5'-(diethyl phos- phoramidate)__________________________________________________________________________ I = N.sup.4 -trichloethoxycarbonyl-ara-cytidine 5'-phosphate II = DCC = dicyclohexylcarbodiimide
Where the acyl radical attached to the 5'-oxygen of ara-cytidine is ##STR102## the acylating agent is prepared in accordance with J. Am. Chem. Soc. 88, 4292 (1966), and with Angew. Chem. Internal. Edit. 6, 362 (1967), previously referred to in connection with Table VIII. In this class A 2 and B 2 have the meanings given above with respect to Table X. Representative compounds involved are:
TABLE XI__________________________________________________________________________ ##STR103##A.sub.2B.sub.2 Acylating Agent Final Product__________________________________________________________________________H C.sub.2 H.sub.5 ethyl dichlorothiophosphate ara-cytidine 5'-(o-ethyl- phosphorothioate)C.sub.2 H.sub.5C.sub.2 H.sub.5 diethyl dichlorothiophosphate ara-cytidine 5'-(o,o-di- ethyl phosphorothioate)H H triimidazolyl 1-phosphinsul- ara-cytidine 5'-phosphoro- fide thioate__________________________________________________________________________
We have discovered a further method for the preparation of the 5'-esters described in this invention without resort to a special blocking group for the amino function. The alternate route takes advantage of the fact that when the amino group is protonated it is unreactive toward acylating agents. Thus, we simply use the proton as the blocking group, reacting a suitably activated acid, such as an acid chloride or anhydride, with an acid salt, such as the hydrochloride salt, of the nucleoside.
As an example, one equivalent of palmityl chloride is allowed to react at room temperature with a solution of ara-cytidine hydrochloride in dimethylacetamide or dimethylformamide. After a few hours, thin layer chromatgraphy shows that the main product is 5'-O-palmityl ara-cytidine, with small amounts of diesterified products. The solvent is evaporated in vacuo, and the oil is converted to a solid by trituration with aqueous bicarbonate. The solid is collected on a filter and washed with water, pressed dry, and washed thoroughly with ethyl acetate to remove impurities. The resultant product, obtained in better than 50% yield, shows a single, ultraviolet-absorbing spot on thin layer chromatography and is essentially analytically pure.
The method is applicable to all nucleosides bearing an amino group, such as nucleosides of adenine and guanine. The acyl moiety includes that of any acid that can be suitably activated, for example by the formation of an acid chloride, anhydride, or mixed anhydride, such that it can form an ester bond with an alkyl hydroxyl group but is unreactive towards a protonated amino group. The 5'-O-acryl derivatives of ara-cytidine described in the preceding discussions as made by the N 4 -trihaloethoxycarbonyl-protected method, and illustrated in the above Tables I to XI, can also be made by the proton-protected route. The acylating agents used in the N 4 -trihaloethoxycarbonyl-protected method and exemplified in Tables I to XI are applicable in the proton-protected route.
The proton-protected process is illustrated in Examples 24 to 32.
EXAMPLE 1 Preparation of N 4 -trichloroethoxycarbonyl-5-O-trityl ara-cytidine ##STR104##
A 193.69 g. (0.40M) sample of 5'-O-trityl ara-cytidine is dissolved in 4 l. of freshly distilled anhydrous pyridine. The solution is cooled to 3° and treated with 84.4 g. (0.40M) of trichloroethoxycarbonyl chloride. The solution is stirred at 3° for 4 hours and then allowed to come to 25° over ca. 18 hours. The pyridine is distilled at 40° in vacuo and the gummy residue treated with 1 l. of methylene chloride. A solid (23.7 g.) separated and is removed by filtration. Thin layer chromatography (TLC) shows the material to be starting material. The methylene chloride solution is washed 3 times with 0.1 N hydrochloric acid and once with saturated salt solution. After drying over sodium sulfate the methylene chloride is allowed to slowly evaporate, whereupon crystals are deposited. The crystals are collected by filtration, washed with cold methylene chloride and dried giving 64.5 g. of desired product. TLC of the methylene chloride mother liquors show spots moving faster than the product which are probably materials acylated at 2' and 3' position. These are hydrolyzed by treating the mother liquor residue with 1 l. of tetrahydrofuran and 1 l. of 0.3 N sodium hydroxide. After 1.5 hours all the faster moving TLC spots have disappeared. The reaction is acidified to pH 6.5 with concentrated hydrochloric acid. The tetrahydrofuran is distilled in vacuo and the aqueous residue extracted with methylene chloride. The methylene chloride is washed and dried as above and again set out to evaporate. Again crystals are deposited. These are collected and washed giving 42.5 g. of product. The mother liquors are evaporated further and deposit another 45.5 g. of material which this time is about 50--50 product and starting material as seen by TLC. The 45.5 g. is heated with 500 ml. of acetone and the residual material removed by filtration. This is found to be trityl ara-cytidine. The acetone mother liquors are evaporated to dryness and crystallized from methylene chloride by slow evaporation giving 19 g. of product. The total yield is thus 126 g. of product or 48% of theory. A sample is prepared for analyses by crystallizing it twice from methylene chloride.
Anal. Calcd. for C 31 H 28 Cl 3 N 3 O 7 : C, 56.30; H, 4.27; Cl, 16.11; N, 6.36. Found: C, 56.46; H, 4.30; Cl, 15.25; N, 7.26.
Ultraviolet Spectrum λ max EtOH mμ (ε × 10 -3 )!: 232 (11.8), 296 (5.38).
Infrared Spectrum (ν mull): 3380, 3200, 3120 sh, 1765, 1650, 1620, 1570, 1505, 1330, 1245, 1200, 1100 m, 1085, 1065, 810, 785, 770, 750, 740, 715 and 705.
EXAMPLE 2 Preparation of N 4 -trichloroethoxycarbonyl ara-cytidine ##STR105##
A 116.2 g. (0.175 M) quantity of N 4 -trichloroethoxycarbonyl-5'-O-trityl ara-cytidine is treated with 1 l. of 80% (V/V) acetic acid for 48 hours at 25°. The mixture deposits crystalline trityl containing material during this period which is removed by filtration. The filtrate is evaporated to dryness in vacuo and the last traces of acid removed by codistillation in vacuo with several portions of ethanol. The glassy residue is crystallized from ethanol giving 62.5 g. of product. These materials are found by NMR analysis to contain between 10 and 15% of triphenylmethylcarbinol and/or its ethyl ether. The compound is purified for analysis by chromatography on silica gel, eluting with cyclohexane-ethyl acetate-ethanol (5:3:1) and subsequent crystallization from methylene chloride.
Anal. Calcd. for C 12 H 14 Cl 3 N 3 O 7 : C, 34.43; H, 3.37; Cl, 25.41; N, 10.04. Found: C, 34.59; H, 3.61; Cl, 24.82; N, 9.99.
Infrared Spectrum (ν cm .spsb.-1 mull ): 3400, 1765, 1640, 1575, 1510, 1330, 1275, 1235, 1195, 1120, 1105, 1070, 1055, 1035, 810, 745.
Ultraviolet Spectrum λ max EtOH (ε × 10 -3 )!: 212 (21.8), 239 (14.5), 296 (8.3).
EXAMPLE 3 Preparation of 5'-O-pivaloyl-N 4 -trichloroethoxycarbonyl ara-cytidine ##STR106##
A 4.18 g. (10 millimole) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of freshly distilled anhydrous pyridine. The solution is treated dropwise with 1.32 g. (1.4 ml., 11 millimoles) of pivaloyl chloride in 10 ml. of pyridine at 25°. TLC silica gel; cyclohexane-ethyl acetate-ethanol (5:3:1)! indicates the reaction has not progressed significantly after 48 hours. Thus, another 1.32 g. (11 millimoles) of pivaloyl chloride in 10 ml. pyridine is added and then reaction allowed to stand yet 24 hours longer. TLC indicates that little if any of the starting material remains. The reaction mixture is pured into 60 ml. of water and the mixture evaporated to dryness in vacuo. The last traces of pyridine are removed by codistillation several times with toluene in vacuo. The residue is dissolved in chloroform and washed with water, saturated sodium chloride and dried over sodium sulfate. The chloroform is distilled in vacuo and the residue crystallized from acetone giving 1.75 g. of product.
In place of pivaloyl chloride, pivaloyl anhydride can be used as the pivaloylating agent in the above sample.
In place of pivaloyl chloride there can be substituted isobutyryl chloride or β-chloropivaloyl chloride, thus producing, respectively, 5'-O-isobutyryl-N 4 -trichloroethoxycarbonyl ara-cytidine and 5'-O-β-chloropivaloyl-N 4 -trichloroethoxycarbonyl ara-cytidine.
EXAMPLE 4 Preparation of 5'-O-pivaloyl ara-cytidine ##STR107##
A 1.50 g. (3.0 millimole) sample of 5'-O-pivaloyl-N 4 -trichloroethoxycarbonyl ara-cytidine is treated with 25 ml. of 90% (V/V) acetic acid and 2.0 g. (31 millimoles) of zinc dust and the mixture stirred ca. 18 hours at 25°. The reaction mixture is then filtered and the filtrate evaporated to dryness in vacuo. The residue is chromatographed on 200 g. of silica gel packed and eluted with cyclohexane-ethyl acetate-ethanol (5:3:1). The first forty 100 ml. fractions contain none of the desired product, so a switch is made to the solvent system, methyl ethyl ketone-acetone-water (72:20:8). Fractions 1-18 are combined and evaporated to dryness. Crystallization of the residue from methanol gives 715 mg. of product, m.p. 255° (dec.). Like results are obtained substituting for the starting material, 5'-O-isobutyryl-N 4 -trichloroethoxycarbonyl ara-cytidine and 5'-O-β-chloropivaloyl-N 4 -trichloroethoxycarbonyl ara-cytidine producing, respectively, 5'-O-isobutyryl ara-cytidine and 5'-O-β-chloropivaloyl ara-cytidine.
In place of pivaloyl chloride in Example 3, benzoyl chloride can be substituted to provide 5'-O-benzoyl-N 4 -trichloroethoxycarbonyl ara-cytidine which can be substituted in the process of Example 4 above to provide 5'-O-benzoyl ara-cytidine.
EXAMPLE 5 Preparation of 5'-O-benzoyl cytosine arabinoside hydrochloride
5'-O-benzoyl cytosine arabinoside (65 g.) is dissolved in 250 ml. methanol with the aid of 19 ml. concentrated hydrochloric acid. Ether (500 ml.) is added to opalescence. The hydrochloride rapidly crystallizes. It is collected, washed with methanol-ether (1:2), ether, and dried, weight 60.5 g., m.p. 204°-205° dec. Ether is added to the mother liquor to opalescence. The second crop is collected, washed with ether, and dried, weight 6.5 g. (total yield 67 g., 98.5%), m.p. 200°-201° dec.
EXAMPLE 6 Preparation of 5'-O-palmityl ara-cytidine ##STR108##
A 4.18 g. (10 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of anhydrous redistilled pyridine and treated dropwise at room temperature with 3.0 g. (11 millimoles) of palmityl chloride dissolved in 10 ml. of methylene chloride. After standing 18 hours 25°, the reaction mixture is poured into 60 ml. of water and the solvent distilled in vacuo until about 10 ml. remains. A semisolid separates and is obtained by decantation followed by washing with water. The resultant mass is crystallized from methanol giving 5.5 g. of material that is presumed to be 5'-O-palmityl-N 4 -trichloroethoxycarbonyl ara-cytidine on the basis of its conversion to the desired product. This material is dissolved in 100 ml. of 90% acetic acid and treated with 10 g. of zinc dust. The reaction is stirred for 6 hours at 25°. The zinc remaining is removed by filtration and the filtrate evaporated to dryness in vacuo. The last traces of acetic acid are removed by repeated codistillation in vacuo with ethanol. The residue is then chromatographed on 100 g. of silica gel, packed and eluted with cyclohexane-ethyl acetate-ethanol (5:3:1). After taking ten 100 ml. fractions, the solvent is switched to methyl ethyl ketone-acetone-water (72:20:8) and another ten 100 ml. fractions taken. Fractions 14-20 are combined and evaporated to dryness. The residue is crystallized from methanol giving 870 mg. of product, m.p. 139°-141°. A sample is submitted for analysis after two further crystallizations from methanol, m.p. 143°-146° .
Anal. Calcd. for C 25 H 43 N 3 O 6 : C, 62.34; H, 9.00; N, 8.72 Found: C, 62.86; H, 9.19; N, 8.47, 8.72.
Ultraviolet Spectrum λ max EtOH mμ (ε × 10 -3 )!: 273 (8.30).
Infrared Spectrum (ν cm .spsb.-1 mull ): 3430, 3330, 3280 sh, 1740, 1665 sh, 1635, 1600, 1535, 1495, 1485, 1290, 1255, 1195, 1175, 1110, 1095, 1040, 860, 790, 785, 780.
NMR Spectrum: Supports proposed structure.
EXAMPLE 7 Preparation of 5'-O-palmityl cytosine arabinoside hydrochloride
5'-palmityl cytosine arabinoside, 55g. (0.114 mole) is dissolved in a mixture of MEK*, ml. methanol and 10.5 ml. concentrated hydrochloric acid. The solution is diluted with ether until crystallization ensues, and then further diluted to 4 liters with ether. The crystalline hydrochloride is collected, washed with ether, and dried. Yield 53.8 g. (91%), m.p. 180°-182°.*
A 4.18 g. (10 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of anhydrous redistilled pyridine and resultant solution treated dropwise with a solution of 1.8 g. (11 millimoles) of octanoyl chloride in 10 ml. of methylene chloride. The reaction mixture is stirred for 18 hours at room temperature and then poured into 60 ml. of water. The solvent is reduced in volume to about 10 ml. by distillation in vacuo. The mother liquors are decanted from the solid which separates. The solid is washed with water, filtered, dried and crystallized from methanol giving 3.5 g. of 5'-O-octanoyl-N 4 -trichloroethoxycarbonyl ara-cytidine. This material is dissolved in 50 ml. of 90% acetic acid and the solution is treated with 5 g. of zinc dust. After the reaction mixture has shaken 5 hours at 25°, the residue zinc solids are removed by filtration and the filtrate evaporated to dryness in vacuo. The last traces of acetic acid are removed by redistillation in vacuo with several portions of ethanol. The residue is chromatographed on 100 g. of silica gel, packed and eluted with methyl ethyl ketone-acetone-water (72:20:8). Fractions of 100 ml. volume are collected. Fractions 4-8 are combined and evaporated to dryness. The residue is crystallized from methanol giving 1.2 g. of product, m.p. 161.5°-162.5°. A sample is submitted for analyses after another crystallization from aqueous methanol, m.p. 124°-125°. The melting point change apparently reflects a change in the state of hydration or change in crystal structure since TLC indicates the material to be unchanged.
Anal. Calcd. for C 17 H 27 N 3 O 6 . H 2 O: C, 52.69; H, 7.55; N, 10.85. Found: C, 52.81; H, 7.97; N, 11.32.
Ultraviolet Spectrum λ max EtOH mμ (ε × 10 -3 )!: 274 (8.15).
Infrared Spectrum (ν cm .spsb.-1 mull ): 3530, 3480, 3450, 3390, 3320, 3280, 3210, 1725, 1710, 1655, 1630, 1530, 1490, 1280, 1240, 1195, 1175, 1130, 1115, 1100, 1090, 1050, 1040, 810, 780.
NMR Spectrum: Supports proposed structure.
The procedures of Examples 5-6 can be followed, substituting stearyl chloride and oleyl chloride for the acylating agents of the examples, producing, respectively, 5'-O-stearyl ara-cytidine and 5'-O-oleyl ara-cytidine.
EXAMPLE 9 Preparation of 5'-O-acetyl ara-cytidine ##STR110##
A 4.18 g. (10 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of anhydrous freshly distilled pyridine. The resultant solution is treated dropwise with 1.03 g. (10 millimoles) of acetic anhydride. The reaction mixture is stirred at 25° for 18 hours, then poured into 60 ml. of water ane evaporated to dryness. The residue is chromatographed on 100 g. of silica gel and eluted with cyclohexane-ethyl acetate-ethanol (5:3:1). The fractions containing the material with an Rf only slightly faster than the starting material are combined and evaporated to dryness. Crystallization of the residue gives 1.05 g. of material presumed to be 5-O-acetyl-N 4 -trichloroethoxycarbonyl ara-cytidine on the basis of its subsequent conversion to 5'-O-acetyl ara-cytidine. This material is dissolved in 50 ml. of 90% (V/V) acetic acid and the solution treated with 1.0 g. of zinc dust. The reaction mixture is shaken for 6 hours at 25°. The zinc solids remaining are then removed by filtration and the filtrate evaporated to dryness in vacuo. The residual gum is freed from traces of acetic acid by codistillation in vacuo with several portions of ethanol. The residue is chromatographed on 100 g. of silica gel, packed and eluted with cyclohexane-ethyl acetate-ethanol (5:3:1). The solvent is switched to methyl ethyl ketone-acetone-water (72:20:8). The fractions containing the desired product are combined and evaporated to dryness. The material is thus rechromatographed on 50 g. of silica gel as described above. The fraction from this column containing the desired material are combined and evaporated to dryness. The residue is crystallized from aqueous methanol-benzene giving 300 mg. of product, m.p. 115-117.5.
Anal. Calcd. for C 11 H 15 N 3 O 6 .1/2H 2 O: C, 44,90; H, 5.48; N, 14.28. Found: C, 45.13; H, 5.95; N, 14.55.
Ultraviolet Spectrum λ max EtOH mμ (ε × 10 -3 ) !: 273 (8.65).
Infrared Spectrum (ν cm .spsb.-1 mull ): 3400, 3340, 3210, 1745, 1660, sh 1640, 1610, 1535, 1490, 1280, 1255, sh, 1245, 1230, 1105, 1080, 1070, 1050, 810, 780, 690.
MNR Spectrum: Supports proposed structure.
EXAMPLE 10 Preparation of 5'-O-(2,4,6-trimethylbenzoyl) ara-cytidine. ##STR111##
A 4.18 g. (10 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of anhydrous redistilled pyridine and the resultant solution treated dropwise with 2.0 g. (11 millimoles) of 2,4,6-trimethylbenzoyl chloride dissolved in 10 ml. of methylene chloride. After 3 days at 25°, TLC indicates that starting material is still present. Thus, another 2.0 g of 2,4,6-trimethylbenzoyl chloride is added and the reaction allowed to stand another 24 hours at 25°. The reaction mixture is then poured into water and evaporated to dryness in vacuo. The residue is chromatographed on 100 g. of silica gel. The product is eluted with methanol-benzene (5:95). The fractions containing the material with Rf only slightly faster than the starting material are combined and evaporated to dryness. The residue is crystallized from methanol giving 2.0 g. of material presumed to be N 4 -trichloroethoxycarbonyl-5'-O-(2,4,6-trimethylbenzoyl) ara-cytidine on the basis of its conversion to 5'-trimethylbenzoyl ara-cytidine, m.p. 122°-125° (dec.). This material is dissolved in 50 ml. of zinc dust and shaken for 6 hours. The zinc containing solids are filtered from the reacting mixture and the filtrate evaporated to dryness in vacuo. The residue is chromatographed on 100 g. of silica gel, eluting with mixtures of methanol benzene (5:95) to pure methanol. The desired material is found in the methanol fractions, which are then combined and evaporated to dryness. The residue is crystallized from methanol giving 670 mg. of 5'-O-(2,4,6-trimethylbenzoyl) ara-cytidine, m.p. 252°-253° (dec.). A sample crystallized once more from methanol is submitted for analysis, m.p. 255°-256° (dec.).
Anal. Calcd. for C 19 H 13 N 3 O 6 .1/2 H 2 O; C, 57.28; H, 6.07; N, 10.55. Found: C, 57,15; H, 6.34; N, 10.86.
Ultraviolet Spectrum λ max EtOH mμ (ε × 10 -3 )!: 273 (9.40).
Infrared Spectrum (ν cm .spsb.-1 mull ): 3430 sh, 3400, 3340, 3280, 3210, 3120, 1720, 1695, 1655, 1635, 1625, 1535, 1490, 1285, 1175, 1120, 1115, 1095, 1070, 1055, 810, and 780.
MNR Spectrum: Supports proposed structure.
The use of acylating agent of p-nitrobenzoyl) chloride, o-toluoyl chloride, benzoyl chloride, 2,6-dimethylbenzoyl) chloride, 2,4,6-trimethylbenzoyl chloride, 1-fluorene carbonyl chloride, p-anisoyl chloride, 3,4,5-trimethoxybenzoyl chloride, p-toluoyl chloride, cyclohexane carbonyl chloride, picolinyl chloride of 2-thiophene carbonyl chloride produces, respectively, 5'-O-p-nitrobenzoyl ara-cytidine, 5'-O-toluoyl ara-cytidine, 5'-O-benzoyl ara-cytidine, 5'-O-2,6-dimethylbenzoyl ara-cytidine, 5'-O-2,4,6-trimethylbenzoyl ara-cytidine, 5'-O-fluorene carbonyl ara-cytidine, 5'-O-p-anisoyl ara-cytidine, 5'-O-3,4,5-trimethoxybenzoyl ara-cytidine, 5'-O-p-toluoyl ara-cytidine, 5'-cyclohexane carbonyl ara-cytidine, 5'-O-picolinyl ara-cytidine, and 5'-O-2-thiophene carbonyl ara-cytidine.
EXAMPLE 11 Preparation of 5'-O-adamantoyl ara-cytidine
5'-O-Trityl ara-cytidine (2.42 g., 5.0 millimoles) is dissolved in 50 ml. of redistilled pyridine and cooled in a dry ice-acetone bath until a slurry formed. The slurry is treated with β,β,β-trichloroethoxycarbonyl (TCEC) chloride (3.2 g., 15 millimoles). The mixture is agitated thoroughly and then allowed to stand at 0° for 20 hours. The reaction is warmed to 25° and maintained at that temperature for 4 hours. The pyridine is distilled at a temperature below 40° on a rotary evaporator. The residual gum is dissolved in 100 ml. of methylene chloride and washed 4 times with 0.1 N hydrochloric acid. The methylene chloride layer is dried (Na 2 SO 4 ) and distilled. The residual gum is treated with 200 ml. of 1% trifluoroacetic acid in chloroform for 2 hours at 25° to remove the trityl group. The chloroform solution is evaporated to dryness and the gum dissolved in pyridine and treated with adamantane-1-carboxylic acid chloride (1-adamantane carbonyl chloride) (1.0 g., 5 mM). The solution is warmed to 50° and maintained at that temperature for 24 hours. The pyridine is distilled on a rotary evaporator and the residue dissolved in 100 ml. of chloroform. The chloroform solution is washed with 200 ml. of water, 200 ml. of 4% sodium bicarbonate and twice with 200 ml. of water. The chloroform solution is dried (Na 2 SO 4 ) and distilled on a rotary evaporator. The residue is dissolved in 25 ml. of 90% acetic acid to which is added 2 g. of zinc dust. After standing 2 hours at room temperature the mixture is filtered and the filtrate distilled. The residue is dissolved in a minimum amount of chloroform and absorbed onto a 300 g. column of silica gel. The desired product is eluted with chloroform-methanol-acetic acid (80:20:1). The material is crystallized from methanol, giving 250 mg. of product.
EXAMPLE 12 Preparation of 5'-O-adamantoyl cytosine arabinoside hydrochloride
5'-O-adamantoyl cytosine arabinoside (42 g.) is suspended in 400 ml. methanol, and 12.5 ml. of concentrated hydrochloric acid is added to dissolve the material. Crystallization rapidly ensues and the mixture is diluted to one liter with ether. The crystalline product is collected, washed with ether and dried, weight 32.9 g., m.p, 246° dec. The mother liquor is concentrated and a second crop obtained, weight 3.5 g., m.p. 241° dec. (total yield = 36.4 g., 79%).
Substituting, as acylating agent, 1-norbornane carbonly chloride, 2-adamantane carbonyl chloride, 1-adamantaneacetyl chloride, α-chloro-3,5,7-trimethyl-1-adamantane acetyl chloride and 2-quinuclidine carbonyl chloride produces, respectively, 1-norbornane carbonyl ara-cytidine, 5'-O-2-adamantane carbonyl ara-cytidine, 5'-O-1-adamantane acetyl ara-cytidine, cytidine, 5'-O-α-chloro-3,5,7-trimethyl-1-adamantane ara-cytidine, and 5'-O-2-quinuclidine carbonyl ara-cytidine.
EXAMPLE 13 Preparation of 5'-O-(p-toluenesulfonyl) ara-cytidine ##STR112##
A 4.18 g. (10 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of freshly distilled anhydrous pyridine. The solution is treated dropwise with 2.85 g. of p-toluenesulfonyl chloride (15 millimoles) dissolved in 10 ml. of pyridine. The reaction mixture is allowed to stir at room temperature over the weekend, and then is poured into 60 ml. of water and taken to dryness at 50° on a rotary evaporator. The crude gum is then dissolved in 50 ml. of methanol and 5 g. of zinc dust added. The reaction mixture is then heated to boiling for 15 minutes. TLC is checked and shows no starting material left. The zinc is filtered and the preparation taken to dryness. The residue is then absorbed onto a 200 g. column of silica gel made up with cyclohexane, ethyl acetate, 95% EtOH (5:3:1). The column is eluted with 1 l. of this same solvent. This elutes only faster moving material which is discarded. The column is then eluted with 15, 100 ml. fractions of MEK*, acetone, H 2 O (72:20:8). Fractions 5-10 contain what appears to be the desired product. These fractions move a little slower than the starting material of TLC, and are combined and crystallized from methanol. Yield 950 mg., m.p. 158°-168° (dec. at 195° ). A sample is recrystallized from methanol for analysis, m.p. 171°-174°.
Anal. Calcd. for C 16 H 19 O 7 N 3 S: C, 48.36; H, 4.82; N, 10.57; S, 8.04. Found: C, 48.46; H, 5.25; N, 10.49; S, 8.13.
Ultraviolet Spectrum λ max EtOH (ε × 10 -3 )!: 224 (19.7); 269 sh (8.06); 273 (8.95).
Infrared Spectrum ν cm .spsb.-1 mull !: 3480, 3330 sh, 3280 sh. 3240 sh, 3210 sh, 1650, 1615, 1560 w, 1535, 1500, 1360, 1355, 1290, 1195, 1175, 1070, 1040, 980, 835, 820, 800, 785, 655.
Infrared spectrum is proper for the sulfonate.
EXAMPLE 14 Preparation of 5'-O-cyclobutyl carbonyl ara-cytidine ##STR113##
A 8.36 g. (20 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of freshly distilled anhydrous pyridine. The solution is treated dropwise at room temperature with stirring with 4.0 g. (about 22 millimoles) of cyclobutanecarboxylic acid anhydride in 10 ml. of CH 2 Cl 2 . The reaction mixture is allowed to stir at room temperature overnight and a TLC plate is run on the crude reaction in the morning. TLC still shows some starting material left, so the preparation is heated to 50° in a water bath for 3 hours. TLC is unchanged so the reaction mixture is poured into 30 ml. of water and taken to dryness at 50° on the rotary evaporator. The residue is then dissolved in CH 2 CL 2 and washed once with saturated bicarbonate, twice with water. At this point, there is a lot of precipitate in the CH 2 Cl 2 layer. This is filtered and washed with a small amount of CH 2 Cl 2 . Yield 3.4 g. This material has one major spot with a trace of the slower moving starting material. The CH 2 Cl 2 solution (the mother liquors) contain 3 faster moving spots plus a trace of the crystalline solid plus the starting material. The 3.4 g. of crystalline solid is dissolved in 100 ml. of methanol and heated to boiling with 3.5 g of zinc dust for 10 minutes on the steam bath. TLC shows no starting material left at this point. The zinc is filtered off and the methanol solution taken to dryness at 50° on the rotary evaporator. The clear residue is then absorbed onto a 200 g. column of silica gel made up with MEK, acetone and H 2 O (72:20:8) and the column eluted with 15, 50 ml. fractions of the same solvent. Based on TLC results, fractions 9-13 are combined with recrystallized from acetone. Yield 1.045 g. Recrystallized from acetone for analysis, a sample has a m.p. 200.0°-200.5°. TLC is the same as the first crop material.
Anal. Calcd. for C 14 H 17 O 6 N 3 : C, 51.68; H, 5.89; N, 12.92. Found: C, 51.29; H, 6.13; N, 13.25.
Ultraviolet Spectrum λ max EtOH (ε × 15 -3 )!: 230 sh (7.90); 273 (9.00).
Infrared Spectrum ν cm .spsb.-1 mull !: 3440, 3330, 3260, 3210, 1700, 1655, 1635, 1600, 1525, 1295, 1255, 1185, 1135, 1105, 1050, 810.
Ultraviolet spectrum, infrared spectrum and NMR are proper for the proposed structure.
EXAMPLE 15 Preparation of 5'-O-(p-anisoyl) ara-cytidine ##STR114##
A 8.36 g (20 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of freshly distilled anhydrous pyridine. The solution is treated dropwise with stirring at room temperature with 3.75 g. (22 millimoles) of anisoyl chloride in 10 ml. of CH 2 Cl 2 . The reaction mixture is allowed to stir at room temperature overnight and a TLC plate is run on the crude mixture in the morning. TLC still shows some starting material left. The preparation is heated to 50° in a water bath for 3 hours. TLC is unchanged so the reaction mixture is poured into 30 ml. of water and taken to dryness at 50° on a rotary evaporator. The residue is dissolved in CH 2 Cl 2 and washed once with 100 ml. of saturated bicarbonate, once with H 2 O and dried over sodium sulfate. The CH 2 Cl 2 solution is then absorbed onto a 200 g. column of silica gel and eluted with 20, 50 ml. fractions of cyclohexane, ethyl acetate, 95% EtOH (5:3:1). Based on TLC results, fractions 10-18 are combined in methanol (100 ml.) and treated with 4 g. of zinc dust for 15 minutes at reflux on the steam bath. TLC at this point shows no starting material left so the solution is filtered free of zinc and the preparation taken to dryness on the rotary evaporator. The residue is then absorbed onto a 200 g. column of silica gel made up with MEK, acetone, H 2 O and eluted with 20, 50 ml. fractions of the same solvent. Based on TLC results, fractions 10-16 are combined and recrystallized from methanol. Yield 795 mg., m.p. 225°-227° (dec.). Recrystallized from methanol a sample for analysis has m.p. 225°-227° (dec.).
Anal. Calcd. for C 17 H 19 O 7 N 3 : C, 54.11; H, 5.08; N, 11.14. Found: C, 53.95; H, 4.81; N, 11.09.
Ultraviolet Spectrum λ max EtOH (ε × 10 -3 )!: 258 (14.50); 271 sl sh (19.20); 278 sl sh (13.00); 283 sl sh (4.90).
The shift in the main absorption is due to the ##STR115## as the 278 and 283 sl sh's. Ultraviolet spectrum supports the proposed structure.
Infrared Spectrum ν cm .spsb.-1 mull !: 3420, 3310, 1720, 1665, 1630, 1600, 1530, 1510, 1490, 1275, 1250, 1170, 1100, 1035, 850, 825, 790, and 770.
NMR and infrared spectrum are proper for the proposed structure.
EXAMPLE 16 Preparation of 5'-O-cyclohexyl carbonyl ara-cytidine ##STR116##
A 8.36 g. (20 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of freshly distilled anhydrous pyridine. The solution is treated dropwise with stirring and at room temperature with 3.22 g. (about 22 millimoles) of cyclohexanecarboxylic chloride in 10 ml. of CH 2 Cl 2 . The chloride is made by refluxing cyclohexanecarboxylic acid in thionyl chloride, removing the thionyl chloride on the rotary evaporator and distilling the chloride, boiling point 180°-181°. The reaction mixture is allowed to stir at room temperature overnight. A TLC is run on the crude mixture in the morning. The TLC still shows some starting material left so the preparation is heated to 50° in a water bath for 3 hours. The reaction mixture is poured into 30 ml. of water and taken to dryness at 50° on the rotary evaporator. The residue is then absorbed onto a 200 g. column of silica gel. and eluted with 25, 50 ml. fractions of cyclohexane, ethylacetate, 95% EtOH (5:3:1). The column is made up with the same solvent. TLC's are run on fractions 5-14 and on fraction 23. Based on TLC results, fractions 6-11 are combined. 3.387 g. in 100 ml. of methanol is treated with 4 g. of zinc dust at reflux for 15 minutes. TLC shows no starting material left at this point. The zinc is filtered off and the filtrate taken to dryness at 50° on the rotary evaporator. The residue is then absorbed onto a 200 g. column of silica gel made up with MEK, acetone, H 2 O (72:20:8) and eluted with 20, 50 ml. fractions of the same solvent. Based on TLC results, fractions 10-14 are combined and recrystallized from methanol-acetone. Yield 1.384 g., m.p. sinters at 206° dec. at 229° (one spot by TLC). Recrystallized 100 mg. from the same solvent, a sample for analysis sinters about 210° and dec. at 231°.
Anal. Calcd. for C 16 H 23 O 6 N 3 .1/2H 2 O: C, 53.03; H, 6.68; N, 11.60. Found: C, 52.85; H, 6.66; N, 11.95.
Ultraviolet Sprectrum λ max EtOH (ε × 10 -3 )!: 315 sl sh (10.20); 230 sh (7.65); 273 (8.75).
Infrared Spectrum ν cm .spsb.-1 mull !: 3420, 3340, 3210, 1735, 1715, 1655, 1640, 1625, 1530, 1490, 1285, 1245, 1200, 1180, 1110, 1095, 1055, 815, and 780.
Ultraviolet spectrum supports the proposed structure.
NMR and infrared spectrum are proper for the proposed structure.
EXAMPLE 17 Preparation of 5'-O-β-chloropivaloyl ara-cytidine ##STR117##
A 8.36 g. (20 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of freshly distilled anhydrous pyridine. The solution is treated dropwise with stirring at room temperature with 3.4 g. (about 22 millimoles) of β-chloropivalic acid chloride. The chloride is made by refluxing β-chloropivalic acid (Aldrich) in an excess of thionyl chloride, distilling off the thionyl chloride, then the acid chloride, b.p. 158°-160°. After 18 hours at room temperature there is still, starting material left by TLC. Another 3.4 g. of the acid chloride is added in 10 m. of Ch 2 Cl 2 . After 4 hours at room temperature the TLC is still mostly unchanged. The reaction mixture is warmed on the steam bath for 5-10 minutes. TLC at this point shows only a trace of the starting material. The preparation is poured into 60 ml. of water and taken to dryness on the rotary evaporator at 50°. The residue is then absorbed into a 200 g. column of silica gel made up with cyclohexane, ethyl acetate, 95% EtOH (5:3:1) and eluted with 20, 50 ml. fractions of the same solvent. Fractions 6-20 are slurried in a small amount of methanol and filtered and washed with 10-15 ml. of cold methanol. This material has one major spot by TLC with a trace of faster moving material and a trace of the starting material. Yield is 6.85 g. This material is dissolved in 100 ml. of methanol and heated to reflux with 7 g. of zinc dust for 15 minutes. TLC shows no starting material left so the zinc was filtered off, washed with methanol and the filtrate taken to dryness at 50° on the rotary evaporator. The residue is absorbed onto a 200 g. column of silica gel and eluted with 25, 50 ml. fractions of MEK, acetone, H 2 O (72:20:8). TLC's are run on crystalline fractions 11, 15 and 21. Based on TLC results, fractions 11-21 are combined are recrystallized from methanol. The compound will crystallize from H 2 O also. Yield 2.50 g., m.p. 238°-40° dec. A sample recrystallized for analysis from the same solvent has m.p. 238°-40° dec. One spot by TLC.
Anal. Calcd. for C 14 H 20 O 6 N 3 Cl: C, 46.8; H, 5.57; N, 11.61; Cl, 9.80. Found: C, 46,42; H, 5.68; N, 11.46; Cl, 10.16.
Ultraviolet Spectrum λ max EtOH (ε × 10 -3 )!: 216 sl sh (10.20); 229 sh (7.90); 273 (9.05).
Infrared Spectrum ν cm .spsb.-1 mull !: 3410, 3440, 3340, 3260, 3220, 1710, 1655, 1635, 1600, 1565, 1525, 1484, 1300, 1255, 1190, 1125, 1100, 1055, and 810.
EXAMPLE 18 Preparation of ara-cytidine 5'-methyl carbonate ##STR118##
A 4.18 g. (10 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 25 ml. of freshly distilled anhydrous pyridine. The solution is treated dropwise at room temperature with 1.0 g. of methyl chloroformate (about 22 millimoles) dissolved in 10 ml. of CH 2 Cl 2 . The solution is allowed to stir at room temperature overnight and the TLC is checked in the morning. TLC showed some starting material left. The preparation is taken to dryness at 50° on the rotary evaporator and the residue absorbed onto a 150 g. column of silica gel made up with cyclohexane, ethyl acetate, 95% EtOH (5:3:1). The column is eluted with 20, 50 ml. fractions of the same solvent. TLC's of fractions 9-17 shows fractions 10-13 to contain the desired ##STR119## derivative of N 4 -trichloroethoxycarbonyl ara-cytidine. These fractions of 2.465 g. are combined in 50 ml. of methanol and treated at reflux for 15 minutes on the steam bath with 3 g. of zinc dust. TLC shows no starting material left. The zinc is then filtered and the preparation taken to dryness on the rotary evaporator. The residue is then absorbed onto a 150 g. column of silica gel made up with MEK, acetone, methanol (5:2:3) and eluted with 25, 50 ml. fractions of the same solvent. TLC's are run on fractions 17-22 and based on the TLC results, fractions 19-22 are combined and recrystallized from methanol. Yield is 390 mg., m.p. 188.5°-90° dec. (foamed up the tube).
Anal. Calcd. for C 11 H 15 O 7 N 3 : C, 43.85; H, 5.02; N, 13.95. Found: C, 44.16; H, 5.26; N, 13.64.
Ultraviolet Spectrum λ max EtOH (ε × 10 -3 )!: 215 sl sh (10.35); 230 (8.00); 273 (9.15).
Infrared Spectrum ν cm .spsb.-1 mull !: 3460, 3340, 3250, 3230, 3180, 1765, 1640, 1625, 1560, 1530, 1500, 1315, 1280, 1090, 1070, 1035, 990 and 780.
Ultraviolet spectrum, infrared spectrum and NMR are all proper for the proposed structure.
EXAMPLE 19 Preparation of 5'-O-(p-nitrobenzoyl) ara-cytidine ##STR120##
A 8.36 g. (20 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 25 ml. of freshly distilled anhydrous pyridine. The solution is treated dropwise with 4.08 g. (about 22 millimoles) of p-nitrobenzoyl chloride dissolved in 25 ml. of the freshly distilled anhydrous pyridine. The solution is allowed to stir overnight at room temperature. TLC in the morning shows only a small amount of starting material left. The reaction mixture is poured into 25 ml. of water and taken to dryness at 50° on the rotary evaporator. The residue is absorbed onto a 200 g. column of silica gel made up with cyclohexane, ethyl acetate, 95% ethanol and eluted with 20, 50 ml. fractions of the same solvent. Fractions 7-16 are combined after TLC's are run on the fractions, slurried in methanol, the crystalline solid filtered and washed with a small amount of methanol. Yield 4.0 g. This material is then dissolved in 100 ml. of methanol and treated with 4.0 g. of zinc dust at reflux for 15 minutes on the steam bath. No starting material is left at this point. The zinc is filtered off and the preparation taken to dryness. The solid is extracted with methanol and the extracts added to a 200 g. column of silica gel and eluted with 20, 50 ml. fractions of MEK, acetone, H 2 O (72:20:8). Fraction 14 contains a few mgs. of crystals which are recrystallized from acetone-H 2 O, m.p. 244°-245° dec. This material moves on TLC at about the same rate as the 5'-O-benzoyl CA, 3'-O-benzoyl and the 2'-O-benzoyl CA.
EXAMPLE 20 Preparation of 5'-O-2,4,6-triisopropylbenzenesulfonyl ara-cytidine ##STR121##
A 4.18 g. (10 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 50 ml. of freshly distilled anhydrous pyridine. The solution is treated dropwise with 4.54 g. (15 millimoles) of 2,4,6-triisopropylbenzenesulfonyl chloride dissolved in 10 ml. of pyridine. The reaction mixture is allowed to stir at room temperature over the weekend then poured into 60 ml. of water and taken to dryness at 50°. This crude gum is then dissolved in 50 ml. of methanol, 5 g. of zinc dust added and the reaction mixture heated to boiling for 1/2 hour on the steam bath. TLC shows no starting material left. The preparation is filtered free of zinc and taken to dryness on the rotary evaporator. The crude gum is then absorbed onto a 200 g. column of silica gel and eluted with 20, 100 ml. fractions of MEK, acetone and H 2 O. Fractions 7-20 all show one spot by TLC moving a little slower than the starting material and appearing to be the desired product. A 1 l. strip fraction of methanol is taken and also contains some material that was one spot moving with the fractions 7-10. Fractions 7-20 and the 1 l. methanol strip are combined, taken to dryness and crystallized once from methanol-water, then again from methanol. Yield 1.175 g., m.p. 188.5°-89.5° sl. dec. Another m.p. on the same sample does not melt until 228° and it dec. Recrystallized, from methanol a sample for analysis, m.p. 228° dec.
Anal. Calcd. for C 24 H 35 O 7 N 3 S: C, 56.56; H, 6.92; N, 8.25; S, 6.29. Found: C, 56.58; H, 6.94; N, 8.23; S, 6.08.
Ultraviolet Spectrum λ max EtOH (ε × 10 -3 )!: 228 (17.85); 274 (10.60); 283 sl sh (8.60).
Infrared Spectrum ν cm .spsb.-1 mull !: 3350, 3280, 3220, 3160 sh, 1665, 1640, 1615, 1575 sh, 1530, 1495, 1350, 1290, 1180, 1100, 1090, 1010, 980, 960 and 790.
NMR and the infrared spectrum are proper for the sulfonate.
EXAMPLE 21 Preparation of 5'-O-isobutyryl ara-cytidine ##STR122##
A 8.36 g. (20 millimoles) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 10 ml. of freshly distilled anhydrous pyridine. The solution is treated with 3.5 g. (about 22 millimoles) is isobutyric anhydride dropwise at room temperature with stirring. The reaction mixture is allowed to stir at room temperature overnight. A TLC is run on the crude reaction in the morning. 25 ml. of water is added to the preparation and the preparation is taken to dryness at 50°. The glassy residue is then absorbed onto a 200 g. column of silica gel and eluted with 10, 100 ml. fractions of cyclohexane, ethyl acetate, 95% EtOH (5:3:1). TLC's are run on the first of the fractions. Fractions 5 and 6 are combined on the basis of the TLC results and recystallized from methanol. Yield 2.0 g., m.p. 255° dec. One spot by TLC. This 2.0 g. of material is then dissolved in 50 ml. of methanol and treated with 2.0 g. of zinc dust at reflux for 10 minutes on the steam bath. TLC shows no starting material left. The zinc is filtered off and the methanol removed at 50° on the rotary evaporator. The clear glassy residue is then absorbed onto a 200 g. column of silica gel made up with cyclohexane, ethyl acetate, 95% EtOH (5:3:1). The column is eluted with 1 l. of the same solvent. Only a small amount of oil is eluted. The column is then eluted with 12, 100 ml. fractions of methyl ethyl ketone, acetone, H 2 O (72:20:8), TLC's are run on fractions 5 through 9. On the basis of the results fractions 7, 8 and 9 are combined and recrystallized from water. Yield, 990 mg., m.p. 179°-184°. Recrystallized from water once for analysis, a sample has m.p. 206°-208°. (Heating rate about 3° per minute. Melting point varies.) If put in bath at 180°, sample melts immediately. If heating rate was 15°-20° per minute, m.p. 212°-214°.
Anal. Calcd. for C 13 H 19 O 6 N 3 .1/2H 2 O: C, 48.44; H, 6.25; N, 13.04. Found: C, 48.62; H, 5.98; N, 13.33.
Ultraviolet Spectrum λ max EtOH (ε × 10 -3 )!: 233 sl sh (7.60); 273 (8.70).
Infrared Spectrum ν cm .spsb.-1 mull !: 3400, 3340, 328 sh, 3210, 3120 sh, 1740, 1715, 1655, 1640, 1625, 1535, 1490, 1285, 1205, 1165, 1110, 1095, 1050, 815, and 780.
EXAMPLE 22 Preparation of 5'-O-3,4,5-trimethoxybenzoyl ara-cytidine ##STR123##
A 8.36 gram (20 millimole) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 100 ml. of freshly distilled anhydrous pyridine. The solution is treated with stirring and at room temperature with 4.85 g. (about 22 millimole) of 3,4,5-trimethoxybenzoyl chloride. Reaction is allowed to stir overnight at room temperature. A TLC was run in the morning, in the system silica gel, cyclohexane, ethyl acetate, 95% EtOH. The solution still shows starting material left. The reaction mixture is heated to 50° in an oil bath overnight. TLC plate shows no starting material in the crude mixture. Compound streaks and is hard to recognize. A white solid that precipitates out of the solution is spotted also. This material does not move from the origin. The reaction mixture is poured into 60 ml. of water and taken to dryness on the rotary evaporator. The gum is absorbed onto a 200 g. column of silica gel and eluted with 15, 100 ml. fractions of cyclohexane, ethyl acetate, 95% EtOH. Column is made up with this solvent also. On the basis of TLC results, fractions 4-9 are combined in methylene chloride, washed once with saturated bicarbonate one with water, dried through sodium sulfate and taken to dryness. This removes all the slower moving material which is the trimethoxy benzoyl acid by TLC. The residue is dissolved in 100 ml. methanol and 3 g. zinc dust were added. This mixture was heated at the reflux temperature for 10-15 mins. and then cooled. The cooled solution was filtered to remove zinc dust, and the methanol was removed by evaporation at 50° C. The residue thus obtained (8.17 g.) was dissolved in methylene chloride and absorbed onto a 200 g. column of silica gel made up with MEK, acetone, H 2 O (72:20:8) and eluted with 12, 100 ml. fractions of the same solvent. Fractions 6, 7, 8 and 9 are spotted on a TLC plate and run in the same solvent. Based on the TLC results fractions 7, 8 and 9 are combined and recrystallized from methanol. Yield 2.410 g., m.p. 143°-145°. Recrystallized from methanol, a sample for analysis shows, m.p. 137°-139°.
Anal. Calcd. for C 19 H 23 O 9 N 3 .l H 2 O: C, 50.11; H, 5.53; N, 9.23. Found: C, 50.50; H, 5.41; N, 9.15.
Ultraviolet Spectrum λ max EtOH (ε × 10 -3 )!: 214 (40.30); 269 (17.75); 305 sl sh (2.55).
Infrared Spectrum ν cm .spsb.-1 mull !: 3420, 3320, 3260, 3220, 1715, 1645, 1600, 1520, 1500, 1340, 1280, 1225, 1125, 1095, 1075, 1065, 1030, 995, 860, and 805.
Both ultraviolet spectrum and infrared spectrum are proper for the proposed structure.
EXAMPLE 23 Preparation of 5'-O-2,6-dimethylbenzoyl ara-cytidine ##STR124##
A 8.36 g. (20 millimole) sample of N 4 -trichloroethoxycarbonyl ara-cytidine is dissolved in 100 ml. of freshly distilled anhydrous pyridine. The solution is treated at room temperature with 3.70 g. (about 22 millimole) of 2,6-dimethylbenzoic chloride. The reaction mixture is stirred overnight. The chloride is dissolved in 10 ml. of CH 2 Cl 2 and added dropwise. TLC in the morning shows some starting material left. Another 3.70 g. in 10 ml. of CH 2 Cl 2 is added dropwise and the preparation allowed to go overnight at room temperature. In the morning TLC shows almost no starting material left. 50 ml. of water are added and the preparation taken to dryness at 50° on a rotary evaporator. The residue is dissolved in 200 ml. of CH 2 Cl 2 and extracted twice with 100 ml. each of saturated bicarbonate. The CH 2 Cl 2 solution is washed once with 200 ml. of H 2 O and dried through sodium sulfate, then taken to dryness. The gum is then absorbed onto a 200 g. column of silica gel made up with cyclohexane, ethyl acetate, 95% EtOH. The column is eluted with 20, 100 ml. fractions of the same solvent. TLC's are run on fractions 7-15. Based on the TLC results, fractions 7-12 are combined and recrystallized from methanol. Yield 3.0 g. This material has one spot by TLC and moves the same on the plate as 2,4,6-trimethylbenzoyl N 4 -trichloroethoxycarbonyl ara-cytidine. This 3 g. of material is dissolved in 100 ml. of methanol, 3 g. of zinc dust added and the preparation heated to reflux for 15 minutes on the steam bath. At this time TLC shows no starting material left. The zinc is filtered off and the methanol removed in the evaporator. The clear glassy residue is then absorbed onto a 200 g. column of silica gel made up with MEK, acetone, H 2 O (72:20:8) and eluted with 10, 100 ml. fractions of the same solvent. TLC's are run on fractions 3, 4, 5 and 7. Fractions 4-9 are combined and recrystallized from methanol. The yield is 1.24 g. m.p. 238°-240° dec. A sample is recrystallized once from methanol for analysis, m.p. 238°-240° dec.
Anal. Calcd. for C 18 H 21 O 6 N 3 .1/2H 2 O: C, 56.24; H, 5.77; N, 10.93. Found: C, 56.31; H, 6.03; N, 11.17.
Ultraviolet Spectrum λ max EtOH (ε × 10 -3 )!: 233 sl sh (10.25); 273 (9.55).
Infrared Spectrum ν cm .spsb.-1 mull !: 3500 sh, 3400, 3340, 3280 w, 3220, 1740 sh, 1715, 1655, 1635, 1615, 1530, 1485, 1785, 1270, 1245, 1110, 1095, 1070, 1050, 815 and 710.
EXAMPLE 24 Preparation of 5'-O-palmityl ara-cytidine
Ara-cytidine hydrochloride (2.80 g., 0.01 mole) is dissolved in 25 ml. dimethylformamide and 3.05 g. (0.011 mole) of palmityl chloride is added. The solution is allowed to stand at room temperature for 7 hours. The solvent is evaporated in vacuo (oil pump) and the resultant oil is stirred with 70 ml. of 0.3N sodium bicarbonate. The resultant solid is collected on a filter, washed several times with water, pressed dry, and then washed three times with 25 ml. ethyl acetate and air dried. Yield, 2.52 g. (52%), m.p. 135°-145°. Thin layer chromatography showed a single ultraviolet-absorbing spot in several solvent systems. A sample is recrystallized once from methanol (82% recovery) for analysis, m.p. 145°-148°.
Anal. Calcd. for C 25 H 43 N 3 O 6 : C, 62.34; H, 9.00; N, 8.72. Found: C, 62.65; N, 9.29; N, 8.75.
Infrared and ultraviolet absorption curves are identical to that of an authentic sample, and the material is chromatographically identical to the authentic sample in several solvent systems.
EXAMPLE 25 Preparation of 5'-pivaloyl ara-cytidine
Ara-cytidine hydrochloride (3.5 g., 0.01 mole on the basis of 20.5% solvent of crystallization), is suspended in 25 ml. of dimethylacetamide and 1.3 g. (10% excess) of pivaloyl chloride is added. The mixture is stirred at room temperature. As the material reacts is slowly dissolves. After stirring overnight, the mixture is clear. The solution is concentrated to a low-volume in vacuo (oil pump) and the residual oil is stirred with 100 ml. ethyl acetate-ether (1:1). This treatment is repeated twice more, decanting and centrifuging. The semi-solid is then triturated with 20 ml. of N NaHCO 3 , filtered, and washed several times on the filter with water. The white crystalline solid is dried in an air stream. Yield 2.24 g. (66%), m.p. 252°14 258° dec. TLC (EtOAC-DMF-H 2 O, 75:15:5) shows that the material consist of a single spot*, Rf = 0.38. About 1 g. of this material is recrystallized from 15 ml. methanol. Recovery 0.4 g., m.p. 261°-262° dec. The remainder of the material (1.24 g.) is stirred with hot butanol. It changes crystalline form and becomes sparingly soluble in the butanol. A total of 25 ml. of hot butanol is used, but much remains insoluble. Recovery 1.04 g., m.p. 259°-260° dec. The mother liquors are combined, evaporated to dryness, and the residue is recrystallized from methanol. Recovery 0.36 g., m.p. 254°-256° dec.
EXAMPLE 26 Preparation of 5'-octanoyl ara-cytidine
Ara-cytidine hydrochloride (5.6 g., 0.02 mole) is dissolved in 50 ml. dimethylformamide and 3.6 g. (0.022 mole) of octanoyl chloride is added. The clear solution is allowed to stand over the weekend.
TLC shows that a good yield of the product (Rf = 0.38, run with an authentic sample as standard) is obtained, with a trace of a component of Rf = 0.95, small amounts of other products of Rf's = 0.70, 0.52, 0.24, and material of low Rf trailing to the origin. The solvent is evaporated with vacuum and the oil is stirred with about 100 ml. ether three times. The semi-solid is then thoroughly stirred with 40 ml. N NaHCO 3 , the resultant solid is collected and washed with H 2 O until neutral. The solid is air-dried. Weight 4.89 g. TLC (as above) shows that the product at this stage has a small amount of materials of Rf's = 0.70 and 0.52 and a trace of material trailing behind the product. The product is crystallized from 60 ml. hot ethyl acetate as needles. Recovery 4.07 g. (55%), m.p. 158°-161°.
EXAMPLE 27 Preparation of 5'-cyclohexylcarbonyl ara-cytidine
Ara-cytidine hydrochloride (20% by weight of solvent; 17.5 g., 0.05 mole) is dissolved in 125 ml. dimethylformamide and 8.06 g. (10% excess) of cyclohexanecarboxylic acid chloride is added. The clear solution is allowed to stand at room temperature overnight.
The solvent is evaporated in vacuo and the oil is stirred several times with ether. The oil is then thoroughly triturated with 100 ml. N sodium bicarbonate. The solid is filtered, washed with water and air dried. The material is crystallized from 100 ml. ethyl acetate. The material dissolves readily in warm ethyl acetate and then crystallizes out in a form that will not redissolve in this solvent. The crystalline material is collected, washed with ethyl acetate, ether and dried. Weight 5.58 g., m.p. 232° dec. The mother liquor is evaporated to dryness and the crystalline residue is triturated with hot ethyl acetate, cooled and collected as above. Weight 3.86 g., m.p. 227°-229° dec. Total yield 9.44 g. (53%). The Rf is identical to that of an authentic sample.
EXAMPLE 28 Preparation of 5'-acetyl-ara-cytidine
Ara-cytidine hydrochloride dimethylformamide solvate (17.5 g., 0.05 mole) is dissolved in 125 ml. dimethylformamide and 4.32 g. (10% excess) of acetyl chloride is added. The clear solution is allowed to stand overnight at room temperature.
The solvent is evaporated in vacuo, and the resultant oil is stirred several times with ether. The residual oil is dissolved in water, the pH is adjusted to 1.5, and the solution is extracted three times with equal volumes of ethyl acetate. The pH of the aqueous solution is adjusted to 7, and the solvent is evaporated in vacuo. The residual oil is dissolved in ethanol and sodium chloride is removed by filtration. The solvent is evaporated in vacuo to leave an oil weighing 16.5 g.
About 13 g. of this product is purified by chromatography over silica gel (Merck-Darmstadt, 0.05-0.2 mm) using the solvent system methylethylketone-acetone-water (72:20:8). About 800 g. of adsorbent for a column 56 mm in diameter is used. The material is dissolved in a small volume of water for adsorption on the column, and then elution with the solvent is begun. The volume of each fraction is 100 ml., and the elution of the material is followed by TLC. The 5'-acetyl ara-cytidine is eluted in fractions 33-51, which is combined and evaporated in vacuo to leave a crystalline residue weighing 7.0 g. The product is recrystallized from 60 ml. 1-butanol, recovery 4.05 g., m.p. 184°-185°. TLC in several solvent systems shows that the material is chromatographically identical to an authentic sample of 5'-acetyl ara-cytidine. A small amount of additional product is recovered from the mother liquor above to give a total yield of purified product of 38%.
EXAMPLE 29 Preparation of 5'-adamantoyl ara-cytidine
Ara-cytidine hydrochloride (63 g., 0.225 mole) is suspended in 1100 ml. of dimethylacetamide. About 51 g. (10% excess) of 1-adamantanecarboxylic acid chloride is added and the mixture is stirred overnight at room temperature. The mixture is filtered to remove about 4.8 g. of solid. TLC of the filtrate shows a considerable amount of unreacted cytosine arabinoside. An additional 32 g. (0.16 mole) of 1-adamantanecarboxylic acid chloride is added and the reaction is allowed to proceed for an additional 24 hours. The solution is concentrated in vacuo to a low volume and the oil is triturated three times with 500 ml. of ethyl acetate-ether (1:1). The oil is thoroughly triturated with 650 ml. N NaHCO 3 , the resultant crystalline solid is collected by filtration and washed several times with water. The filter cake is pressed dry and the solid is washed twice with ethyl acetate and then with ether, and dried. Yield, 63 g. (69%), m.p. 282° dec. Recrystallization from 400 ml. dimethylacetamide-1600 ml. ethyl acetate gives 61.1 g., m.p. 291° dec. TLC in several solvent systems, and comparative melting point determinations show that the product is identical to an authentic sample of 5'-adamantoyl ara-cytidine.
EXAMPLE 30 Preparation of 5'-O-L-trans-3- n-propyl!-hygric acid ester of ara-cytidine
L-trans-3- n-propyl!-hygric acid hydrochloride is heated to reflux in excess thionyl chloride until the acid is completely dissolved. The excess thionyl chloride is then removed by distillation under reduced pressure. The residue is taken to dryness three times with 5 volumes of dry benzene. The residue is then dissolved in a minimum amount of dry dimethylacetamide and added to a solution of ara-cytidine hydrochloride in the same solvent and stirred at room temperature overnight. The 5'-ester is then isolated as described in Example 22.
EXAMPLE 31 Preparation of 5'-lauroyl-ara-cytidine
Ara-cytidine hydrochloride (5.0 g., 0.018 mole) is dissolved in 45 ml. dimethylformamide and 4.33 g. (0.02 mole) of lauroyl chloride is added dropwise. The reaction mixture is stirred overnight at room temperature. The solvent is evaporated at reduced pressure and the resulting gum triturated with 1N sodium bicarbonate. The resulting precipitate is filtered and dissolved in a minimum volume of acetone and the solution filtered. The solution is allowed to cool to room temperature and the product crystallizes. After all apparent crystallization has occurred, it is stored in the freezer overnight. Filtration provides 4.6 g (60%) of a white solid, m.p. 153°-155° C. TLC (MEK*: acetone:H 2 O, 60:20:15) shows one zone, Rf=0.57.
EXAMPLE 32 Preparation of 5'-O-lauroyl-ara-cytidine hydrochloride
Following the procedure of Example 7, 5'-O-lauroyl-ara-cytidine hydrochloride is prepared by substituting 5'-O-lauroyl-ara-cytidine for 5'-palmityl cytosine arabinoside.
EXAMPLE 33 Tablets for Oral Administration
1000 Scored tablets for oral use, each containing 500 gm. of 5'-O-palmityl ara-cytidine, are prepred from the following types and amounts of ingredients:
5'-O-palmityl ara-cytidine -- 500 gm.
Starch, U.S.P. -- 35 gm.
Talc, U.S.P. -- 25 gm.
Calcium stearate -- 3.5 gm.
The powdered 5'-O-palmityl ara-cytidine is granulated with a 4% w./v. aqueous solution of methylcellulose U.S.P. To the dried granules is added a mixture of the remainder of the ingredients and the final mixture is compressed into tablets of proper weight.
Satisfactory clinical response is obtained in adults with acute leukemia with 1 tablet 3 times a day.
Using the procedure above, tablets are similarly prepared containing 5'-O-palmityl ara-cytidine in 3 mg. and 1000 mg. amounts by substituting 3 gm. and 1000 gm. of 5'-O-palmityl ara-cytidine for the 500 gm. used above.
EXAMPLE 34 Injectable Dispersion
A sterile aqueous dispersion suitable for intramuscular use, and containing 250 mg. of 5'-O-palmityl ara-cytidine hydrochloride in each ml., is prepared from the following ingredients:
______________________________________5'-O-palmityl ara-cytidinehydrochloride 250 gm.Water for injection, q.s. 1,000 gm.______________________________________
A daily dose of 1 ml. provides a satisfactory clinical response.
EXAMPLE 35 Injectable Preparation
A sterile aqueous preparation suitable for intramuscular injection and containing 10 mg. of 5'-O-palmityl ara-cytidine in each 2 ml. is prepared from the following ingredients:
______________________________________5'-O-palmityl ara-cytidine 5 gm.Polyethylene glycol, 4000 U.S.P. 30 gm.Sodium chloride, U.S.P. 9 gm.Preservative, q.s.Water for injection, q.s. 1,000 ml.______________________________________
EXAMPLE 36 Injectable Preparation
A sterile preparation suitable for intramuscular injection and containing in each milliliter 100 mg. of 5'-O-palmityl ara-cytidine is prepared from the following types and amounts of materials:
______________________________________5'-O-palmityl ara-cytidine 100 gm.Aluminum monostearate-peanutoil gel, q.s. to 1,000 gm.______________________________________
A mixture of 2 parts aluminum monostearate and 98 parts of peanut oil is slowly heated with stirring to a temperature of 100° C. The temperature is maintained at this level for 1 hour when gelling is complete and is then raised to 150° C. and maintained at this temperature for 1 hour. The gel is then cooled and 100 grams of sterile, powdered 5'-O-palmityl ara-cytidine is incorporated aseptically with stirring and the total volume made up to 1000 ml. with additional gel and further stirring.
EXAMPLE 37 Sterile Powder for Reconstitution
Sterile vials each containing 50 mg. of 5'-O-palmityl ara-cytidine hydrochloride are prepared by first sterilizing 50 gm. of the 5'-O-palmityl ara-cytidine by treatment with ethylene oxide and thereafter filling 50 mg. into each of 1000 sterile vials. At the time of use, the contents of a vial are reconstituted with q.s. water for injection to provide a sterile preparation for injection administration.
EXAMPLE 38 Sterile Preparation
24,000 Ml. of sterile preparation are prepared as follows:
______________________________________Each mil: Total______________________________________57.5 mg. 5'-O-palmityl ara-cytidine hydrochloride 1380 gm.5 mg. sodium citrate 120 gm.9.45 mg. benzyl alcohol 227 gm.2.3 mg. sodium bisulfite 55.2 gm.Sodium hydroxide (50% aqueoussolution), q.s.Water for injection, q.s. ad 24,000 ml.______________________________________
Directions: Dissolve the 5'-O-palmityl ara-cytidine hydrochloride, sodium citrate and benzyl alcohol in 2,000 ml. water. Add the sodium bisulfite and adjust the pH 7.0 with the alkali.
EXAMPLE 39
Following the procedure of the preceding Examples 33, 35, and 36, compositions are prepared substituting equivalent amounts of the pharmaceutically acceptable acid addition salts of 5'-O-palmityl ara-cytidine for the free base of the examples.
EXAMPLE 40
Following the procedure of the preceding Examples 34, 37, and 38, compositions are prepared substituting equivalent amounts of the free base of 5'-O-palmityl ara-cytidine hydrochloride for the pharmaceutically acceptable acid addition salt of the examples.
EXAMPLE 41
Following the procedure of the preceding Examples 33, 35, and 36, compositions are prepared substituting equivalent amounts of the other ester compounds of the subject invention or the pharmaceutically acceptable acid addition salts of each for 5'-O-palmityl ara-cytidine to provide similar therapeutic properties.
EXAMPLE 42
Following the procedure of the preceding Examples 34, 37, and 38, compositions are prepared substituting equivalent amounts of the free base of the other ester compounds of the subject invention or the pharmaceutically acceptable acid addition salts of each for 5'-O-palmityl ara-cytidine hydrochloride to provide similar therapeutic properties.
EXAMPLE 43 Preparation of 5'-O-(p-anisoyl) ara-cytidine hydrochloride
Following the procedure of Example 7, 5'-O-(p-anisoyl) ara-cytidine hydrochloride is prepared by substituting 5'-O-(p-anisoyl) ara-cytidine for 5'-palmityl cytosine arabinoside.
As locally administered (intraarticular) immunosuppressive agents certain compounds of the subject invention, including 5'-O-benzoyl-ara-cytidine, 5'-O-p-anisoyl-ara-cytidine, 5'-O-palmityl-ara-cytidine and 5'-O-lauroyl-ara-cytidine have been conceived as useful for clinical application in rheumatoid arthritis as disclosed in U.S. patent application Ser. No. 671,289, filed Mar. 29, 1976. The article by W. J. Wechter et al., ara-Cytidine Acylates. Use of Drug Design Predicators in Structure-Activity Relationship Correlation, J. Med. Chem., 18, 339 (1975) deals with the development of a depot form of the nucleoside ara-cytidine employing in vitro correlates for the design of a drug for clinical application in cancer and rheumatoid arthritis, the latter to be effective as a locally administered (intraarticular) immunosuppressive agent.
Certain compounds of the subject invention, particularly 5'-O-benzoyl-ara-cytidine, 5'-O-lauroyl-ara-cytidine, 5'-O-p-anisoyl-ara-cytidine, and 5'-O-palmityl-ara-cytidine, have shown in mice an unexpected and significant increase in anti-L1210 leukemia activity (percent increase in life span) upon single dose administration of about 200 mg./kg. of compound one day after the injection of L1210 cells as can be seen in Table 1 of the article W. J. Wechter et al. ara-Cytidine Acylates. Use of Drug Design Predictors in Structure-Activity Relationship Correlation, J. Med. Chem. 18, 339-340 (1975). As noted in the article appearing in J. Med. Chem., 18, 339 (1975), much of the percent ILS data was previously published, see for example G. D. Gray et al., Immunosuppressive, Antiviral and Antitumor Activities of Cytaratine Derivatives, Biochem. Pharm., 21, 465 (1972).
In a pilot pharmacology study, clinical phase 1 trials of 5'-O-palmityl-ara-cytidine were concomitantly carried out at the M. D. Anderson Hospital. Cancer Research 37, 1640 (June 1977), eleven patients with metastasized solid tumors were treated with single 1m injections at an initial dose of 225 mg./sq m. Doses were increased by 20 percent increments every 21 days, up to a maximum dose of 1500 mg./sq m. Among the 11 patients, 2 each received 1, 2, 3, 4 or courses and 1 had 8 courses. No patient showed any toxic effect or myelosuppression. Although no myelosuppression with 5'-O-palmityl ara-cytidine was noted in the limited clinical phase 1 trials reported in Cancer Research, 37 1640 (June 1977), these results are not believed conclusive in determining the efficacy of the compound in the treatment of acute leukemia upon multiple site injections and/or daily administration.
In the same pharmacology study described above, the rate of absorption (estimated by excretion rate) of 5'-O-benzoyl ara-cytidine in one patient was studied and was not superior to that observed with 5'-O-palmityl-ara-cytidine and clinical trials were not attempted. | 5'-Esters of ara-cytidine (1-β-D-arabinofuranosylcytosine) are prepared by reacting ara-cytidine with β,β,β-trihaloethoxycarbonyl halide or other protective agency to form a protective amido group on the primary amino nitrogen of ara-cytidine and then reacting the thus-protected compound with a reagent reactive with the 5'-O-hydroxyl group, e.g., an acylating agent, to form the 5'-O-derivative. The β,β,β-trihaloethoxycarbonyl or other protective group is then removed. Alternately, the primary amino group of ara-cytidine can be protected from acylation by protonation. The 5'-O-derivatives in their free base or salt form are characterized in that they display the property of sustained release of the compound, ara-cytidine, when administered intramuscularly or subcutaneously. Ara-cytidine is known for its anti-viral action and for its usefulness as an agent for controlling leukemias, including acute leukemia, and the sustained release property extends the usefulness of ara-cytidine for these purposes and as an immunosuppressive agent. The 5'-O-derivatives of this invention can also be administered orally. | 8 |
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